Arkansas Native Plant Month 2018

April is Arkansas Native Plant Month! To celebrate, we have teamed up with our partners at the Arkansas Natural Heritage Commission, Audubon Arkansas, Botanical Garden of the Ozarks, Hobbs State Park, Northwest Arkansas Land Trust, Northwest Arkansas Master Naturalists, and the U.S. Forest Service to bring you a month of nature walks, educational events and talks, and native plant sales throughout the state. We hope to see you at one of these events in April!

April 1, 9:30 am – Warren Prairie Natural Area

Join Eric Hunt to tour one of the largest prairie preserves in Arkansas. Warren Prairie Natural Area, located in the Coastal Plain, consists of a mosaic of salt slicks, saline barrens, Delta post oak flatwoods, mound woodlands, pine flatwoods and woodlands, and bottomland hardwood forest communities. Soils at the site containing naturally high amounts of sodium and magnesium salts account for the sparse and irregular distribution of trees and the resultant dominance of grasses and other herbaceous vegetation in the barrens and associated woodlands. Stands of dwarf palmetto are distributed irregularly and lend a tropical aspect to the area. The natural area provides critical habitat for the state’s largest population of the federally threatened plant, geocarpon (Geocarpon minimum).

Directions: From Warren, take U.S. Highway 278 East approximately 4.5 miles, across the Saline River, to the junction of State Highway 172. Turn right (south) and proceed 2.0 miles to parking lot and sign on left (east). We will follow a 2.2-mile loop trail. Waterproof boots are strongly recommended, as this is a seasonally wet prairie. Bring insect repellant, snacks, lunch and water. For questions and to reserve a spot, contact Eric Hunt at 415-225-6561 or

April 4, 6:00 pm: Wednesdays on the Greenway with Bob Morgan

Meet at Gordon Long Park, located at 2800 N Gregg Ave, Fayetteville. Wednesdays on the Greenway provide an opportunity to view native plants in the urban setting. This year we are utilizing auxiliary trails that connect to the Greenway. Walks start at 6:00 pm and last till we get tired of looking. RSVP is not required, but you can contact Bob at or 479-422-5594 with questions.

April 7: Visit our Farmers Market Tables!

Visit us at the market! We’ll have printed information available about native plants, invasive plants, native plant gardening, and a list of native plant nurseries. We’ll also be selling t-shirts and hats that support ANPS programs. Come see us at these locations:

  • Hot Springs Downtown Farmers Market, 9-12
  • Hillcrest Farmers Market, Little Rock, 8-12

April 13-15: ANPS Spring Meeting, Russellville

A weekend of wildflower walks, presentations and good company with fellow native plant enthusiasts! Everybody is welcome to attend! Meeting registration is only $10 with no pre-registration required. Registration will begin at 5:00 pm on Friday, April 13. Full information is available here.

April 14, 10:00 am: Botanical Garden of the Ozarks, Fayetteville

Tour the native plant gardens with Lissa Morrison who will talk about using native species successfully in the residential landscape. The cut-off number is 20. If you are not a member of the Botanical Garden of the Ozarks, there is a $7 charge for this trip. If you have volunteered with Master Naturalists or OCANPS in past events for BGO, you will not be required to pay. RSVP to to hold your spot.

April 17, 1:00 – 5:00 pm: BIOBLITZ – Little Rock’s Fourche Creek Bottoms at Interstate Park

Join Eric Hunt and Eric Sundell for a leisurely walk and exciting bioblitz, co-sponsored by Audubon Arkansas and ANPS, to Fourche Creek bottoms in Little Rock.

Directions: We’ll leave from the pavilion at Interstate Park (entrance on Arch Street, about 3/4 mile south of Roosevelt Road and just north of I-30), pass through the fields to a riparian forest leading down to a lovely cypress swamp at the creek. For better directions, call Eric Sundell at 870-723-1089.

April 18, 6:00 pm: Wednesdays on the Greenway with Bob Morgan

Tour the Town Branch Trail at Razorback Road with Bob Morgan. Wednesdays on the Greenway provide an opportunity to view native plants in the urban setting. This year we are utilizing auxiliary trails that connect to the Greenway. Hikes start at 6:00 pm and last till we get tired of looking.

Directions: From W. 15th Street, turn south onto S. Razorback Trail which the trail crosses at the bridge, where we can park. RSVP is not required, but you can contact Bob at or 479-422-5594  with questions.

April 21, 9:00 am – 4:00 pm: 2018 Native Plant Market at the Little Rock Audubon Center                                   

Buy locally-grown plants from Arkansas’ best native plant nurseries, and then plant a pollinator garden at your local school or neighborhood park!  ANPS will have a table with information and merchandise at this event. Full information is available here.

April 21, 10:00 am: Native Plant and Wildflower Walk at Hobbs State Park near Rogers

Join Master Naturalist Joan Reynolds as she leads a native plant and wildflower walk on two short trails at Van Winkle Hollow. Both trails have many interesting plants. We will start out on the Sinking Stream Trail at Van Winkle, a ½ mile unpaved loop trail along Little Clifty Stream full of wildflowers and other native plants. Then we will walk the Historic Trail at Van Winkle which is a ½ mile paved/gravel trail with its own interesting flora. Both trails are mostly level with some slopes so it will be a leisurely walk.

Directions: From Rogers, take Hwy 12 east approximately 12 miles to the Van Winkle Historic Trailhead parking area. We will meet in the parking area at 10:00 am. Van Winkle Hollow is about 1.5 miles West of Hobbs State Park Visitor Center. RSVP is not required, but you can contact the Hobbs State Park Visitor Center at 479-789-5000 if you have questions or need directions.

April 21, 12:00 pm: Wildflower and Insect Walk on Kessler Mountain, Fayetteville

Join entomologist Sim Barrow of the Northwest Arkansas Land Trust and Jennifer Ogle of ANPS at the Kessler Mountain Outdoor Classroom and Nature Center, located at 1725 Smokehouse Trail in Fayetteville, to discover the plants and insects that live in the nature center’s gardens and surrounding forest. We will tour the gardens to learn some of the Ozark native plants that may grow well at your own home and learn how to support important native insects such as solitary bees and monarch butterflies! See firsthand the transformation of the woods around the Smokehouse now that invasive bush honeysuckle plants have been removed from the forest understory!

Directions: From I-49 in Fayetteville, take M.L.K. Jr. Blvd west approximately 1.5 miles to Smoke House Trail/Rupple Road and turn left. Park in the Old Smokehouse parking lot on the north side of the building. Contact Jennifer Ogle at with questions. RSVP is not required.

April 22, 10:00 am: Rich Mountain/Queen Wilhelmina State Park

Join Eric Hunt for an exploration of Rich Mountain in the Ouachitas of western Arkansas. One of the highest east-west ridges in the Ouachita Mountains, it contains a diverse flora. Due to the elevation, the bloom time here is a few weeks later than at lower elevations, so we hope to see the last of the spring ephemerals. Meet at the parking area of Spring Trail. As time permits we will explore the Spring Trail, the Ouachita National Trail starting at the Pioneer Cemetery. Wear sturdy shoes, bring insect repellant, snacks, lunch and water.

Directions: from Mena, take Arkansas 88 north for approximately 12.5 miles. The Spring Trail Parking area is on your right directly off AR 88. For questions and to reserve a spot, contact Eric Hunt at 415-225-6561 or

April 27-28: Northwest Arkansas Master Naturalists Native Plant Sale at Botanical Garden of the Ozarks, Fayetteville                       

Support the Northwest Arkansas Master Naturalists native plant program by purchasing native trees, shrubs, and perennials they have grown from seed and seedlings. The event is open to BGO members only on Friday, April 27, 5:00-8:00 pm, and to the public on Saturday, April 28, 8:00 am-12:00 pm. Full information is available here.

April 28, 9:30 am: Arkansas Valley Prairie Tour – Cherokee Prairie and H.E. Flanagan Prairie

Join ANHC botanist Brent Baker to explore a couple of natural areas in the Arkansas Valley Ecoregion. We’ll start off with a tour at Cherokee Prairie Natural Area and then caravan over to the nearby H.E. Flanagan Prairie Natural Area. These natural areas preserve some of the largest tracts (nearly 600 and 350 acres, respectively) of remnant tallgrass prairie habitat once abundant (covering about 135,000 acres) in the western Arkansas Valley Ecoregion. The soils in these prairies are derived from weathered shale, differing from prairies elsewhere in Arkansas. We’ll see a number of spring wildflowers and we’ll try to find the rare Oklahoma grass-pink orchid (Calopogon oklahomensis), a high-quality tallgrass prairie obligate, which may be starting to flower around that time. Wear sturdy shoes, and bring insect repellant and sunscreen, snacks, lunch and water.

Directions: from AR Hwy 22 in Charleston, take AR Hwy 217 north approximately 2.6 miles to junction with AR Hwy 60. Turn left onto AR Hwy 60 and travel about 0.5 mile to pull-off parking areas on both north and south side of highway (you can also pull off to the side of the highway if parking areas are full but be sure to get far enough off the road to not hinder traffic). For questions and to sign up (so you can be contacted in case of cancellation), contact Brent Baker at or 479-970-9143.

April 28, 9:30 am: Grand Prairie Tour – Railroad Prairie, Downs Prairie, Konecny Prairie

Join Eric Hunt to explore several natural areas in the Grand Prairie of Arkansas. Railroad Prairie Natural Area occupies portions of the abandoned right-of-way of the former Chicago, Rock Island, and Pacific railroad along U.S. Highway 70 between Carlisle and DeValls Bluff. See prairie, herbaceous wetland, oak woodland and forest. A large portion of Railroad Prairie consists of tallgrass prairie, a habitat that was once much more common across the Grand Prairie of eastern Arkansas (Mississippi Alluvial Plain). Today, less than 1 percent of the prairies that occurred across this region remain. Explore the eastern end of Railroad Prairie and adjacent Downs Prairie as well as Konecny Prairie, just north of Stuttgart. We hope to see Oklahoma grass-pink orchid (Calopogon oklahomensis) at Downs Prairie. Wear sturdy shoes, bring insect repellant, snacks, lunch and water.

Directions: from Hazen, take US 70 east approximately 5 miles to Lawman Road/CR 24. Turn left onto Lawman road and park along the dirt road that curves to the right. For questions and to reserve a spot, contact Eric Hunt at 415-225-6561 or


Posted in Know Your Natives

Know Your Natives – Green Trillium

Green trillium (Trillium viridescens), of the Trillium (Trilliaceae) family is a spring ephemeral. It has a limited distribution in the U.S., occurring along eastern borders of Texas and Oklahoma, in southeastern Kansas and southwestern Missouri, and throughout western Arkansas. In Arkansas, it occurs primarily in the mountainous areas of the Ozark Plateaus, Arkansas Valley and Ouachita Mountains. Other common names include taper-tip trillium and Ozark trillium based on its primary occurrence in the Ozark Plateaus (not to be confused with Trillium ozarkanum). Preferred habitat is mesic, deciduous woodlands in rich, deep soils found on slopes and floodplains.

Green trillium, a rhizomatous perennial herb, produces straight, erect stalks with three leaves and often a single flower each. The segmented, shallow, horizontal rhizomes are round to somewhat flattened in cross-section with long slender roots. Equally spaced growth rings, wrapping around the rhizomes’s circumference, are prominent. New rhizomes develop over winter at the sides of older rhizomes and terminate with vertically rising shoots that produce vegetative growth. Over time, a thick root-mat with many stalks may form.

Green Trillium - Trillium viridescensPhoto 1: New stalks grow upright from tips of new horizontal rhizomes. Photo in early February

New stalks make their first appearance about mid-February as green tips rising above the duff, while white protective sheaths remain unseen. The green tips, at first tightly wound and vertically positioned, loosen as the stalks push above the ground surface. Stalks mature before heavy shading envelopes their habitat.

A mature stalk consists of a stem topped by three (occasionally more) large, whorled, sessile leaves and may or may not bear a single, sessile flower. The flower has three sepals and three petals. Stems are round in cross-section, slender, glabrous and without nodes. A stem may be two or more feet tall. (Occasionally, a stem may have four leaves along with four sepals and petals.)

The leaves are ovate-triangular to elliptical, glabrous, widest at the middle, with a tapered to rounded sessile base and a rounded to acuminate apex. The margins are smooth. Leaf size is rather variable, with the largest, subtending the flowers, up to 5 inches long and 3 inches wide. They are an overall medium green with an upper surface that may be lightly to heavily mottled with irregularly shaped and arranged dark green to silvery green splotches that are somewhat matched across the midrib. Lower sides of leaves are about the same color, except mottling is less noticeable. Mottling becomes less distinct as the growing season progresses. Leaves have a primary central vein (midrib) with an opposing pair or several pairs (depending on size) of arcuate secondary veins extending from base to tip. Tertiary veins branch off the primary vein and secondary veins toward leaf margins so that a triangular to rectangular pattern is created.

Green Trillium - Trillium viridescensPhoto 2: Mottling of leaves is strongest when they first expand. In this early March photo, sepals still cover the upright flower buds.

Flowers are at anthesis generally in early April. The three lanceolate, widely spreading sepals have a mostly uniform width, an acute to rounded tip and a slightly tapered sessile base. The three erect petals are somewhat twisted, with a broadened upper half that tapers to an acute tip and a narrowing lower half with a clawed base. Sepals are a medium green with possible slight purple coloration at their base, while petals are yellow green overall with variable purple coloration, mainly along their tapering lower half. Sepals may be over 2 inches long and 3/8 inch wide, while petals may be over 3 inches long and 3/8 inch wide. Margins of sepals and petals are entire. Venation of sepals and petals aligns with margins.

Green Trillium - Trillium viridescensPhoto 3: At anthesis, sepals flare horizontally while petals remain mostly upright. Photo taken mid-March.

Flowers have six strap-like, purplish brown, vertical stamens that consist of long, thin, strap-like and curved anthers atop short filaments (filaments may be absent). The inch-long anthers are positioned with concave sides toward the flower center. Stamens are somewhat twisted with their rounded apexes converging above the pistil. The dark colored anthers have light colored edges which dehisce (split) along their entirety to release pollen. The pistil terminates in three stout, purplish styles spreading apically into thick “wings”, with the stigmatic areas along the inner sides. The ovary is small and whitish. A pungent odor from the flower attracts pollinator instects.

Green Trillium - Trillium viridescensPhoto 4: Display shows one of three leaves (upper center), three sepals (right), three petals (left), six stamens (lower left and right) and the pistil (lower center). Note venation of leaf, sepals and petals.

With fertilization, the styles dry and drop from an enlarging, green, weakly six-sided ovary. The ovary becomes a half-inch-tall, ovoid fruit, widest just below the middle and pointed at the tip. The immature green fruit becomes purplish to whitish with maturity, at which point it loosens off the stem and disintegrates to expose 20 or so smooth, brown, ovoid seeds with large fleshy white appendages (elaiosomes). These elaiosomes, a food source for ants, are carried, with seeds attached, into the ant colony. After removal of the elaiosomes, seeds are discarded by the ants. Thus, ants obtain food and the trillium has its seeds dispersed (an example of myrmecochory).

Green Trillium - Trillium viridescensPhoto 5: Immature ovoid fruits are surrounded by persistent sepals and leaves. Plant in background with palmate leaves is tall thimbleweed (Anemone virginiana), a common associate plant in the wild. Photo taken in early May.

Green Trillium - Trillium viridescensPhoto 6: Fruit disintegrates to expose smooth, brown seeds with white elaiosomes. Inset shows seeds with elaisomes. Photo in late June.

Green trillium is a great shady-garden plant that provides springtime interest. It is a long-term perennial that forms a compact colony over time. It is maintenance free and provides an excellent example of myrmecochory.

In addition to green trillium, five additional species of trillium are recorded from Arkansas: white or nodding trillium (Trillium flexipes), Ozark trillium (Trillium ozarkanum), purple trillium (Trillium recurvatum), wakerobin or toadshade (Trillium sessile), and Texas trillium (Trillium texanum). Green trillium can be distinguished from these by the combination of long, narrow and upright green to purplish petals, sessile leaves and flowers, and greater height.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Downy Serviceberry

Downy serviceberry (Amelanchier arborea) of the Rose (Rosaceae) family is a small tree or large shrub that produces showy white flowers very early in spring. The genus name likely originates from a common name of the type species of the genus, Amelanchier ovalis, a European species. The specific epithet translates to “tree-like”. Downy serviceberry is the most widespread species of the genus in North America, found throughout the eastern U.S. from Texas to Minnesota and thence east and south to the Atlantic and Gulf coasts. In Arkansas, where it is the only native Amelanchier, downy serviceberry occurs statewide except for lowlands of the Mississippi Alluvial Plain and West Gulf Coastal Plain. Other common names include common serviceberry, sarvisberry, sarvis, shadbush and Juneberry*.

Habitats of downy serviceberry include dry to mesic yet well-drained upland woodlands and forests, in full to partial sun light. It is especially common on ridgetops and rocky slopes. It often occurs as an understory tree among various hardwoods and pine. Downy serviceberry readily hybridizes with other Amelanchier species where ranges overlap.

Downy serviceberry, a deciduous tree to large shrub (referred to as “tree” herein), tends to have several trunks of varying size and, when younger, may sprout nearby suckers. Mature trees in full sun have a thickly branched, rounded crown, while those in shadier understories tend to be tall with irregular branching. An average size large tree is 15 to 25 feet tall (state champion tree is 44 feet tall). Branches tend to diverge from the parent branch at a sharp upward angle. Spring twigs, green and covered with long white hairs, grow from previous year’s brown to purplish, glabrous stems. Older twigs are smooth with white lenticels scattered about the ash-gray slender branches. Younger portions of trunks are smooth with splotches of grays and whites on a light gray background. Older trunks are a dark gray with shallow fissures.

Serviceberry - Amelanchier arboreaPhoto 1: Main trunks are furrowed while smaller trunk to right is smooth with splotches of lighter color. Lowest portion of central main trunk is 18 inches in circumference.

Overwintering buds are both apical and lateral. Apical buds, round in cross-section and with elongate pointed tips, are protected by 6 to 8 imbricated scales. With approaching spring, apices of interior scales grow to ½ inch so that they have brown bases and yellow-green to reddish tips. Lowermost scales remain brown and stubby at about ⅛ inch long. Interior scales have long hairs on their margins (ciliate). Scales fall off as spring growth emerges. Where buds include rudimentary stems and inflorescences, the inflorescences (attached to a mid-point of the new stem, opposite a leaf) emerge first, with the stem quickly following after flowers pass anthesis.

Serviceberry - Amelanchier arboreaPhoto 2: In this early February photo, imbricated bud scales are elongating as enclosed rudimentary inflorescence and stems develop. Upper surface of two fallen leaves shown on left. Lower surface of leaves shown on right.

Inflorescences consist of ascending to drooping racemes, up to four inches long, bearing up to a dozen flowers on slender ¾- to 1½-inch-long pedicels; the longest pedicels are toward the raceme bases. The medium green peduncles and pedicels early-on are covered with long, dense, woolly (downy) white hairs. Each pedicel is subtended by a thin, lanceolate, wooly bract with an additional bract at mid-pedicel. These pedicellate bracts are colored in various shades of red and pink.

Serviceberry - Amelanchier arboreaPhoto 3: In mid-March, flowers of downy serviceberry are in bloom while nearby trees remain dormant. Before the advent of the exotic, invasive Callery pear, serviceberry was the first tree with showy flowers to bloom in the woods, earlier even than the wild plums.

Flowers have five strap-like to narrowly elliptical petals that at first form a tube, but then become reflexed. Petals are set in a light green to reddish, slightly woolly floral cup (hypanthium) rimmed with five prominent triangular sepals. These sepals at first support the petals when they are overlapped into a tube, but then sepals become fully reflexed as petals flare and also reflex. Petals, with rounded apexes and narrow bases, are well separated one from another with the triangular sepals positioned in between petals in star-like fashion. Flowers, 1 inch in diameter, have up to about 20 slender stamens with white filaments tipped with light yellow, knobby anthers that become brown as flowers pass anthesis. Stamens, exserted and radiating from flower center, surround four or more styles, also exserted, that connect to separate ovules within the hypanthium. Flowering extends over about seven days, depending on weather conditions. Trees in sunny sites produce more numerous flowers than those in shady understories.

Serviceberry - Amelanchier arboreaPhoto 4: Racemes of flowers that are approaching anthesis. Previous year’s stems are brown to purplish, while older stems are gray.

Serviceberry - Amelanchier arboreaPhoto 5: Pedicels, peduncles, margins of bud scales and pedicellate bracts are woolly. Bud at left shows that the inflorescence is fully developed before the stem (to which inflorescence is attached) becomes evident.

New leaves are borne on stems that develop from apical and lateral buds. When a bud produces both a stem and a raceme, the raceme is terminal on the new stem. Although flowering mostly precedes stem and leaf growth, by the time of peak bloom, early new leaves are readily apparent.

Leaves, on slender reddish petioles, are alternate and thin to papery. Leaves are simple, oval to obovate with finely serrated margins with serrations generally extending from the rounded to mostly slightly cordate bases to the acute to acuminate tips. The teeth are sharply pointed. Mature leaves and their petioles are about 4 inches long and 2 inches wide. Leaf blades remain roundly up-folded along the midvein. The upper blade surface is generally glabrous while the lower blade may be densely pubescent early-on, but becomes mostly glabrous later in the growing season. Petioles, ¾ to 1½ inches long, also lose their downy hairs with age. Mature leaves are dull medium green above and slightly paler below with pinnate veins that are a light green. Downy serviceberry has good fall color that varies from yellow-orange to reddish. A few dead leaves remain on branches into mid-winter.

With fertilization, the inferior ovary enlarges to produce the apple-like fruit, a pome. Fruits are topped by triangular sepals. In June, green pomes become reddish black at maturity with a diameter of ¼ to 3/8 inch. Pomes, a favorite food of many birds and mammals, enclose four or more tiny stones.

Serviceberry - Amelanchier arboreaPhoto 6: In early May, the fruit cluster is attached opposite a leaf on the lower portion of the new stem. Up-folded leaf blade along midrib, serrated margins and venation can be seen.

For a native plant garden or natural area, downy serviceberry’s adaptability to various sites and soils, structural appeal, early bloom, tidy leaves and nice fall color make it ideal where a small tree is desired. The tree provides interest in all seasons and its fruit is much loved by wildlife and people–however, the stones are rock-hard, so chew cautiously.

  • The origin of “serviceberry” is debated. Some suggest that the name ties the tree’s early bloom to church or burial services in the New World. However, due to the moniker “serviceberry” having already been in use in the 16th century, it is more likely that it originates from “sarvis”, a corruption of “sorbus”, the ancient Latin name of a European species of mountain-ash with similar fruit.

“Shadbush” (or “shadblow”) is a reference to shad (an eastern fish) that swim upstream around the time that serviceberry is in bloom.

“Juneberry” is a reference to fruit being ripe in June.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Rose Vervain

Rose vervain (Glandularia canadensis, formerly Verbena canadensis) of the Vervain (Verbenaceae) family is an herbaceous, low-growing plant with spikes of showy flowers. The genus name refers to glands found on many of the species. The specific epithet refers to the species’ occurrence in what was historically considered to be Canada but is now part of the northeastern U.S. (it does not occur in Canada, as known today). The species occurs from New Mexico and Colorado, northeast to Minnesota, then east to New York and thence south and east to the Gulf and Atlantic Coasts. In Arkansas, it occurs statewide except for portions of the Mississippi Alluvial Plain. Other common names include rose verbena, trailing verbena and clump verbena. Preferred habitats are sunny to mostly sunny, mesic to dry rocky sites in woodlands, glades, prairies, sand hills and disturbed areas where soils may be thin and competition by other plants is limited.

An established plant develops a central ascending stem to 1½ feet long along with an apron of ground-hugging stems growing off the caudex. Ascending stems develop long lateral stems, and all stems eventually recline along the ground, with roots developing where stems contact the soil. Where stems become rooted, additional ascending stems may develop. Over winter months, portions of stems that are elevated above the soil (or not covered) freeze, while ground-hugging stems survive and actually continue to grow, producing short lateral ground-hugging branches that will produce apical flower spikes in spring. After fruits have been produced, fruit-bearing stems develop lateral branches that intermix with the central ascending stems noted above. Thick mats may form. In areas of especially harsh winters, rose vervain may survive only as annuals

Rose Vervain - Glandularia canadensisPhoto 1: This late-January photo shows a single, newly rooted stem that produced a flower spike the previous year (dead stem at upper left). Thereafter, lateral axillary stems developed that will produce apical flower spikes in the current year.

Stems, varying from dark green in spring to purplish in winter, are densely pubescent. Persistent stem pubescence is at first soft (villous), but becomes scabrous as stems become somewhat woody with age. Smallest stems may appear to be round (terete), but larger stems have four rounded sides.

Rose Vervain - Glandularia canadensisPhoto 2: In late January, previous year’s stems (purple) that were elevated were subject to freezing while ground-hugging stems thrived, producing new side stems with fresh leaves.

Leaves of rose vervain, broadly lanceolate in outline and loosely up-folded along midveins, are dark green above and a lighter green below. Leaves, up to 3 inches long and broad, are widest at the base with a gradual tapering to a gently-pointed apex. Leaf margins have prominent, equal-sided, blunt-tipped teeth (dentate margins) with the leaf apex having a similar tooth. One to several opposite pairs of shallow to deep clefts may occur between marginal teeth with deeper clefts near the base. Venation is off-set pinnate with secondary branched veins terminating at tips of marginal teeth. Veins are suppressed above (with a sunken upper midvein) and expressed below. The blade surface between secondary veins is bullate (raised). The upper leaf surface has scattered short pubescence across its surface while longer lower leaf pubescence occurs along veins. Leaves have ½ to ¾ inch grooved petioles. Leaf blades continue down petioles (decurrent) as very narrow wings that gradually disappear toward petiole bases. Petioles, with a flat grooved upper surface, have long ciliate pubescence angled toward the leaf blade and shorter flattened underside pubescence.

Flower buds, at the ascending tips of the ground-hugging branches, become apparent in mid-winter. The principal bloom period is in early spring with first flowers typically opening about mid-March. Flowering continues for up to two months and, thereafter, depending on weather, blooms may occur sporadically into fall. At first, flowers seem to be in 2-inch-wide domed clusters, but with flowering advancing as the rachis elongates, the true spike arrangement becomes apparent. Spikes, stout and pubescent, may be 5 inches long (including a 2 inch peduncle) with ten to thirty flowers. By the time the uppermost flowers are at anthesis, the lowermost flowers already bear immature fruit.

Rose Vervain - Glandularia canadensisPhoto 3: Lavender flower buds appear from calyxes rimmed with linear tooth-like lobes. Note leaf shape, venation and pubescence as well as glandular pubescent calyx lobes. Photo in mid-March.

Flowers, to ½ inch across, have slender ½-inch-long corolla tubes that flare out 90 degrees at the throat before dividing into five ¼-inch-long lobes (salverform shape). Lobes have wide bases and wider, wavy and notched apexes. The lavender to purple flowers have a throat opening that is edged in a darker color as well as covered by an encircling thick fringe of ascending hairs (floccose). Corollas are set in slender, densely glandular-pubescent, medium green, ascending, ribbed calyxes that are rimmed with five long, purplish, linear to lanceolate tooth-like lobes. Half of the corolla-tube length extends beyond the calyx.

Rose Vervain - Glandularia canadensisPhoto 4: Early flowers of two spikes are shown along with a developing spike (upper left center). Flowers have long corolla tubes (see lower flower of upper spike). Leaves of this plant are more elongate than plant in previous photo.

Rose Vervain - Glandularia canadensisPhoto 5: Throats of flowers are covered by a thick fringe of hair so that reproductive parts cannot be seen.

A pistil and four stamens of the perfect flowers remain hidden within the floccose corolla tube. Stamens occur in two pairs, with one pair bearing large anthers above a two-lobed stigma while the second pair of large anthers is below the stigma. Stamens are a light green with slightly yellow anthers; style and stigma are also light green. Stamens, with short filaments, are adnate (fused) to the upper portion of corolla tube. The corolla tube has internal, decurrent pubescence below the stigma. The ovary comprises four “knobs” (each with a single ovule) with the style attached at the ovary’s depressed center.

With fertilization, ovules become seeds within the four nutlets of the fruit. Individual nutlets, about 1/8 inch long, have an elongate cylindrical shape. Nutlets have a round apex and truncated base. Most of surface is covered with small longitudinally arranged pocks, except for the relatively narrow section where the nutlets join. Dry seeds are dark brown overall with lighter coloration where nutlets join.

Rose vervain is an ideal plant for borders, rock gardens and containers. It can develop into an attractive ground cover with a heavy bloom in early spring and occasional later blooms. As spring approaches, frozen stems can be clipped off for a better floral display. Flowers are similar to phlox species, but phlox leaves are linear and smooth-margined.

Rose Vervain - Glandularia canadensisPhoto 6: Rose vervain in a sunny rock garden setting. Photo in late March.

Other species of the genus found in Arkansas are Dakota vervain (Glandularia bipinnatifida var. bipinnatifida, a native species of conservation concern that is recorded from Blackland Prairie sites in four southwestern counties), moss vervain (Glandularia pulchella [= G. aristigera], a non-native species recorded from a few scattered counties), and pink vervain (Glandularia pumila, a native species recorded from one southwestern county). Rose vervain can be readily distinguished from Dakota vervain and moss vervain by its more coarsely divided leaves and from pink vervain, an annual, by its larger, more purplish flowers.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Eastern Prickly Pear

Eastern prickly pear (Opuntia humifusa, formerly Opuntia compressa)* of the Cactus (Cactaceae) family is a mostly prostrate stem-succulent with large, bright yellow, spectacular flowers. Like most members of its family, the species is adapted to thrive in arid habitats. Interestingly, the cactus family (with the exception of a single species) is native only to the New World. Cactus-looking plants in African and Asian deserts typically belong to either the Spurge (Euphorbiaceae) or the Milkweed (Asclepiadaceae/ Apocynaceae) families.

The genus name, Opuntia, originated in the first century for a cactus-like plant found near Opus, Greece. The specific epithet “humifusa,” from Latin for “spread out,” refers to the plant’s growth habit. Eastern prickly pear, the most widely spread cactus in the eastern U.S., occurs from New Mexico and Colorado east to Connecticut and south across all interior states to the Atlantic and Gulf Coasts. In Arkansas, it occurs across the state except for the Mississippi Alluvial Plain and lower elevations of the West Gulf Coastal Plain. Other common names include devil’s-tongue and common prickly pear.

Eastern prickly pear occurs as scattered individual plants or may form a mat-like colony over time. A succulent species, it is highly tolerant of drought and, unlike most cacti, cold temperatures. It grows well in a wide variety of habitats, varying from full-sun rocky hillside glades and sandy prairies to woodland openings with partial sun. Plants do well in xeric to dry-mesic soils that may range from acidic to alkaline. Plants in areas of encroaching tree cover often die out due to lack of sunlight.

Prickly Pear - Opuntia humifusaPhoto 1: This two-year plant has a round stem at its base and a broadened stem above. With maturity, fewer spines will be present.

Eastern prickly pear is composed mostly of water-storing stems with the lowermost portion being round in cross-section while the remainder of stem comprises thick, flattened, oval to obovate segments (pads or cladodes) that grow chain-like from the upper margin of one pad to the next. Stems to 3 feet long are prostrate, except for terminal pads that may stand up to 8 inches or so. The lowermost portion of the stem extends into soil as a stub from which a few long fibrous roots extend out at shallow depth for several feet. Size of pads is dependent on habitat, but pads may be 5 inches long, 3 inches wide and ½ inch thick. New pads, growing from the distal margins of previous year’s pads, break-off easily and, when in ground contact, can root to form a new clonal plant. The lowest portions of mature plants become woody.

During the growing season, mature pads have a medium green to blue-green waxy, glabrous surface marked by regularly arranged areoles positioned diagonally across both sides of pads and also along upper pad margins. All areoles have tight tufts of short hair-like reddish bristles (glochids) with barbed tips. Areoles on upper sides of pads and along upper pad margin may bear one or two light-colored, stout, needle-like spines to 3 inches long (spines sometimes absent on pads or entire plants). Areoles along upper margins of pads also produce new pads or flowers (see below). Both glochids and spines are painful to human touch; however, the short glochids can be more painful due to their flesh-retaining tips. They are also much more difficult to remove. During drought and with approaching winter, pads lose water content and become thin and wrinkled, but quickly revive with improved conditions.

Prickly Pear - Opuntia humifusaPhoto 2: This plant, which may be four years old, does not have any spines. Note the diagonally arranged areoles with tufts of glochids. Photo in late August.

When new pads develop, side and marginal areoles bear single, short, narrowly conical (subulate) ¼ inch, more or less, vestigial leaves. These leaves quickly drop off, leaving all food-making function (photosynthesis) to the green stems.

In late May into June, solitary flowers grow from areoles along the distal curved margins of previous year’s pads. Multiple flowers may grow from a pad. Early on, flower buds have light green triangular sepals that cover several overlapping series of tepals (sepals transitioning into petals). Flower buds are prominent with a short-conical shape (when seen from side) and are positioned at the tip of inverted-cone-shaped elongate ovaries that are several times longer than buds. Ovaries are glabrous with diagonally arranged, well-spaced, spineless areoles along with a ring of areoles outlining the wide, distal end. The ovarian areoles have the same leaves as new pads, but without spines. Ovaries are slightly ridged.

Prickly Pear - Opuntia humifusaPhoto 3: In this mid-May photo, a previous year’s pad bears a new pad and two flowers growing from areoles at its upper margin. Areoles of new pad bear short conical leaves that will quickly drop off.

At anthesis, the perfect (with male and female parts) diurnal flowers, to 3 inches across, show light to bright yellow overlapping waxy petals. The eight or so petals in the upper series have narrow bases and a broad upper portion with a central point and often two side points. Uppermost petals may or may not be marked by a reddish-orange “flame” that extends upward from the base. Underlying series of petals gradually change shape, grading into the lowermost series. Flowers have numerous short stamens, with light yellow elongate anthers on darker yellow filaments, that encircle a single, white, stout style tipped by a bulbous partitioned stigma.

Prickly Pear - Opuntia humifusaPhoto 4: This orange-centered flower has three points on its petals. Triangular green sepals can be seen on the bloomed-out flower to the right. A young pad behind this flower still bears its small conical leaves.

Spent flowers quickly fall from the ovary (developing fruit), exposing a concave scarred upper surface. As the elongate fruit (berry) matures, it becomes fleshy and purplish. Fruits remain on the stem into the next growing season. Fruits contain 20 to 30 light colored, flattened and circular seeds that have an indentation on one margin and a protruding edge all around. Seeds are dispersed by small mammals and birds.

Prickly Pear - Opuntia humifusaPhoto 5: Central pad bears five flowers and no new pads. Light colored lines across old pads may result from pad shrinkage during winter or droughts. Photo in early June.

Prickly Pear - Opuntia humifusaPhoto 6: In this early January photo, the two fruits are 2½ inches long and ½ inch in diameter. Inset shows seeds in a fruit as well as three cleaned seeds that bear imprint of embryonic plants.

In a garden setting, eastern prickly pear may be suitable for xeriscape and rock gardens where the plants could remain untouched and where other vegetation would not invade the area. Plants can be easily started by setting the end of a detached pad at the chosen permanent site. Eastern prickly pear is a dependable bloomer. Fruit and pads of prickly pears are edible and may be found in grocery stores labeled “nopalito” (pads) and “tuna” (fruit). However, care must be taken to remove the glochids from pads of our native species.

Along with eastern prickly pear (Opuntia humifusa), a second native cactus occurs in Arkansas, namely, western prickly pear (Opuntia macrorhiza)*. This second species is recorded from scattered counties in the Interior Highlands. Opuntia macrorhiza, also known as plains prickly pear, has more than two spines per areole, with spines occurring in areoles across the entire pad surface. It is also sometimes reported to have thicker, tuberous roots in comparison.

*The taxonomy of the genus Opuntia is widely debated. The treatment presented here follows the traditional (and most simplistic) view of Arkansas prickly pears. However, some authorities believe we have several additional species within the state, but delineation of those species and the most appropriate application of names to those species is not settled. Some of those authorities believe we do not have true Opuntia humifusa in Arkansas, this being a species more confined to the Northeast. The name Opuntia cespitosa may sometimes be found applied to the common prickly pear in Arkansas traditionally called Opuntia humifusa. To make things even more confusing, hybrids have been reported within the genus.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Resurrection Fern

Resurrection fern (Pleopeltis polypodioides var. michauxiana), formerly Polypodium polypodioides, of the Polypody (Polypodiaceae) family is an evergreen fern that occasionally appears to die in periods of dryness while being “resurrected” when again moistened. The genus name is from Greek words meaning “many” and “shields” (see “peltate scale” below). The specific epithet is based on Greek words for “many” and “foot”, in reference to its rhizomes. In the U.S., resurrection fern is found from Texas to southeast Kansas to Delaware, thence southward to the Atlantic and Gulf Coasts. In Arkansas, it is known from every county. (The species, with its several varieties, has an extraordinarily wide range, occurring in South America south to Argentina as well as in Africa.) Other common names (based on its former classification) include little gray polypody and scaly polypody. Resurrection fern grows on living or dead tree trunks and branches, as well as on rocks. (Although resurrection fern is usually found growing on living trees, it is an epiphyte, not a parasite nor, like mistletoe, a hemiparasite. Plants get neither food nor water from their hosts, only a perch.) They derive much of their moisture and nutrients through their leaves from the air and surrounding dampness. They are often found in association with mosses. Sun exposure and available moisture are variable.

Resurrection fern is a low-growing, creeping plant with long, 1/16-inch-diameter, well-hidden rhizomes that follow surface irregularities of tree bark and other surfaces. Rhizomes, strongly attached to the host by roots, are covered with dense, thin, acicular  and light-colored scales. Rhizomes are profusely branched so that mats form in favorable sites, such as on tree trunks and across tree limbs.

Photo 1 Jul 2Photo 1: With dry conditions, fronds shrivel and curl with blade undersides turned upward. Photo in early July.

Photo 2 Jan 8Photo 2: In this early January photo, resurrection fern (growing among moss) was damaged when tree limb was cut for firewood, thus exposing rhizomes. Note linear scales pointing in direction of rhizome growth.

Leathery leaves (fronds), ascending or descending from the upper sides of the rhizomes, measure up to about 9 inches long and 2 inches wide. They are broadly lance-shaped and deeply once-divided (pinnatifid), with up to 15 or more pairs of alternate, blunt-tipped lobes (and a single terminal lobe at the apex). Fronds are glabrous and dark-green above and a light grayish-green beneath. Lobes, 1/8 inch wide, are oblong to elliptic with wide bases, entire or with slightly wavy margins, and are generally slightly wider at the middle, tapering gently toward the tip. Petioles (stipes), about a third the length of the frond, are round in cross section with a flattened top. Other than the midrib, which is depressed above and expressed below, the only other obvious venation is the midveins of the lobes, the lesser veins being obscure.

Although fronds may be green at any time of the year, during dry conditions, they shrivel (losing most of their water content*) and become grayish, turning their lower surface upward to better absorb incoming moisture. Upon return of moist conditions, scales on the lower surface absorb moisture and pass it on to the living tissues of the leaf–the “resurrection” of a withered, apparently dead organism into a lush green plant.

Photo 3 Dec 6Photo 3: An isolated fern colony anchored to a vertical rock outcrop.

The lower surfaces of the lobes are covered with small (1/16 inch), flat, overlapping scales, attached at their reddish brown centers (peltate) and surrounded by broad, transparent to light gray, more or less entire margins. Scales are numerous, variously sized, and concentrated along the blade’s midrib, from where they continue down the lower, rounded side of the stipe (petiole). The lower, rounded surface of the stipes also has dense, transparent, lanceolate scales and reddish brown hairs. The upper flat surface of stipes is glabrous.

Photo 4 Dec 6Photo 4: New fronds unfurl on which developing peltate and lanceolate scales can be seen.

Resurrection fern (and all other true ferns and their allies) produce new plants through spores**. Both fertile and sterile fronds have the same shape (monomorphic). In summer into fall, fertile fronds produce up to 80+ ball-shaped sporangia (structures in which spores develop) aggregated into discrete, flattened and rounded to oval “fruit dots” (sori). Fruit dots, on lower sides of lobes, tend to be on the upper ¾ of fertile fronds and on the upper half of their lobes. Fruit dots, near lobe margins, occur in rows on either side of the central veins. They develop without the protective cover (indusium) that is typical of many genera of ferns. Initially, sporangia are yellow but become brown as they mature and split open. With the splitting of the sporangia, dust-like spores are released to the breezes. The presence of sori on the underside of fronds results in a prominent raised area (pock) directly above it on the upper surface.

Photo 5 - Oct 14Photo 5: Upper side (left) and lower side (right) of fertile fronds. Pocks on left frond correspond to sori on the underside, as seen on frond at right. Frond on right shows, as well as sori, numerous peltate scales, which are found on fertile and infertile fronds. Photo in mid-October.

Resurrection fern can be “transplanted” by attaching a fern-bearing fallen tree limb to another tree or rock in a mostly shady, generally moist site. The fern-covered tree limb (or a fern division) must be firmly attached to its new host so that new rhizome growth will attach.

A second member of the Polypody family is also found in Arkansas, namely, rock polypody (Polypodium virginianum), and it may be mistaken for resurrection fern. Both species have similar leaf shape, but resurrection fern has narrower rhizomes and shorter fronds.  Fronds of rock polypody can be over a foot long.  The definitive characteristic to separate these two species is the peltate scales found on resurrection fern, but not on rock polypody. Also, rock polypody prefers consistently moist sites on rocky bluffs and boulders, rather than trees.  In Arkansas, it occurs primarily in the Ozark Mountains with a few occurrences as far south as Logan and Polk Counties.

  • Resurrection ferns can lose 95% of their water content and survive. Their cells have proteins (dehydrins) that, with increased numbers when the plant dries, concentrate along cell walls preventing cells from totally collapsing.

**  Spore-producing plants are called ” sporophytes”.  They represent the diploid phase of a complex life cycle that–you may remember from your last botany or biology course–goes by the name of “alternation of generations”. A spore germinates in soil to become a prothallus (the haploid or “gametophyte” phase of the life cycle), a thumbnail-sized, non-vascular, alga-like plant.  The tiny prothallus produces gametes: both mobile sperm and attached eggs.  With fertilization of the egg, a diploid zygote can develop into a new diploid sporophyte plant–and start the cycle over again.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Jerusalem Artichoke

Jerusalem artichoke* (Helianthus tuberosus) of the Aster (Asteraceae) family is a large, tuber-producing perennial that was an important food source for Native Americans and early settlers. The genus name combines two Greek words for “sun” and “flower”. The specific epithet is from Latin and means “with tubers”. This species occurs throughout the eastern U.S., as well as in eastern Canada, with scattered, presumably introduced occurrences in the western U.S. In Arkansas, it occurs across the northern half of the state and in scattered southern counties. Its preferred habitat is partially to fully sunny sites with moist loamy soils, such as found in creek and river floodplains and roadside ditches. Other common names include Canada potato, sunchoke (a commercial name), and girasole (Italian for “sunflower”).

In late summer into fall, in addition to the plant’s fibrous roots, thicker roots radiate out from the underground portion of the stem. These thicker roots terminate with light tan to reddish, stubby to elongate tubers that may be mostly smooth or knobby. Tubers may be 4 inches long and 2 inches across. These thin-skinned tubers are white and potato-like inside. Tubers, encircled by well-spaced growth rings, have a main bud at their distal end along with scattered secondary buds, especially on knobby projections. With maturity of tubers in mid-fall, parent stalks and roots die. Plants can produce numerous tubers so that thick colonies can grow over several years.

Jerusalem artichoke - Helianthus tuberosusPhoto 1: Along with a main bud (whitish tips), tubers also have smaller secondary buds. Growth rings encircle tubers. Upper large tuber is 2¾ inches long, ¾ inch wide. Photo in early December.

Spring growth, directly from over-wintering tubers, begins with appearance of leaves attached to a main stem. Through the growing season, stout erect stems may reach 4 to 10 or more feet. Round stems with short, stiff, white pubescence (scabrous) are generally a medium green but may be purplish. Main stems, to ¾ inch in diameter, feel bristly. Long branches grow from upper leaf axils, while short branches may grow from lower leaf axils.

Jerusalem artichoke - Helianthus tuberosusPhoto 2: Parent plant having died, new plants grow from tubers in mid-March.

Jerusalem artichoke - Helianthus tuberosusPhoto 3: Plants in this colony are showing early upper branches. Plants in foreground have been browsed by deer.

Leaves are medium green on upper surface and lighter green on lower surface, with an underside that is smooth due to soft pubescence and a scabrous upper side due to stiff, short pubescence. Leaves, widest at their bases, gradually taper to a point (acuminate). Largest leaves, typically occurring in opposite pairs below the inflorescence, are elongate-triangular with a blade up to 10 inches long and five inches wide on a 4-inch petiole. These largest leaves–pairs may be 5 or more inches apart along the stem–have a truncated base and serrated margins. Petioles of larger leaves are partially winged. Petioles of opposite leaf pairs are narrowly connected around the stem. Smaller alternate leaves, higher in the inflorescence and on short branches, are lanceolate with entire margins and have petioles that tend to be winged their entire length. Smaller alternate leaves also occur on short branches that occur below the inflorescence.

Primary venation consists of three prominent veins, namely a central vein or midrib and a pair of lateral veins that branch off midrib near its base. The two lateral veins gently curve toward leaf margin and continue in jagged manner parallel and close to the margin. Tertiary veining is offset pinnate. Veins are weakly depressed above and strongly expressed below.

Inflorescences of Jerusalem artichoke, in late summer into fall, consist of composite flower heads at the ends of stems and branches. The first flower heads to reach anthesis on the main stem or floral branches are the terminal heads. By the time the terminal flower head of the main stem or a branch is in bloom, heads on floral branches are already close to bloom. Depending on habitat and colony density, a plant may produce from several to 15 or more heads over a month or more.

Jerusalem artichoke - Helianthus tuberosusPhoto 4: Flower head bud on this 7-foot tall plant terminates the main stem. Secondary stems, as can be seen growing from leaf axils, will quickly also produce flower heads.

Flower heads, varying from 2½ to 4 inches wide with a disk varying from 3/8 to 5/8 inch wide, consist of 12 to 20 infertile ray florets and 50 or more fertile bisexual disk florets. Ray florets have a strap-like, yellow, pleated ligule with a rounded tip. Yellow, ¼ inch long disk florets are tubular with five flared lobes. Stamens of disk florets have dark anthers, connate to each other and arranged in columnar fashion around the style. Styles have a long, split (bifurcated) stigma whose branches coil backwards. Florets are set on a convex receptacle supported by a rounded involucre comprising about 30 overlapping, lanceolate-triangular phyllaries in several series. Phyllaries, slightly darker than the peduncles, have short pubescence, similar to that of the peduncles. Lower portions of phyllaries are appressed while long tapering ascending tips are flared to reflexed. In cross-section, the flower head is round. Peduncles, subtended by small leafy bracts, have the same appearance as their supporting stem or branch, including short pubescence.

Jerusalem artichoke - Helianthus tuberosusPhoto 5: Long, mostly leafless floral stalks terminate with a single flower head. Scabrous stems and branches may be purplish. Photo in mid-September.

Jerusalem artichoke - Helianthus tuberosusPhoto 6: Styles of disk florets become exserted above the dark anthers. Stigmas divide and coil backwards.

Jerusalem artichoke - Helianthus tuberosusPhoto 7: Phyllaries in several series form the involucre. Wide lower portions of phyllaries are appressed while long tapering tips are flared to reflexed.

Fertilized disk florets produce ¼ inch long, flattened, grayish achenes (dry one-seeded indehiscent fruits) tipped with two small quickly-dropped bristles. The principal source of reproduction is vegetatively via the tubers.

Jerusalem artichoke - Helianthus tuberosusPhoto 8: In this early November photo, with flower heads drying, large leaves (upper and lower surface shown) are about to drop while leaves on small axillary stems remain green. Achenes shown in inset. (A potter wasp [Eumenes sp.] built an urn of mud for one of its offspring on underside of large leaf on right.)

For a garden or natural area with mesic soil, Jerusalem artichoke, with its tall large-leafed stems and showy flowers, would be striking. However, stems may need to be staked and chemical control may be needed to prevent aggressive spreading by tubers. Tubers, high in dietary fibers (inulin) and minerals, may be eaten raw or variously cooked.

In addition to Jerusalem artichoke, 15 other types of Helianthus (sunflowers) occur in Arkansas. Jerusalem artichoke has characteristics that may cause it to be incorrectly identified as one of three woodland sunflowers (Helianthus strumosus, Helianthus divaricatus and Helianthus hirsutus). Jerusalem artichoke, typically found in more moist sites, tends to be a stouter and larger plant with larger stem leaves that have longer petioles. Tubers, found on Jerusalem artichoke in fall and winter, do not occur on the three woodland sunflowers. For articles regarding the woodland sunflowers, see here and here.

  • Jerusalem artichoke, a native of North America, was an important food for Native Americans and early colonists. It was introduced to Europe where it became widely used for human and livestock food. The “Jerusalem” moniker is believed to be a corruption of the Italian word for “sunflower” (girasole, pronounced “jeer-uh-so-lay”). Jerusalem artichoke is not a true artichoke (Cynara cardunculus var. scolymus), but its tubers are said to have an artichoke flavor.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – American Holly

American holly (Ilex opaca var. opaca*) of the Holly (Aquifoliaceae) family is a broad-leaf evergreen tree frequently used for Christmas decorations. In the U.S., it occurs from Texas to Illinois east to Massachusetts and thence south and east to the Atlantic and Gulf Coasts. The genus name comes from scientific name for holm oak (Quercus ilex), which has broad evergreen leaves. The specific epithet “opaca” is a Latin word meaning dull or opaque (referring to the leaves), not glossy or transparent, in contrast to European species. In Arkansas, American holly is found throughout much of roughly the southeastern two-thirds of the state. In its native habitat it is found mainly in the understory of hardwoods and pines in moist, well-drained soils of rich lowlands, stream terraces, on northern slopes and along swamp margins. Other common names include Christmas holly, white holly (for its wood color), and evergreen holly.

American holly may reach 40 to 50 feet tall and, occasionally, taller**. Trees generally have a straight central trunk 1 to 3 feet in diameter, with several main branches in mid to upper portion. New spring branches, straight and slender, with minute short pubescence, are green at first, becoming light gray at the end of the growing season and, thereafter, a darker gray with lighter, often silvery blotches. With short, stout, stiff and crooked branches with similar growth rate along its entire height, trees are typically pyramidal with a rounded top. Young trees in full sun, which have branches to the ground, tend to be compact and densely branched while those in more shady settings have fewer branches and a more open structure. With age, lower portions of trunks becomes branch-free and upper branching becomes more open. Trunks have thin, gray bark that is usually smooth. Growth rate varies from slow to moderate, depending on habitat quality. American holly can survive Arkansas’s harshest winters, but does not survive fire or long-term soggy soils.

American Holly - Ilex opaca var. opacaPhoto 1: Thin bark may be smooth or rough. Trunk diameter of a young tree at left is 5 inches while diameter of tree on right is 1 foot 9 inches.

American holly has evergreen leaves that appear in early spring and drop off two springs later, about a month after new leaves have appeared. New spring leaves are a bronzy green that quickly changes to a medium green. Mature leaves have a slightly shiny upper dark green surface and a dull yellowish green lower surface. Leaves, alternate and elliptical in general outline, have thick stiff blades that range from 2 to 4 inches long and half as wide. Leaves bow-up from mid-rib to blade margins so that the blade is an elongated “bowl” (top convex and bottom concave), with a slightly billowy blade surface between secondary veins. The blade is stout enough that when the upper surface is pressed down, it springs back to its original shape. Blade margins typically have straight, sharp, stout, well-spaced, outward-pointing, sixteenth-inch, light-colored spines, along with an equally-sized spine at leaf apex. When spines are present, 3 to 6 pairs typically mirror across mid-rib. Narrowly revolute (turned under) leaf margins are wavy, when seen from above, with a spine tipping each wave. Bases of leaves are rounded to wedge-shaped. Petioles are relatively short at about ½ inch long on four-inch-long leaves. Upper mid-rib is boldly channeled and light colored while the mid-rib of lower surface is prominently exserted and light colored. Secondary, closely-spaced pinnate veins are obscure.

American Holly - Ilex opaca var. opacaPhoto 2: In spring, bronzy leaves grow from new green branches while dark green leaves from previous spring remain on gray branches. Yellowing leaves in background, about to drop, grew two years earlier. Photo taken mid-April.

American holly is dioecious (female and male flowers on separate trees). Female flowers typically occur singly on pedicels, but in groups mostly below terminal leaves of new twig growth. Fragrant male flowers occur in cymes comprising up to eight flowers, often in elongate clusters, from axils of current or previous years’ leaves or directly from current year’s stems. Inflorescences growing directly from new stems are subtended by elongate, weak bracts that quickly drop. Female and male flowers, of about the same size (¼ inch diameter), have four equally sized, spreading, white petals with cupped-tips. Female or pistillate flowers have four white infertile stamens positioned around a prominent ovary, while male or staminate flowers have four fertile stamens positioned around a small rudimentary pistil. Anthers of female flowers are tipped with a flattened white flange. Fertile oblong anthers of male flowers, bearing yellow pollen, face inward (introrse). Stamens of male and female flowers are positioned between the petals. Barrel-shaped bright green ovaries of female flowers have large, round, flattened, convex, yellow-green and sessile (no styles) stigmas. Petals are set in a small, pale green, four-lobed, persistent calyx.

American Holly - Ilex opaca var. opacaPhoto 3: These male flower buds, in cymes or cymose clusters, grow from old leaf axils, from new leaf axils, or directly from new stems. Leaves in the inflorescence typically have few spines. Photo taken late April.

American Holly - Ilex opaca var. opacaPhoto 4: Female flowers typically grow singly on pedicels but in groups positioned mostly below terminal leaves of new twig growth. Infertile stamens are tipped with an infertile flange. Photo taken first of May.

American Holly - Ilex opaca var. opacaPhoto 5: Display shows pistillate (female) inflorescence on left and staminate (male) inflorescence on right. Note infertile stamens of female flowers and infertile ovary of male flower.

Female trees produce round to slightly oblong, berry-like fruits (drupes) on short spindly stalks attached directly to branches. Immature green fruits mature to a low-gloss red (occasionally yellow) in November. Showy mature, firm fruits, ¼+ inch in diameter, contain four to six nutlets grouped into a circular shape, like the sections of citrus fruits. Red (or yellow) skin of fruit encloses dry yellowish pulp. Relatively small, persistent, four-sided calyxes are set tight against the fruit. The surface of light-tannish, three-sided (one rounded side and two flats sides) nutlets have longitudinal ridges. Fruit remains on trees through winter, unless eaten by birds. Nutlets are dispersed by local and migrating birds and small mammals.

American Holly - Ilex opaca var. opacaPhoto 6: Display of upper and lower leaf surfaces and fruits. Remnants of calyxes persist at base of fruits as a small yellowish square. Note obscure secondary pinnate veins and small terminal bud. Photo taken mid-December.  Inset shows occasional yellow fruit.

With its outstanding winter characteristics (green leaves and red fruit), American holly is often planted in the home landscape. When sufficient space allows for a large tree and its spiny leaves would not be a problem, the tree should be welcomed in a natural area or woodland garden. As broadleaf evergreens, both male and female trees are great winter accent plants, especially showy on a snowy day. Fruits are an important winter food for many song and game birds and small mammals. For a “clean” trunk, lower limbs may need to be removed.

American Holly - Ilex opaca var. opacaPhoto 7: Mature trees in home landscapes.

  • A second variety of American holly, native to the U.S., is Shrub or Dune Holly (Ilex opaca var. arenicola). It occurs in dry sandy sites in Florida.

** Arkansas’s Champion Tree, in White County, is 63 feet tall with a diameter of more than 4 feet.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Rusty Blackhaw

Rusty blackhaw (Viburnum rufidulum) of the Arrow-wood (Adoxaceae) family, formerly of the Honeysuckle (Caprifoliaceae) family, is a small deciduous tree or large shrub (referred to as “tree” herein) with a year-round attractive appearance. It occurs in the U.S. from Texas to Kansas to Ohio to Virginia and thence into states along Atlantic and Gulf coasts. In Arkansas, it occurs statewide. Viburnum is the classical Latin name for this group of plants. The specific epithet means “rusty colored” in reference to the buds and leaf pubescence. Other common names include southern blackhaw, rusty nannyberry and blue haw. It grows in a wide variety of well drained soils in upland sites ranging from open woods and woodland edges to fence rows.

Rusty blackhaw reaches 15 to 25 feet tall, the taller trees growing in well drained, mesic soils. Plants usually have a single, low-limbed trunk to 6 inches in diameter, but may produce suckers that result in tight groves. New branches in spring originate either immediately above the previous year’s leaf scars or as adventitious buds that “sprout” on upper sides of older branches. New branches have pairs of lateral leaves that are evenly spaced and off-set 90 degrees from pair to pair. In a branch’s second growth year, new short and stout lateral branches (twigs) grow perpendicularly to the parent branch from axillary buds immediately above leaf scars. Branches have thin, smooth, gray bark at the end of their first growth year and later roughen and develop darker raised and irregular lenticels (pores). As upper branches age over a number of years, they become arched and the crown becomes rounded to irregular. The trunk and lower portion of vigorous branches, as they increase in girth, become vertically and horizontally fissured, creating a blocky appearance. Branches and trunks are round in cross-section.

Rusty blackhaw - Viburnum rufidulumPhoto 1: Branch on right has bark with early fissuring and small, rough lenticels. Trunk on left, 3 inches in diameter, has fissured, blocky bark.

In late fall, current and past year’s branches have apical and lateral buds. Larger apical buds (to ¼ inch long) project directly out from branch tips while smaller lateral buds are pressed against the branch. Buds have several pairs of rusty-colored scales (each pair offset 90 degrees) that meet edge-to-edge (valvate). The outer pair of scales has very short, velvety, rusty-colored pubescence while underlying pairs are less velvety. Apical buds have a flattened spear shape; larger apical buds with a truncated base enclose rudimentary flowers.

Simple, leathery, opposite leaves, up to 3+ inches long and 2½ inches wide, are mostly oval to obovate, but some at ends of branches may be elliptical. Petioles are short (to ½ inch) with flat to grooved upper surfaces. Petioles angle upward, but leaf blades twist toward the horizontal for best sun angle. Leaves in sunnier sites are more leathery and have a dark green and glossy upper surface and a lighter green lower surface. Leaf margins of trees in sunnier sites are jaggedly serrated and may be crinkled, while in shady sites, serrations are smaller and leaves are thinner. Leaf blades may extend a short distance down petioles. Venation, depressed on the upper surface, is pinnate with secondary veins disappearing before reaching leaf margin. Tertiary veins form a rectangular-pattern. Early in the growth year, rusty pubescence may be found on the petiole and underside of the leaf, especially along central and secondary veins. In fall, leaves display various shades of pink, red and purple.

Rusty blackhaw - Viburnum rufidulumPhoto 2: Upper stem resulted from current year’s growth while lower stem-segment exhibits four years of growth. Larger buds enclose rudimentary flowers. Shape of larger leaves, as shown, is typical while smaller elliptical leaves, as shown, are near ends of branches and twigs.

Rusty blackhaw is at peak-bloom by the first of spring when new leaves are fully unfurled. Inflorescence consists of convex cymes of closely spaced white flowers in clusters on a half dozen or so green, upright floral branches, which are also branched. Cymes, even occurring on shrubbier plants, are abundant and well spread over exterior of the tree. A cyme, to 5 inches across, may have 150 or more flowers that reach anthesis at the same time.

Rusty blackhaw - Viburnum rufidulumPhoto 3: In mid-April, cymes are positioned above new leaves. Leaves have a shiny surface and reddish petioles.

Flowers, ¼ inch across, are bisexual with a white corolla that has five broadly-rounded and widely-flared lobes. Five stamens, alternating between lobes, have white to translucent slender filaments bearing pale yellow two-part loosely attached anthers. Pale yellow stubby ovaries are topped by a short thick style and a flat stigma.

Rusty blackhaw - Viburnum rufidulumPhoto 4: Flowers have white corollas with five spreading lobes, exserted anthers and a stubby ovary.

In late summer, cymes have a short (¼ inch) woody base topped by 1½ inch long floral branches which have become reddish and droop due to fruit load. A few to a dozen or more fruits typically are produced on a cyme. Fruits are rounded-elongate (½ inch long and ¼ wide), glabrous (hairless), fleshy drupes, each with a single stone. Drupes, at first a light to medium green, become pale red before turning blue and then a shiny blue-black that is dulled by light blue haze (a waxy “bloom”). Juicy purple pulp of mature drupes becomes mealy as drupes wrinkle at final maturity. Fruit is persistent into early winter.

Rusty blackhaw - Viburnum rufidulumPhoto 5: With fertilization, ovary enlarges to a round-elongate fruit. Photo – late May.

Stones (3/8 inch long by ¼ inch wide) have a flattened, oval shape with a small point at one end. One side has a raised longitudinal middle section while the other side has a corresponding sunken section. Stones cleaned of pulp remain a dark blue color; however, true stone color is a medium tan.

Rusty blackhaw - Viburnum rufidulumPhoto 6: In fall, fruit changes from pale red to blue-black with light blue waxy haze (bloom). Floral branches become red. Photo – early November.

For a garden or natural area, rusty blackhaw is an excellent choice. It would do well in a rocky area in full sun to partial sun. A long-lived small tree with attractive leaves, plants produce a large number of white cymes in early spring and a striking, colorful display in fall. In winter, it exhibits interesting structure. Lower limbs may need to be removed to form a clean trunk for a tree and, if suckers appear, they may be removed. The fruit is also an excellent food source for birds and small mammals.

At least nine other members of the genus are found in Arkansas. The Arkansas species that most closely resembles rusty blackhaw is blackhaw (Viburnum prunifolium) which has very similar structural, flowering and fruiting characteristics, but tends to favor moist valley soils in the Interior Highlands (primarily in the Ozarks and Boston Mountains, but also with scattered occurrences in the Ouachitas). Leaves of Viburnum prunifolium tend to be thinner and more elongate, with smaller marginal serrations and pointed apices–somewhat plum-like. Rusty blackhaw can be identified by its rusty colored winter buds, mostly oval to obovate leathery leaves, shiny upper leaf surface and early rusty pubescence on leaves.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Drummond’s Aster

Drummond’s aster (Symphyotrichum drummondii) of the Aster (Asteraceae) family is a herbaceous perennial with disk flowers that change color with age. Preferred habitats are partially sunny upland sites in open deciduous woodlands and woodland borders along streams and roads. This aster occurs from Texas and Alabama north to Minnesota and Pennsylvania. In Arkansas, one of 21 native asters in the genus Symphyotrichum in the state, Drummond’s aster occurs throughout the Interior Highlands and Crowley’s Ridge along with several additional scattered counties. The genus name comes from Greek words relating to “a growing together” and “hair,” based on a misconception that pappus hairs occurred in a ring in the type species, New York aster (Symphyotrichum novi-belgii). The specific epithet and common name recognizes Thomas Drummond, a Scottish botanist, who, in the early 1830s, collected specimens in Texas. Other common names include blue wood aster and hairy heart-leaf aster.

Young plants have a half-dozen or so round to oval leaves up to 2 inches long in a loose rosette. Leaves have long petioles with a central depression and with stiff ascending edges. Margins are boldly serrated. Upper surfaces are medium green and lower surfaces are lighter green. Soft dense pubescence covers the undersides of leaves while pubescence on the upper sides and along petioles is less soft and less dense.

Older plants develop new basal growth in late fall that survives into spring when plants may have one or a dozen or more terete stems in a tight clump (cespitose). Basal leaves, broadly lanceolate, form a dense mass from which stems bolt. Stems, which may reach 3 to 4 feet tall, have numerous short (6 inches) to long (18 inches) branches in the upper half as well as lower insignificant axillary branching. Stems are spindly and erect, but may lean when supporting a large inflorescence. Stems are light green in spring, possibly with purplish shading, becoming yellow-green in fall. Basal and lower cauline leaves wither as stems mature. Dead, brown, woody-like stems persist into the next growing season.

Drummond's Aster - Symphyotrichum drummondiiPhoto 1: In mid-April, multiple leafy stems of Drummond’s aster bolt from a tight root clump. Plant in lower right foreground is false aloe (Manfreda virginica).

Alternate, long petioled cauline leaves may be spaced 3 inches apart lower on stems with spacing gradually decreasing to 1 inch at base of inflorescence. Largest leaves occur in the lower half of plants where leaves may be 4 inches long and 1+ inches wide. Lower leaves have cordate bases and acuminate (long tapering) apices while higher leaves, with similar apices, have bases that become more rounded. Petioles, to 2 inches long, have narrow wings extending from leaf blade to petiole base that enhance central grooves along the petioles. Petiole and blade mid-rib form a gentle continuous arch (viewed from side), while cordate bases of leaves rise above that arch. Leaf axils below the inflorecence often produce groups (fascicles) of two or three small (to ¾ inch long and 3/8 wide) oblong to elliptic leaves with short, winged petioles. While large leaves have well-spaced shallow serrations or crenulations, margins of small leaves tend to have hardly perceptible serrations. Leaves, medium green above and lighter green below, may become a golden green late in the growing season. Lower leaf surfaces are uniformly covered by short, dense and soft pubescence, while upper surfaces have short, stiffer and less dense pubescence. Lower surfaces feel smooth; upper surfaces are slightly rough. Venation is pinnate with veins on the upper side slightly depressed and those on underside slightly expressed. Leaves within the inflorescence become increasingly smaller and narrower, with those that subtend peduncles and pedicels becoming lance shaped.

Drummond's Aster - Symphyotrichum drummondiiPhoto 2: Short dense pubescence can be seen on underside of a leaf (lower center right) and along stem and petiole (upper center). Petiole and leaf mid-rib form a gentle arch.

Drummond's Aster - Symphyotrichum drummondiiPhoto 3: Display of large cauline leaves and small axillary leaves. Upper leaf surfaces shown to left and lower surfaces to right of spindly lower stem section. Petioles of these cauline leaves are winged, regardless of leaf size. Photo: mid-October.

In mid-summer, floral branching occurs in upper portion of stems with first flowers appearing about mid-September. Inflorescences consist of a few to numerous long (6 inches), straight, spreading yet upward-trending lateral branches in open-spike style or short (2 inches) branches in a more compact panicle style. Branches have small bract-like leaves spaced ¼ inch or so apart along their entire length with uppermost leaves subtending peduncles from one to 4 inches long. Peduncles are lined with overlapping to closely spaced 1/16 inch lanceolate, ascending bracts which continue to the short pedicels from which bracts transition directly into lanceolate, pointed phyllaries. Composite flower heads, to ½ inch wide, are borne on the pedicels at and near peduncle apices. Additional minor flowering may occur directly from axils of the large cauline leaves where single peduncles bear flower heads along their upper ends. Flowering occurs in late summer into mid-fall.

Drummond's Aster - Symphyotrichum drummondiiPhoto 4: Prior to appearance of flowers, peduncles and pedicels, covered with pointed ascending bracts, appear cedar-like. Photo: early September.

Drummond's Aster - Symphyotrichum drummondiiPhoto 5: Plant at full bloom with long branches that create an open-spike style of inflorescence, as compared to a plant with short branches that would have a panicle style inflorescence.

Drummond’s aster, as with all asters in the genus Symphyotrichum, has composite flower heads consisting of seed-producing pistillate (no stamens) ray florets that surround seed-producing perfect (stamens and pistil) disk florets. Heads have 10 to 15 ray florets and a smaller number of tightly clustered disk florets.

Ray florets have narrow, white to blue ligules with rounded to slightly notched tips and claw-like (narrowed) bases. Ligules, about ¼ inch long and 1/16 inch wide, are arranged irregularly and may overlap. Short styles are topped by long, bifurcated and widely spread stigmas. Disk florets, 1/10 inch long, are tubular, with corolla tubes topped by triangular lobes which close the tube in bud but point upward at anthesis. Corollas are initially cream-yellow color, but become reddish purplish shortly after opening. Five elongate anthers, not exserted, form an erect unit that encircles a tannish style. Styles become strongly exserted and stigmas divide but remain joined at their tips. Flower heads have a flat center (receptacle) held by an involucre composed of imbricated (overlapping), lanceolate, appressed and glabrous sepal-like phyllaries. Phyllaries may have a purple tip. Color differences along phyllaries may create a subtle diamond-shaped pattern. Phyllaries, in 4 or 5 series, transition directly into the lanceolate bracts that extend down the pedicel and onto the peduncle. Inferior ovaries are topped by bristly structures (pappus).

Drummond's Aster - Symphyotrichum drummondiiPhoto 6: Corollas of disk florets change from cream-yellow to reddish-purple as florets mature. Note similar appearance of appressed phyllaries and bracts. Photo: mid-October.

Drummond's Aster - Symphyotrichum drummondiiPhoto 7: A flower spike bearing heads at various stages of bloom. Note white bifurcated stigmas of pistillate ray florets (see floret at upper-right corner). Apices of phyllaries may be purple (see left-most flower heads).

Each ray and disk floret may produce a single brown achene (technically called a cypsela–a dry one-seeded, non-splitting fruit from an inferior ovary) with tufts of white hairs (pappus) encircling the top. Achenes, about 1/10 inch long, are oblong and ridged. They are dispersed by wind.

Another blue-flowered aster species of Arkansas that has disk flowers that change from yellow to purplish, and grows in similar habitats as Drummond’s aster, is blue wood aster or heart-leaf aster (Symphyotrichum cordifolium). S. cordifolium has leaf blades that have an overall heart-shape (not just the base) and long, unwinged petioles. Leaves of Drummond’s aster have shorter winged petioles.

Article and photographs by ANPS member Sid Vogelpohl

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