Know Your Natives – Woodland Phlox

Woodland phlox, blue phlox or wild sweet William (Phlox divaricata ssp. laphamii) of the Phlox (Polemoniaceae) family is the first phlox to bloom in the spring in Arkansas. The genus name is Greek for “flame,” in reference to many species of the genus with strongly colored corollas. The specific epithet, from the Latin, refers to the clonal “spreading” of the plant or possibly to the spreading branches of the inflorescence. The subspecies name honors Wisconsin scientist Increase A. Lapham.  The species occurs from Texas to South Dakota, thence east and south to the Atlantic and Gulf Coasts. In Arkansas, it occurs statewide.

Woodland phlox grows in rich, well-drained, mesic, sandy to rocky soils in deciduous woodlands, with full or partial shade. Plants also grow in more sunny sites that have dependable moisture, such as stream banks. With prevailing dry conditions, plants may lose leaves and go dormant. 

Stems and pedicels are covered with a dense short, soft, white pubescence, which lessens with time. New stems and pedicels tend to be purplish, becoming green with age. They emerge from shallow, uniformly-sized, slender white roots. There are two stem types.

One stem type produces the inflorescence, referred to herein as a “floral stem.” Floral stems grow to about 14 inches and bear short branches within the inflorescence. They emerge in early winter and die off after fruit matures.

A second stem type, referred to herein as a “clonal stem,” is initially erect, but becomes reclined with new apical growth. As the stems elongate, the older, lower leaves drop off. The leafless portion, surviving over a number of years, may be from an inch to several feet long. As this leafless portion becomes covered with duff, long, slender, white roots and stems emerge from the leafless leaf nodes. Over time, intertwined clonal stems may form mats of evergreen leafy stem apexes.

Photo 1: Floral stems appear in early winter with flowers reaching anthesis in March. Several broad-leafed clonal stems can be seen on the left side of photo.

Leaves of both stem types are similar in that they 1) are in opposite, widely spaced pairs set at 90 degrees to each other (decussate pairs), 2) have a medium green adaxial surface and a lighter green abaxial surface, 3) are sessile to clasping with bases that meet around the stems, 4) have scattered pubescence above and denser shorter pubescence below, and 5) have entire margins. Also for both stem types, pinnate leaf venation consists of a straight, skinny, sharply recessed midrib above and a strongly expressed midrib below, with off-set secondary veins that fade into obscure tertiary veins. The base of the leaf blade ascends from the stem, while the remainder of the blade is flattened toward sunlight with a gentle up-folding along the midrib.

Leaf shape of the two stem types is different. Floral stem leaves are ovate-lanceolate (to 2½ inches long and ½ inch wide) while clonal stem leaves are broadly oval to ovate (to 2 inches long and 1 inch wide).

Photo 2: Floral stems have more-elongate leaves than clonal stems. Note pubescence of leaves and calyxes.
Photo 3: In August, only clonal stems remain. Inset shows a clonal stem in December that has leafy current-year growth and 4 to 5 years of growth that has produced roots and stems at leaf nodes (leaves having dropped off).

The inflorescence, which terminates a floral stem, first appears as a tight spiky cluster of medium green, closed, pointed calyxes and a few small subtending leaves. With growth, this single cluster expands into several loose clusters: a terminal cluster and a couple of upper, axillary clusters. These several small clusters form a rounded (2 to 3 inch wide) inflorescence with 20 or more flowers. Stems and pedicels, purplish, have a dense, short, white pubescence. As corollas approach anthesis, extending well out of the calyxes, they have long slender tubular throats that abruptly widen distally into a shorter, twisted spindle of tightly overlapped corolla lobes.

At anthesis, corolla lobes spread to about one inch wide, with a “smooth” coloration of various shades of blue, lavender and blue-violet. A dark blue to purplish color at the throat entrance is enhanced by being outlined by a lighter shading. Interior and exterior of the throat are a similar dark color. Lobes, with a rounded to slightly peaked apex, are obovate (broader at apex and a wide taper to base) and slightly overlapped. Calyxes, covered with spiky, sticky pubescence, have short cupped bases that are rimmed by five very long, lanceolate lobes. All flowers of a plant bloom at about the same time with bloom period extending over two weeks.

Photo 4: Tightly wrapped corolla lobes unfurl to expose a dark throat. Note the beautiful pinwheel-like overlapping arrangement of the lobes when still in bud, as well as the long teeth of the calyxes and long pubescence of calyxes compared to that of stems and pedicels. Photo – mid March.
Photo 5: This young plant has many floral stems and several clonal stems (to the left and below).

Flowers have five stamens and a pistil, hidden within the corolla tube. Stamens are fused to the tube (rather than to the tip of the pedicel, i.e., the receptacle) and of varying lengths. They have white filaments supporting elongate anthers that produce bright yellow pollen. The style, set on a smooth green ovary, is pale green with a three-part spreading stigma. Ovary, style and stigma are short and about equal length. With fertilization, the ovary becomes a three-chambered, smooth, ovoid fruiting capsule that produces a few seeds. Capsule length is less than ⅛ inch.

Photo 6: Flowers have five adnate stamens of unequal length that bear elongate anthers. With calyx partially and corolla tube fully removed, the pistil, comprising ovary, style and stigmas, is revealed.

Woodland phlox is an ideal plant for shady natural areas, rock gardens and shade gardens that have fertile mesic soil. Its mass flowering in late winter is an early sign of winter’s imminent departure. Clonal colonies and newly seeded plants are not aggressive. With shallow clumping roots, sweet William can grow well with other native species. It may be eaten by deer and rabbits.

Other species of the genus that occur in Arkansas: 1) broad-leaf phlox (Phlox amplifolia), 2) sand phlox or cleft phlox (Phlox bifida – two subspecies), 3) annual phlox (Phlox drummondii), 4) smooth phlox (Phlox glaberrima), 5) garden phlox (Phlox paniculata), 6) downy phlox (Phlox pilosa – two subspecies), and 7) moss phlox (Phlox subulata).

Characteristics of woodland phlox that help separate it from these other species are its 1) broad leaves and sterile clonal stems, 2) hidden stamens, 3) broad corolla lobes with rounded to slightly peaked apexes, and 4) lack of a tap root.

Note: Phlox divaricata ssp. divaricata, another recognized subspecies (not known to occur in Arkansas), has very similar characteristics, except subspecies divaricata has apically notched corolla lobes. The range of subspecies divaricata partially overlaps that of subspecies laphamii, but subspecies divaricata primarily occurs farther east and north. Flower color of subspecies divaricata tends to be more pinkish.

Article and photographs by ANPS member Sid Vogelpohl

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Regulatory changes on the use of the chemical Dicamba in Arkansas

Dear ANPS Member,

The ANPS Board of Officers is carefully following the pending decision to change the Arkansas regulation on the use of the chemical dicamba.  This agricultural herbicide, designed to be used on genetically modified crops resistant to the chemical, has become a controversial issue among both farmers and the ecological communities in the state.
Many ANPS members, board members and our friends in Audubon Arkansas believe that the Arkansas Plant Board should not extend the use of this herbicide beyond April 15th of each year in Arkansas.  The argument is that the volatility of the chemical during the warmer months has a harmful side effect on non-resistant crops, honeybee nectar sources and native plants.  This warm weather use of dicamba could also seriously affect native plants and the native and non-native plant nectar sources for pollinators such as bumblebees, moths, butterflies, other insects, and hummingbirds. 

Yesterday, Gov. Hutchinson approved a thirty day public comment period before a final board meeting to vote on the issue.

Historically the ANPS has not taken a position on matters like this, preferring to instead inform the membership and the public regarding the science involved in any controversial agricultural or land use issue being considered by our local, state and federal government.  

We encourage each member of ANPS to take the time to educate themselves on this issue and then make an individual decision on whether and how to support or oppose the change to the regulation on use of dicamba in Arkansas.  

Both the Governor and the State Plant Board welcome comments from the public.  The 30 day comment period will begin in the next few days. 

Please take a moment to look at the links below for more information. 

Donna Hanke
President, ANPS

Modern Farmer-What is dicamba?

Arkansas Outdoor Country article on the dilemma for Arkansas farmers
Audubon Arkansas Urges Arkansans to Petition the Governor
Arkansas State Plant Board-Dicamba Issue
Contact Information for Arkansas State Plant Board (phone, email, address)
Contact Information for Governor Hutchinson
Governor Asa Hutchinson, State Capitol Room 250, 500 Woodlane Ave., Little Rock, AR 72201   (501) 682-2345
New Dicamba Restrictions Guidelines

AR Plant Board Approves Draft Regulation for 2019 Dicamba Use

Posted in Know Your Natives

Know Your Natives – Woolly Lip Fern

Woolly lip fern (Cheilanthes tomentosa*) of the Brake Fern (Pteridaceae) family, is an evergreen fern that becomes brown and shriveled during drought but revives with renewed moisture. The genus name combines Greek words for “lip” (cheilos) and “flower” (anthos), in reference to the location of the sori or “fruit dots” (see below). The specific epithet describes the plant’s pubescence: tomentose, from the Latin, meaning “with thickly matted hairs”. The common name “lip fern” refers to the smoothly under-turned margins of the pinnae (leaflets). Cheilanthes tomentosa is also called “resurrection fern”, a name that applies to several different species. In the U.S., woolly lip fern occurs across the southern states from Arizona to Virginia, as well as in southeastern Kansas and southern Missouri. It is absent from Louisiana, Mississippi and Florida. In Arkansas, it occurs in rocky elevated areas of the Interior Highlands of the northwestern half of the state. Its preferred habitat is dry soils on sunny rocky ledges and slopes, especially in crevices.

Photo 1: Woolly lipfern grows well in sunny rocky area. Photo – May 28.
Photo 1: Woolly lip fern grows well in sunny, rocky areas. Photo May 28.
Photo 2: The fern becomes dehydrated during dry conditions, but revives with renewed moisture. Photo – September 15.
Photo 2: The fern becomes dehydrated during dry conditions, but revives with renewed moisture. Photo September 15.

Woolly lip fern, a clumping fern with an erect rootstock, has a dense tangle of thin, wiry, fibrous roots. The rootstock supports an expanding thick cluster of intermixed living and dead leaves, in the ferns, generally known as fronds. Rootstocks of several individual plants may grow together. New silvery fronds, with down-folded apexes, appear in spring or during summer into fall in response to renewed moisture and even during winter with favorable temperatures. Mature fronds are a bluish to medium green on the adaxial side and a tannish light green on the abaxial side. They ascend from a central point in small plants or randomly in larger plants. In outline, fronds have a linear to lanceolate shape. Mature fronds survive winter temperatures while new fronds may freeze. Fronds remain alive for a year, the older ones dying out in late fall into winter. Pinnae (leaflets) of dying fronds, as well as those that become dry due to drought, curl inward from their sides and apexes. Dead fronds remain attached to the rootstock for years as they gradually disintegrate.

Photo 3: New, mature and dead fronds intermix to form a dense clump. New fronds emerge when moisture is available and temperatures are not freezing. Photo – December 14.
Photo 3: New, mature and dead fronds intermix to form a dense clump. New fronds emerge when moisture is available and temperatures are above freezing. Photo December 14.

Sori, the clusters of spore-producing sporangia, are borne on the abaxial (under) surface of fertile fronds (see below). The adaxial (upper) surfaces of fertile and infertile fronds are indistinguishable. Fronds are generally 8 inches to 16 inches long and 2 to 3 inches wide. Of the total frond length, the rachis (pinna-bearing midrib) tends to be about three times longer than the stipe (frond stalk). Fronds have 40 or so pinnae that are generally alternately arranged along the rachis; however, lower pinnae may be in sub-opposite or even opposite pairs. The largest pinnae tend to be near the middle of the rachis. Spacing between pinnae decreases distally until pinnae near the frond apex are in contact with each other.

Photo 4: Two infertile fronds are to the left (adaxial and abaxial sides shown). Two fertile fronds are to the right (adaxial and abaxial sides shown). Photo – December 14.
Photo 4: Two infertile fronds are to the left (adaxial and abaxial sides shown). Two fertile fronds are to the right (adaxial and abaxial sides shown). Photo December 14.

Dense white pubescence on new fronds gives them a silvery appearance. The pubescence extends around stipe and rachis, petiolules (stalks of pinnae) and costae (midribs of pinnae), as well as over both upper and lower pinna surfaces, though much denser abaxially. As fronds age, pubescence becomes light brown and thinner. Pubescence along the slender, stiff, round stipe and rachis may be scrapped off to expose a dark purple surface.

Woolly lip fern is a thrice-cut fern. Pinnae are more or less flat and tilted toward sunlight. In outline, they are ovate-lanceolate, broadest toward the middle and gradually narrowing to a rounded distal end. Pinna margins are incised with a dozen or so pairs of slightly off-set, apically rounded pinnules (sub-leaflets). The longer pinnules are further cut proximally into apically rounded, oval lobes. Margins of pinnae and pinnules curve from adaxial to abaxial surface to form a narrow continuous lip along the abaxial side.

Photo 5: Display shows abaxial side of an infertile frond (left) and fertile frond (right). In this December 7th photo, outlines of the developing sori can be seen on the right frond. Note the tan pubescence that extends from the rachis onto the costae and pinnae.
Photo 5: Abaxial surfaces of an infertile frond (left) and fertile frond (right). In this December 7th photo, outlines of the developing sori can be seen on the fertile frond. Note the tan pubescence that extends from the rachis onto the costae and pinnae.

Sori, in bumpy linear strips, are adjacent to and slightly covered by the marginal lip. A true indusium (sorus cover) is lacking. Mature sori are smooth and black. Spores, dispersed by breezes, are released in summer.

With spores having been dispersed, the above-ground “diploid sporophyte phase” of a fern’s life cycle (referred to as “alternation of generations”) concludes. In the soil, spores germinate to produce a prothallus, the “haploid gametophyte phase”. For most ferns, the prothallus produces mobile sperm gametes and attached egg gametes, allowing fertilization of the egg and development of a new diploid sporophyte plant. However, woolly lip fern is apogamous–zygotes form without fertilization.

Photo 6: In this May 21st photo, sori are well developed. Note lipped margins and change of pubescence from tan to white. The dense pubescence hides the purple rachis.
Photo 6: In this May 21st photo, sori are well developed. Note lipped margins and change of pubescence from tan to white. The dense pubescence hides the purple rachis.

In a garden environment, woolly lip fern would add texture and character throughout the year. It is one of few ferns that grows well in sunny, dry, rocky sites–a nice selection for rock gardens or for crevices of a rock wall. In an especially favorable site, numerous new plants may appear. Should older plants become unattractive, due to retention of dead fronds, clumps not in crevices are easy to remove. Woolly lip fern survives drought and is not favored by deer.

Four other lip ferns occur in Arkansas; namely, Alabama lip fern (Cheilanthes alabamensis), Eaton’s lip fern (Cheilanthes eatonii), slender lip fern (Cheilanthes feei), and hairy lip fern (Cheilanthes lanosa). Woolly and hairy lip ferns are the two most common lip ferns in the state. Hairy lip fern is significantly smaller than woolly lip fern, and it has less dense pubescence. Additionally, to distinguish woolly lip fern from the other lip ferns, woolly lip fern has 1) a coarser appearance, 2) an erect clumping growth habit, 3) tomentose stalks and pinnae, and 4) alternate pinnae.

Photo 7: Hairy lipfern (lower in photo), smaller than woolly lipfern, has fewer more widely spaced pinnae. In this photo of December 14th, pubescence had been mostly worn away.
Photo 7: Hairy lip fern (lower in photo), smaller than woolly lip fern, has fewer more widely spaced pinnae. In this photo of December 14th, pubescence had been mostly worn away.

* Some authorities classify woolly lip fern as Myriopteris tomentosa.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Sparkleberry

Sparkleberry (Vaccinium arboreum) of the Heath (Ericaceae) family is a blueberry that adds persistent color to the fall-foliage palette. The genus name is ancient, but of no clear meaning–possibly from the Latin vaccinus, “of cows”. The specific epithet is from the Latin, meaning “tree-like”. Sparkleberry occurs from Texas to Kansas east to the Atlantic and Gulf Coasts. In Arkansas, the plant occurs statewide except for especially low and wet areas. The common name “sparkleberry” refers to the shiny fruit. Other common names include farkleberry, tree huckleberry and winter huckleberry. The origin of “farkleberry” is unknown, but may be a misspelling of “sparkleberry”.

Photo 1: Sparkleberry can be tree-like. Its fall color is one of its aesthetic attributes. Photo November 16.

Sparkleberry occurs in a wide variety of well-drained habitats: wooded mountainous areas, rocky outcrops, stream banks and open fields. Preferred sites are dry, sandy to rocky soils overlying sandstone (i.e., preferring acidic soils like most blueberries). More robust plants, with the best fruit production, occur in sunny areas.

Sparkleberry is a shrub or small tree with single or multiple crooked to gnarly trunks and branches, typically growing from 5 to 10 feet tall, but occasionally reaching 20+ feet. Main stems of younger plants and trunks of older plants grow from a compact base. The crown may be leggy, spreading or arching, depending on plant age and site characteristics. All trunks, branches and twigs that are older than the current growing season are woody and rigid. Overall color of trunks and branches is a light to medium gray with reddish areas. Over the years, lower portions of the trunks lose their smaller branches. Finely textured bark may split into narrow exfoliating strips. The shrub is slow-growing, however vertical branches may grow 2 to 4 feet in a single season, as they reach into open areas of the crown.

Photo 2: Trunks of older plants become gnarly. Thin bark exfoliates near the plant’s base to reveal reddish new bark. Photo December 12.

New spring growth is from tips of previous year’s branches, producing a myriad of short, slender, straight, ascending twigs that become a light to dark gray as they “harden” over the growing season. New leaves quickly change from reddish to green. Fruit-bearing racemes (see below), which may terminate twigs, ultimately drop off.

Twigs bear alternate, simple, oval to elliptical leaves, some shrubs dominated by oval leaves, others by elliptical. Mature leaves have a shiny, medium to dark green adaxial (upper) surface and duller, lighter green abaxial (lower) surface. Leaves range from 1 to 3 inches long and ½ to 1¼ inches wide, along with short petioles (1/16 to 1/8 inch). The leathery (coriaceous) leaves typically have rounded to abruptly acute (mucronate) apexes with similarly shaped bases; however, larger leaves may have acuminate (gradually tapering) apexes and wedge-shaped bases. Margins are typically entire, but some leaves may have very short teeth. Leaf pubescence is absent except for short pubescence along principal abaxial veins. In mid-fall, leaves change to various shades of red to purple and, depending on temperatures and wind, may sparingly persist well into winter months.

Venation is pinnate, with adaxial veins being slightly suppressed and abaxial veins being slightly expressed. Five to seven secondary veins angle from the midrib toward the leaf apex, drifting toward the leaf margin, but become “lost” in the tangle of loopy tertiary veins. Elsewhere, tertiary veins connect with secondary veins to form a loopy-reticulated pattern. 

Inflorescences, in late April into May, consist of flowers on twigs of the current season. Flowers are axillary or in terminal racemes, each raceme being a direct extension of the twig. Floral bracts become more or less reduced distally. To 2½ inches long, racemes bear up to a dozen dangling flowers, arranged alternately along the finely pubescent reddish rachis. Flowers are on slender light green pedicels, ½ to ¾ inch long.

At bud-stage, the pale green flower buds have five prominent ribs with sunken areas in between, marking the center-lines of 5 sepals. With anthesis, seemingly inflated white (to slightly pink) corolla tubes become broadly bowl-shaped, narrowing at the tip into 5 short, reflexed lobes that create a small down-facing opening. The corolla is set in a short, pale green, bell-shaped (campanulate) glabrous calyx with 5 short-triangular lobes that press against the corolla’s base. Blooms extend sequentially from lowermost axillary flowers to flowers at raceme tips. Flowers are fragrant.

Photo 3: This shrub has oval coriaceous leaves with entire (uncut) margins. Several leaves have mucronate (tipped) apexes. Note loopy-reticulated vein pattern. Photo May 2.

Flowers have stamens, which remain enclosed within the corolla, and a stout, pale green, exserted, post-like style. Each stamen has a stout white filament capped with a brownish orange, lobed anther that is, in turn, tipped with brownish yellow appendages, of which one is wide and thin and the other round and pointed. These appendages are longer than the pollen-bearing portion of the anther itself. The style terminates with a flat stigmatic surface.

Photo 4: This twig has axillary flowers and flowers along a terminal raceme. Styles are exserted from the corolla. Inset: calyx with pistil (mostly style visible) and stamens with appendage-tipped anthers. Photo May 26.

Shiny fruits (berries) develop over summer, changing from a medium green to reddish and then black in September. Dangling berries, persisting well into winter, are ¼ to ⅜ inch in diameter, the size varying by shrub. Berries have a varying number of developed and undeveloped gritty seeds. Fully developed seeds, about a 1/16 inch long, are irregularly rounded. Early in the season, berries are juicy, with a not-unpleasant but often insipid flavor, the least tasty of our state’s blueberries. Later in season, berries become dry.

Photo 5: Shiny dangling spherical berries change from green to black. Axillary berries and berries in racemes can be seen. Photo September 25.
Photo 6: Display of fruited twigs, as seen from backside. Stubby calyx scars can be seen at top of fruits. Note seed at right. Scale: squares are ¼ inch. Photo November 14.

Sparkleberry, which may be difficult to establish in a garden, can be a highly desirable shrub for a garden or natural area. It has year-round positive attributes with its architectural branches and trunks, fragrant interesting flowers, nicely colored fall leaves, and black berries.

Sparkleberry is a nectar source for butterflies and a host plant for both Henry’s elfin butterfly (Callophrys henrici) and the striped hairstreak (Satyrium liparops). Persistent berries are a dependable food for birds and small mammals well into winter months. Established plants are drought tolerant. In some areas, plants may be browsed by deer.

Other species in the genus that occur in Arkansas are 1) Mayberry (Vaccinium elliottii), 2) High-bush blueberry (Vaccinium fuscatum), 3) Common blueberry (Vaccinium virgatum), 4) Low-bush blueberry (Vaccinium pallidum), and 5) Deerberry (Vaccinium stamineum).  Characteristics of Vaccinium arboreum that distinguish it from the other five species include large plant size, rigid branches and twigs, bowl-shaped corolla tube, late time of flowering, partial retention of leaves into winter, and persistence of fruit into winter.


Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Arrowhead

Arrowhead (Sagittaria platyphylla) of the Water Plantain (Alismataceae) family is an aquatic perennial of shores and marshes. It is one of eight Sagittaria species found in Arkansas that have “arrowhead” as their common name (see below). The genus name is from the Latin sagitta, an arrow, for the sagittate (arrow-shaped) leaves of some other species in the genus. The specific epithet is Greek for “flat-leaved.” This particular species of arrowhead occurs from Texas to Kansas, east to Virginia and south to the Atlantic and Gulf Coasts. In Arkansas, it is recorded pretty much statewide. Other common names include delta arrowhead, delta duck-potato, and broad-leaf arrowhead.

Arrowhead is an aquatic monocot found on the banks and shallow waters of marshes, swamps, sloughs, and ponds where its roots are either in mud or underwater. Plants do not occur where flow rates are high or water depth exceeds several feet. Soils may be mucky to sandy. The bulb-like corm bears shallow fibrous radiating roots as well as shallow slender underground stolons that extend outward a foot or more. New plants are established at tips of stolons and from seed. Plants can spread aggressively. In slow-moving water, sediments become trapped so that water depth becomes more shallow. Established plants may totally disappear during dry conditions but reappear as wet conditions return.

This arrowhead has three glabrous (hairless) leaf forms that are produced from the basal stem or caudex. Early in the growing season, submerged radiating strap-like leaves (a foot or more long and an inch wide), without petioles, are produced. With warming conditions, plants produce erect narrow strap-like emergent leaves (also without petioles) that extend a foot or more above the water surface, as if testing water depth. In the summer, broad emergent leaves are held well above the water surface on long petioles. If the water level rises above emergent leaves, these leaves tend to die-off.

Arrowhead - Sagittaria platyphylla
Photo 1: Early strap-like leaves are submergent. Several later-growing emergent strap-like leaves can be seen to the right. Photo May 17.
Arrowhead - Sagittaria platyphylla
Photo 2: Strap-like emergent leaves become dominant later in spring as submergent leaves decay. Plant in near foreground is wool-grass bulrush (Scirpus cyperinus). Photo April 18.

The broad summer leaves have ovate to elliptical blades to 15 inches long and 4 inches wide with petioles to about 15 inches long. Some smaller emergent leaves may have lanceolate blades. Upper and lower sides of leaf blades, along with the petioles, are a medium green, with the lower side duller. Leaf blades have entire, thinly recurved margins, a rounded apex terminating in a small acute tip, and broad rounded bases (although occasionally with slightly flared bases). Midribs are a lighter green with abaxial midrib being strongly keeled while adaxial midrib is weakly keeled or suppressed. Widely spaced secondary veins are arcuate and trend toward the blade apex. Narrowly spaced tertiary parallel pinnate veins extend, at about 50 degrees off midrib, to leaf margins, seemingly crossing secondary veins unimpeded. The spongy petioles are triangular in cross-section, with one angle being the continuation of the abaxial midrib and the two lateral angles extending downward from the junction of the leaf blade with the petiole. The two lateral angles become increasingly “flappy” from the lower portion of the petiole down to the caudex, where they channel an emerging younger leaf.

Arrowhead - Sagittaria platyphylla
Photo 3: Emergent summer-time leaves have large blades and long triangular in cross-section petioles. Leaf bases are usually rounded, the apexes tipped. Note venation shown by large leaf. Photo July 17.

Flowers are unisexual. Inflorescences, from spring into fall, develop alongside the leaf bases. Flowers are borne along the inflorescence axis in whorls of three, with pistillate and staminate flowers typically in separate whorls, and the pistillate lowermost. The inflorescence is significantly shorter than the broad emergent leaves. Each floral whorl is subtended by three broad, striated, medium green, connate (joined at their bases) bracts which, at first, totally cover developing whorls, but dry into tissue-thin persistent brown flaps as flowers reach anthesis.

Male and female flowers (to ¾ inch wide), with three broadly rounded, green, cupped, persistent sepals (to ⅓ inch long) and three broadly rounded, clawed, white petals (to ⅝ inch long), are on ascending pedicels (from ¼ to 2 inches long) at time of bloom. Pistillate flowers, reaching anthesis before staminate flowers, have a prominent, slightly flattened, yellowish-green, globoid cluster of numerous pistils tipped with short styles, the tips angled toward the top of the cluster. Staminate flowers, on more slender pedicels, have multiple stamens with light colored filaments and bright yellow, two-part anthers. The pedicels of pistillate flowers strengthen and recurve downward as fruits develop, whereas those of staminate flowers remain ascending and fade after pollen release.

Arrowhead - Sagittaria platyphylla
Photo 4: Two lowermost whorls of both stems are pistillate. Pedicels of pistillate flowers recurve downward as fruits develop. Open flowers on the higher stem are staminate–note their more slender pedicels. Photo September 26.
Arrowhead - Sagittaria platyphylla
Photo 5: Staminate flowers have two-lobed yellow anthers. Higher-positioned immature whorls, at center of photo, also appear to be staminate. Photo June 7.

Fertilized flowers produce a solid globoid cluster (to ½ inch across) of achenes. Achenes have small beaks (remnants of styles) that give the exterior of the cluster a roughened texture. Mature, flattened, 1/10-inch-long achenes have a bent-oblong shape, with the beak off-set to one side and with narrow lateral wings. The buoyant achenes are easily dispersed by water movement. They produce grass-like seedlings.

Arrowhead - Sagittaria platyphylla
Photo 6: Fruiting heads consist of numerous achenes. Achene beaks give heads a roughened texture. Photo November 17.

For a water garden or boggy area, arrowhead may be a suitable addition. (Its aggressive nature should be understood before its introduction.) The plant propagates by seeds, corms, stolons and parts of stolons. A dense growth of arrowhead can provide welcome habitat for frogs, turtles and many insects and spiders. Arrowhead can survive periods of dry soil.

Along with Sagittaria platyphylla, the subject of this article, Arkansas has several other native species of arrowhead: Sagittaria australis, Sagittaria brevirostra, Sagittaria graminea (grass-leaf arrowhead), Sagittaria latifolia (duck-potato), Sagittaria montevidensis subsp. calycina, Sagittaria papillosa, and Sagittaria rigida (stiff-leaf arrowhead). Of these, S. graminea, S. papillosa, and S. rigida have leaf shapes that are similar to S. platyphylla. Sagittaria platyphylla can be distinguished from each of them by one or more of the following characters: 1) floral stems that are not branched, 2) floral stems that are shorter than the broad-emergent leaves, 3) broad-emergent leaves that have triangular petioles, 4) pistillate flowers and fruits that are not sessile, 5) fruiting pedicels that are recurved, and 6) bracts and sepals lacking papillae (short, rounded bumps).

Three other native species in other genera may be confused with Sagittaria platyphylla, namely, creeping burrhead (Echinodorus cordifolius subsp. cordifolius), water plantain (Alisma subcordatum), and pickerel weed (Pontederia cordata, in a different, unrelated family). Sagittaria platyphylla can be distinguished from those species by its triangular stems that support three-whorled white flowers below the large emergent leaves.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Wreath Goldenrod

Wreath goldenrod (Solidago caesia) of the Aster or Sunflower (Asteraceae) family is one of the smaller goldenrods that occur in Arkansas. In the U.S., it is found from Texas to Wisconsin and thence east to the Atlantic and Gulf Coasts. In Arkansas, it occurs across the state except for portions of the Mississippi Alluvial Plain and West Gulf Coastal Plain. The genus name is from Latin for “to make whole” or “to heal” in reference to purported health benefits derived from some species of the genus. The specific epithet, also from Latin, for “slate blue” in reference to stem color. Other common names include blue-stem goldenrod and woodland goldenrod.

Wreath goldenrod, a plant of mesic soils in upland deciduous woods, well-drained lowlands and bluff areas, is a herbaceous perennial that propagates by seed and rhizomes. Plants that have a half-dozen or more compact-growing stems are probably growing from a caudex supported by many long, slender, white, radiating, rope-like roots. While single-stem plants are probably growing from a rhizome’s tip or from node junctions along its length. The white, near-surface, stubby rhizomes are slow growing so that non-aggressive colonies may develop.

Stems, a light green when young, typically become bluish to purplish (on the sunny side) with an overcast of whitish bloom (i.e., a thin, waxy coat). The smooth, slender, terete stems, reaching 3 feet long, are ascending and arching, but frequently stems become reclined. Stems typically have a half-dozen or so axillary lateral branches mid-stem, well below the tip. Lateral stems, with widely varying length to about 1 foot long, have the same appearance as primary stems. The lower portions of primary stems tend to be straight, while distally the more slender portions are slightly zigzagged. Lateral stems tend to be slightly zigzagged their entire length. Individual stems that have lateral stems appear rather “skeletal” due to the spacing of the rather sparsely leafed lateral stems. All stems are mostly glabrous (hairless).

Wreath goldenrod - Solidago caesia
Photo 1: Current-year stems grow from tips of rhizomes as new rhizomes emerge along their length. Stub of a previous-year stem can be seen at lower center. Photo October 24.
Wreath goldenrod - Solidago caesia
Photo 2: Leaves of springtime stems have wide serrations. Minor marginal pubescence can be seen on lower portion of several leaves. Photo March 5.

The alternate leaves of wreath goldenrod, randomly arranged around the stems, are dark green adaxially (above) and a lighter green abaxially (below). Stem (cauline) leaves vary from broadly lanceolate below, to lanceolate at mid-stem, to narrowly lanceolate distally. They measure up to 5 inches long and ¾ inch wide, become gradually smaller toward the apex and even minute along lateral branches within the inflorescence (see below). Cauline leaves gradually taper to an acuminate tip and a sessile or nearly sessile base. Most leaf margins are serrated, with teeth of basal leaves wider and less pointed and those of cauline leaves increasingly acute and sharply pointed. Uppermost small cauline leaves (½ inch long and ⅛ inch wide and smaller) may be entire. Leaves are smooth and nearly glabrous, with minor marginal pubescence at the base. All leaves in the upper portion of the plant subtend a lateral stem or inflorescence (see below). Basal leaves drop off as the plant approaches flowering, and lower cauline leaves, if dry conditions occur, drop off as well during flowering.

Wreath goldenrod - Solidago caesia
Photo 3: This plant has a dozen stems growing from a central caudex. Photo March 26.

Venation is pinnate. Veins of the adaxial surface are the same color as the leaf blade while, on the abaxial surface, the midrib and secondary veins are a light green. The midrib of the adaxial surface is suppressed while secondary veins may be slightly suppressed. Tertiary veins of upper surface are obscure while tertiary veins of lower surface are a dark green color such that a reticulated pattern is easily seen.

The inflorescence of wreath goldenrod, appearing for about a month in mid-fall, consists of small terminal and axillary clusters of composite flower heads. Flower heads reach anthesis from distal ends of stems, progressing downward. Clusters consist of 2 to 9 loosely arranged flower heads in short racemes. The number of flower heads in clusters generally decreases from stem apex, downward. All flower heads in a cluster reach anthesis at the same time and a fair number of clusters along a stem blooms at the same time, thus producing an arching wreath-like appearance. In cases where racemes appear to be especially long, one is actually seeing a very short lateral stem with tiny leaves, with each leaf subtending a flower head or two. Flower heads, drawn to sunlight, become secund (arranged along one side).

Wreath goldenrod - Solidago caesia
Photo 4: Arching stems often recline. Flower clusters become oriented toward sunlight. Sunny sides of stems become bluish to purplish with age. Photo October 15.

Clusters are composed of up to ten or so tiny, bright yellow, loosely arranged composite flower heads. About ¼ inch long (including peduncle), heads comprise three to four pistillate (no stamens) ray florets surrounding up to eight or so perfect (stamens and pistils) disk florets. Ray florets have broadly oblong ligules (the flat, strap-shaped, laterally extended part of a ray flower), with several pleats and an apical notch, as well as slender styles with pointy-tipped, bifurcated stigmas. Disk florets are tubular with acutely triangular flaring lobes, and five stamens with short filaments and anthers, fused into a ring, that clasp the developing slender style. As the style emerges from the ring of anthers, it pushes out and exposes their pollen, to be carried away by pollinating insects. Anthers then wither, becoming white. Once fully exserted, the pair of linear stigmatic surfaces divides and becomes receptive to pollen, typically from other flowers–and most productively, from flower heads on other plants. (There is, nevertheless, much self-pollination in the sunflower family.)

Wreath goldenrod - Solidago caesia
Photo 5: “Cluster” at left is composed of flower heads subtended by tiny leaves. Orange arrow indicates flared corolla lobes of a disk floret. Red arrow indicates style of a ray floret. Lavender arrow indicates anthers of a disk floret. White arrow indicates emerging style of a disk floret surrounded by ring of shrunken, whitened anthers. Photo October 17.

Wreath goldenrod flower heads are set in cup-like involucres composed of spirally arranged, tightly imbricated, oblong bracts (phyllaries). Heads have very short peduncles attached to short rachises so that racemes have a cluster-like appearance. Phyllaries transition below to tiny pedunculate bracts.

Wreath goldenrod - Solidago caesia
Photo 6: Involucres are composed of elongate, imbricated phyllaries that transition into bracts along peduncles. Note dark green tertiary venation of lower side of leaves and marginal pubescence at leaf bases. Photo October 17.

Fertilized florets produce flattened, 1/16-inch-long, minutely pubescent, elongate achenes (often termed cypselae in this family–single seeded, indehiscent, nutlet-like fruits), each topped with a pappus of silvery hairs. Dispersal is by wind.

This fall-blooming goldenrod species would work well in an open woodland setting that has mesic soil. Among the goldenrods, it is a more dainty species with smooth leaves and stems. Bright yellow clusters of flower heads are showy and the plant’s open structure is attractive. It is not aggressive. As with all goldenrods, wreath goldenrod attracts a variety of small insects and butterflies. Fall allergies, blamed on goldenrods, are primarily caused by ragweeds (Ambrosia spp.), wind-pollinated members of the same Sunflower family.

Wreath goldenrod is one of 28 species of goldenrods (some with additional subspecies or varieties) known to occur in Arkansas, of which two other species have somewhat similar flowering characteristics: zigzag goldenrod (Solidago flexicaulis) and Ouachita goldenrod (Solidago ouachitensis), both of rather limited occurrence in the state. Zigzag goldenrod can be distinguished by its significantly wider to oval petiolate, heavily serrated leaves and its non-glaucous green zigzag stems. Ouachita goldenrod, quite similar to wreath goldenrod and occurring only on north-facing slopes of the Ouachita Mountains, can be distinguished by its larger leaves on unbranched, more upright stems, non-secund flower clusters, and composite flower heads each with only one ray floret.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Obedient Plant

Obedient plant (Physostegia virginiana*) of the Mint (Lamiaceae) family is an attractive plant with showy late summer to early fall flowers. The genus name is from Greek words for “bladder” and “cover” in reference to the inflated calyx that covers maturing fruit. The specific epithet refers to the type locality, Virginia, the provenance of the specimen originally described by Linnaeus. This species occurs from Texas to North Dakota, thence eastward to the Atlantic and Gulf coasts, along with scattered (and perhaps introduced?) occurrences in New Mexico, Utah and Montana. In Arkansas, obedient plant occurs throughout much of the Interior Highlands of the Ozarks, River Valley and Ouachitas, along with scattered occurrences on Crowley’s Ridge and several south-central Coastal Plain counties. The common name “obedient plant” refers to the plant’s flowers obediently remaining to one side when pushed. Another common name is false dragonhead, from similarity to species of Dracocephalum (not found in Arkansas). Obedient plant occurs in sunny prairies, glades and partially sunny woodland openings, in moist to wet, fairly well drained, fertile soils.

Obedient Plant - Physostegia virginiana
Photo 1: Established plants begin to produce basal leaves in mid-winter. Photo – February 20.

Obedient plant is a glabrous (hairless) herbaceous perennial with radiating, shallow, whitish roots and many segmented rhizomes (in some forms*). Rhizomes terminate in a bud or two that will produce clonal stems the following spring. Shiny, dark green, stout stems, to 3 or more feet tall, are four sided with prominently raised, rounded corners. Decussate (alternating at 90 degree angles) leaves and branches, originating between the corners, are typically in matched pairs. Between leaf and branch pairs, stems appear segmented. Segments may be up to 1½ inches long lower on the stem and to ½ inch long higher up. Each stem segment is straight and equidimensional except for a short, enlarged, lighter green portion immediately below the next higher leaf or branch pair. Plants in less sunny areas may have many branches while those in less sunny sites or less fertile sites may be unbranched. The stout stems are erect and tough, but the entire plant may recline under weight of the inflorescence. With drying soils, lower leaves may drop, while flowering continues.

Obedient Plant - Physostegia virginiana
Photo 2: This pair of stems was produced by one rhizome (extending off to the lower left). Current-year rhizomes and rhizome buds can be seen along with a vegetative bud (between the stems). Rhizome roots emerge at lines of segmentation (nodes). Stem bases are ¼ inch across. Photo Sept 29.

Leaves, dark green above and light green below, are lanceolate with very gradual tapers from mid-leaf to the acuminate apexes and sessile bases. Leaves of large plants tend to be broadly lanceolate (to oblanceolate) to 5 inches long and 1 inch wide, while leaves of smaller plants are narrower. Leaf margins along the distal half of leaf have sharp, well-spaced serrations with tiny prickle-like tips, while serrations lower on leaf gradually reduce in size toward the stem. Leaf axils that are not subtending a branch or floral spike have rudimentary buds that can break dormancy if a distal portion of the plant is broken off.

Mature stem leaves are pinnately veined, with secondary veins unnoticeable on the upper side and slightly noticeable below. The light green upper midvein is channeled. The lower midvein is whitish green and strongly expressed. Secondary veins arch off the midvein and become parallel to the margins before fading away.

Obedient Plant - Physostegia virginiana
Photo 3: In this sunny site, the plant has many branches, each of which will produce one or more terminal floral spikes. Photo Jun 16.

Floral spikes with sessile flowers terminate the main and secondary branches and also grow directly from leaf axils. Blooming occurs for a month or more from late summer into early fall. Terminal spikes tend to be straight while lateral spikes curve upward. Lanceolate, decussate bracts, with entire margins, are widely spaced along the spike below and become tighter above. Lowermost bracts may subtend rudimentary buds while bracts along most of the spike subtend individual flowers. Bracts, at anthesis, are about half as long as calyxes (see below). Flowers are sessile (no pedicels). Terminal spikes may be 8 inches long with as many as 100 flowers, while lateral spikes are shorter with correspondingly fewer flowers. Flowers on the main stem and lateral branches reach anthesis at the same time, with flowering proceeding along the spike from base to apex. Individual corollas are open for several days and then drop from the receptacle, leaving behind the calyx and developing fruit.

Elongate, round-tipped buds open into puffy, light pink to lavender (sometime white) corollas that are up to ½ inch wide and 1¼ inches long. Corollas have a constricted, laterally flattened base set within a relatively small (to ¼ inch long and ⅛ inch wide), conical, 5-lobed calyx. From their constricted base, corollas abruptly flare into a broad, puffy tube that narrows slightly at the throat’s broad opening. Corollas have an arching “top-rib” along the proximal two-thirds, which strengthens the rather flimsy structure and provides for attachment of stamens (see below). The throat opening has a 3/8-inch-long projecting, slightly hooded rounded upper lip and a half-as-wide recurved lower lip with two small lateral lobes and a broader central lobe. Flower color is more intense in the areas of the lobes and along the top-rib while fading elsewhere, including the throat which is marked with a splatter of dark purplish spots. At anthesis, the length of the calyx is longer than the subtending bracts.

Obedient Plant - Physostegia virginiana
Photo 4: Anthesis proceeds from spike base to spike apex. Note the relative length of bracts and calyxes along the spike. (A green lynx spider [Peucetia sp.] can be seen at the base of the spike. It is a hunting spider, often preying on flower-visiting insects.)

Flowers have four straight, slender stamens and a straight,  slender style. Stamens are adnate (attached) to the underside of the corolla’s top-rib (see above) with a side-by-side pair positioned to either side of a central style that is held against the top of the throat by the stamens. Anthers dangle just below the outer edge of the upper lip with a divided (bifurcated) stigma in between and slightly farther out. The two-lobed anthers, when releasing pollen, have a circular appearance (similar to a horse’s hoof). Filaments have soft shaggy hairs (villous) on their upper portion. With fertilization, a flower produces four dull brown, smooth 1-seeded nutlets with rounded “sides” and two angled sides. Nutlets, less than ⅛-inch long, are dispersed by gravity.

Obedient Plant - Physostegia virginiana
Photo 5: Flowers have a bifurcated stigma with a longer upper portion that angles up while the lower portion angles sharply down. Note the two-lobed anthers and villous filaments.
Obedient Plant - Physostegia virginiana
Photo 6: Lower flowers have dropped off as upper flowers bloom. A bumblebee fits snugly into the throat, so that there is an excellent chance that pollen will be deposited on its back. The style connects to a tiny 4-lobed ovary deep within the calyx.

Obedient plant is an attractive wildflower, ideal for a sunny to partially shady garden or natural area with moist to mesic soil. However, in a preferred habitat, this plant can spread aggressively from rhizomes. Plants may need staking when in bloom to remain erect and seeded spikes may need to be removed to better control plant spread. The very attractive flowers persist for a month or more in late summer into early fall. It is favored by hummingbirds, bumble bees and carpenter bees. (Carpenter bees are not pollinators because they “steal” nectar by cutting through the base of the flower.)

Other species of the same genus in Arkansas are: narrowleaf obedient plant (Physostegia augustifolia), foxglove obedient plant (Physostegia digitalis), and slender obedient plant (Physostegia intermedia). Physostegia virginiana can be distinguished by the combination of its relatively late flowering time and wider leaves with sharply toothed margins. The most similar species is Physostegia angustifolia, but it has narrowly lanceolate leaves (usually less than ½ inch wide) and primarily blooms in late spring to early summer.  Physostegia digitalis also has wider leaves, but they are less toothed and their bases distinctly clasp the stem.

  • Physostegia virginiana has multiple forms of which two have been classified as subspecies, namely, Physostegia virginiana subsp. praemorsa and Physostegia virginiana subsp. virginiana. Subspecies praemorsa is said to have larger flowers, to form clumps, and to favor upland prairies and glades in comparison to subspecies virginiana which is said to have smaller flowers, to form colonies via rhizomes, and to favor wetter bottomlands and streambanks. Wild Arkansas plants have all been classified as subspecies praemorsa by most authorities, but there may be several different forms in the state, and it remains unclear as to what names best apply (perhaps both subspecies listed above, perhaps varieties or species synonymized under those two, or perhaps as yet undescribed entities).  To confound the issue, the species is commonly cultivated and cultivars may escape into the wild.  The species is in need of further field and taxonomic study.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Wood nettle

Wood nettle (Laportea canadensis) of the Nettle (Urticaceae) family is a perennial forb cloaked in needle-like, translucent, painfully stinging hairs. The genus name honors French naturalist Francois Laporte who studied the fauna of North America in the 1840s. The specific epithet refers to Canada, the locality from which Linnaeus’s type specimen was collected. In the U.S., the species occurs from Louisiana to Oklahoma to North Dakota and thence across the country to the Atlantic and Gulf coasts. In Arkansas, it occurs statewide except for portions of the Mississippi Alluvial and West Gulf Coastal Plains. Wood nettle occurs as an understory species in mesic to wet habitats with fertile soils associated with wooded seeps, riparian forests and bottomlands. It is also called stinging nettle*.

Wood nettle spreads freely in its preferred habitat from seeds and rhizomes so that large colonies may develop. In the spring, erect light green stems emerge that have alternate tissue-thin bracts on their lower six inches, below the leaves. The erect, unbranched, terete stems are slightly zigzagged from one leaf base to the next. Stems, remaining light green to medium green throughout the growing season, reach a height of 2 to 3 feet, with well-spaced leaves. The hollow hairs (trichomes) contain various chemicals which, upon touch, are injected into unwary hikers, producing a burning or itching sensation that lasts for 15 or more minutes. Blooming in mid-summer, wood nettle has staminate and pistillate flowers on the same plant (monoecious), borne in separate panicles to 4 inches long.

Wood nettle - Laportea canadensisPhoto 1: Clump (5 inches wide) includes several plants with intertwined roots. White pointed buds, for next growing season, can be seen at base of current-year stems. Round holes are scars from previous-year stems.

Leaves are alternate (other Arkansas nettles have opposite leaves). The simple leaves are up to 8 inches long, including the 2½-inch petiole, with the largest leaves occurring mid-stem. Leaves are ovate, to 3 inches broad. The upper leaf surface, slightly rugose at maturity, is a deep green, while the lower surface and petiole are light green. Leaf margins are coarsely serrate with triangular teeth, except for the rounded to weakly wedge-shaped base. Leaf tips are attenuate, longer than the lateral teeth. Venation is pinnate, with midvein, secondary and tertiary veins of the upper surface depressed and veins of the lower surface strongly expressed in round-relief. Long stinging hairs are scattered around the petiole as well as along principal veins of the lower surface. Scattered, stubby hairs are spread across the upper surface. Lower leaves tend to drop off as the growing season progresses.

Wood nettle - Laportea canadensisPhoto 2: Wood nettle is an understory species in rich, moist areas. Alternate leaves have long petioles and coarse serrations. Photo April 26.

Wood nettle - Laportea canadensisPhoto 3: A monecious species, female panicles appear at stem apex (light green) while male panicles (whitish) appear lower down the stem. Photo September 2.

The pistillate flowers (without stamens), in one to several slightly zigzagged panicles, grow from the stem apex (where leaves are closely spaced) and, sometimes, from the next-lower one or two leaf axils. The panicles, erect early, become more horizontal as they mature. Panicles consist of a half-dozen or more straight secondary lateral cymes, set at about 55 degrees off the main axis, along with a terminal group of flowers. Lateral cymes are also set at about 55 degrees from their axis and alternate from side-to-side. Cymes consist of a series of short alternate peduncles, each of which has up to to eight or so tiny (1/16 inch wide) downward-facing flowers. Flowers attach to flat somewhat triangular flange-like pedicels that become more apparent as fruits mature. Flowers have two noticeable sepals positioned at opposite sides of the ovary. Ovaries are tipped by long slender styles which twist skyward so that pistillate panicles have a wispy appearance. The entire panicle is a light green and cloaked with stinging hairs.

Wood nettle - Laportea canadensisPhoto 4: Pistillate flowers hang downward and long wispy styles reach skyward. Each flower attaches to a flange-like pedicel.

Wood nettle - Laportea canadensisPhoto 5: Display showing underside of a pistillate panicle. Long tapering styles point skyward. Note various stages of ovary development. Darker green patches “on” the ovaries are the sepals.

Below the female inflorescence, several leaves subtend the staminate flowers (without pistils). Structure of the staminate inflorescence is much like that of the pistillate inflorescence; however, staminate panicles are horizontal to drooping. Staminate panicles, extending out from the main stem to about the base of the leaf blades, are light green to whitish, with few stinging hairs. The tiny male flowers (⅛ inch corollas) face skyward. Flowers have five sepals (no petals) centered by five stamens and an infertile central column, actually a rudimentary ovary. They are light to whitish green with a dark green rib centered on each sepal. Stamens have white filaments and anthers that extend outside the corolla. Once pollen has been released, staminate panicles wither.

Wood nettle - Laportea canadensisPhoto 6: Display showing staminate panicle. As shown, only a few flowers are at anthesis. Flowers have sepals with dark green midribs and white filaments and anthers.

Pollination is by wind. With release of pollen, staminate panicles dry, and developing ovaries on the pistillate panicles quickly extend out from the closely hugging sepals. At first green, the fruit becomes a shiny black color. Mature fruits (achenes) are flattened, smooth and ovoid with thickened centers and two points. One point is where the style attached to the ovary while the other point is where the ovary’s base attached to the pedicel. As the plant fades in the fall, the achenes drop.

Wood nettle - Laportea canadensisPhoto 7: With achenes nearing maturity, the plant is approaching dormancy. Note the flanged pedicels and dried staminate panicle lower on main stem. Round crinkly objects in lower left corner are seed heads of yellow wingstem/ironweed (Verbesina alternifolia). Inset, an underside view, shows achenes clasped by the sepals.

Wood nettle, although an interesting plant, would not be desirable for a garden due to its stinging hairs and propensity to spread widely in its preferred habitat. However, nettles are important host plants for butterflies such as the Question Mark and Red Admiral, along with a number of moths.

  • Wood nettle (Laportea canadensis) is the only species of the genus in Arkansas. However, other native nettles found in the state may be confused with wood nettle, namely stinging nettle (Urtica chamaedryoides), stinging nettle (Urtica gracilis), clearweed (Pilea pumila), and false nettle (a.k.a. bog hemp) (Boehmeria cylindrica). Of these four, only U. chamaedryoides and U. gracilis have stinging hairs; however, their leaves are opposite and their inflorescences are completely different. The potent stinging nettle, Urtica dioica, is not currently reported in the state, but it too has opposite leaves.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Gum plant

Gum plant (Grindelia lanceolata) of the Sunflower (Asteraceae) Family is a viscid (sticky) plant with thick leaves. The genus name recognizes the early 19th-century Russian botanist, David Grindel. The specific epithet refers to the lance-shaped leaves. In the U.S., the species ranges from New Mexico to Ohio and Kentucky, as well as Wisconsin and Connecticut. In Arkansas, it occurs throughout much of the Ozarks and Ouachita Mountains. Habitat preference is sunny areas with rocky soils associated with limestone, sandstone or shale, where soils are generally dry to seasonally moist, especially glades, prairies and roadsides. Other common names include narrow-leaf gumweed, spiny-toothed gumweed and fall gumweed.

Gum plant is a short-lived perennial with fibrous roots along with one or several woody rambling fairly short taproots. The entire plant is glabrous (without hairs) and may feel viscid due to resinous pores. A mature plant has a half-dozen or more mostly erect, stiff, herbaceous stems. Stems, to 3 feet tall, typically have a half-dozen or more branches in their upper two-thirds. These branches, in turn, typically have 0 to 4 secondary branches. The slightly striate stems are light green to reddish in their actively growing upper portions while lower portions of a growing plant become tough and brown. All branches, which are arranged alternately, terminate with a solitary flower head. At the end of the growing season, erect dead stems may persist, even to the end of the next growing season.

Gum Plant - Grindelia lanceolataPhoto 1: Spring leaves of this mature plant in a highway right-of-way are basal-cauline leaves. Tough, hardened stems from previous year’s growth remain. Photo March 4.

Generally, the simple, alternate and ascending leaves are lanceolate with prominently serrate margins and acuminate leaf apexes. Marginal teeth and leaf apexes are apiculate. Some plants may have entire leaves, especially near the inflorescence; these tend to be twisted with undulated margins. The sessile, thick leaves feel slightly to moderately viscid. Upper and lower leaf surfaces are medium green with lighter green mid-veins. Mid-veins are weakly expressed and secondary pinnate veins are obscure. Pores may be evident on upper and lower leaf surfaces. Leaf size gradually decreases from 4 inches long and ¾ inch wide at stem base to one inch or less long and ⅛ inch wide at stem apex. When soil dries, lower leaves die while new apical growth and flowering continues.

Gum Plant - Grindelia lanceolataPhoto 2: Leaf shape changes from stem base to stem apex (leaves have been flattened for photo). Cluster at upper left is a growing tip prior to branching of stem. Leaves of stem segment have been removed, but alternate leaf arrangement is evident. Photo April 29.

Gum Plant - Grindelia lanceolataPhoto 3: Leaf margins may be entire. Height of branches exceeds height of central stem. Older stems harden and become brown. Photo August 5.

Composite flower heads, when still in a tight bud, have a spherical burr-like appearance due to an involucre of closely spaced, linear to lanceolate bracts. With anthesis, as receptacles assume a shallow bowl-shape, the burr-like appearance becomes hemispherical. The bracts, up to ½ inch in length and 1/16 inch wide, have short flattened bases while the remaining length is terete (round) in cross-section. Bracts, extending outwards and upwards, are pliable with sharp apiculate tips.

Flower heads, with bright yellow ray and disk florets, reach anthesis in mid-summer with bloom period extending for a month or so as flowering at tips of newer branches continues. A mature flower head, to about 2 inches wide with a ¾ inch central disk, has about 30 to 35 ray florets and several hundred disk florets. Ray florets have strap-like ligules, to ¾ inch long and ⅛ inch wide, that are widest at their mid-section with a very gradual narrowing to a tapered base and apex. Flower heads are more viscid than other parts of the plant, and botanists have a devil of a time trying to dry these heads when preparing pressed specimens.

Gum Plant - Grindelia lanceolataPhoto 4: Thick lanceolate leaves are twisted. Involucres are spiky with apiculate bracts. Branches terminate with a single flower head. Photo August 5.

Gum Plant - Grindelia lanceolataPhoto 5: Display shows 1) flowerhead with disk florets beginning to open, 2) bottom of a bracteate receptacle and 3) a divided flowerhead showing the receptacle in cross-section and ovaries.

Ray and disk florets are both fertile, with ray flowers being pistillate (no stamens) and disk flowers being perfect. The tiny, tightly compressed disk florets (⅛ inch long) are tubular, with five triangular lobes; five elongate stamens have fused (connate) anthers that surround the style. Like a plunger, the style emerges from the circle of anthers, pushing the pollen out, where it becomes available for contact with pollinating insects. As the pollen is dispersed, the stigmas then split apart (bifurcate) to expose two elongate receptive stigmatic surfaces. Disk florets of the composite head flower centripetally, from the outside in–the oldest florets thus are at the periphery of the head, the youngest (often still in bud) are in the center.

Gum Plant - Grindelia lanceolataPhoto 6: Pollen-tipped anthers are exserted from younger florets in central portion of flower head, while around the perimeter exserted stigmas of older florets have bifurcated to expose stigmatic surfaces.

A fertilized floret produces a cypsela (indehiscent fruit from an inferior ovary, often called simply an achene). The light brown, smooth achenes are flattened and oblong with rounded bases and cut-off apexes. Apexes bear two straight smooth awns, often exceeding length of corolla tubes, which drop off as fruits mature. Achenes have a central rib on their smooth sides and thin lateral margins.

Gum Plant - Grindelia lanceolataPhoto 7: Fruiting head: With flowering completed, achenes fall from the receptacle, leaving only the phyllaries (bracts) of the involucre. A discarded awn is partially hidden by an achene. Photo October 15.

Gum plant, a short-lived perennial, may be an appropriate choice for a wild garden. It has thick attractive leaves and bright yellow flower heads with burr-like involucres. However, with dry soils, lower leaves die and the plant becomes “leggy”. Thinning of seedlings may be required. Gum plant flower heads appear similar to those of many yellow composites, especially the taller woodland sunflowers, whose larger heads are in bloom at the same time.

In addition to Grindelia lanceolata, two other gum plants native to the south-central and western U.S. have been collected in Arkansas (though they may have been introduced to the state); namely, Spanish gold (a.k.a. wax gum plant or waxweed; Grindelia ciliata [or Prionopsis ciliata]) and curly-cup gum plant (Grindelia squarrosa). Grindelia ciliata, in comparison to G. lanceolata, has flattened, elongate-triangular floral bracts that are straight and leaves that are broader with margins spiny rather than serrated. Grindelia squarrosa, in comparison to G. lanceolata, has stubbier, sharply recurved floral bracts and shorter, wider leaves with less prominent serrated margins.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Hairy Blazing Star

Hairy blazing star (Liatris hirsuta*) of the Aster (Asteraceae) family has vibrant violet to lavender flowers, typical of many species in the genus. In the U.S., hairy blazing star is reported from Texas and northward to Nebraska and Iowa, with scattered reports in Mississippi, Alabama, and Georgia. In Arkansas, it is found throughout much of the state except for lowlands of the Mississippi Alluvial Plain and West Gulf Coastal Plain. The origin of the genus name has been lost. The specific epithet is Latin for “hairy”. Habitats consist of sunny rocky outcrops, glades and prairies with fairly well-drained soils. Other common names include hairy gayfeather (based on flower appearance) and Rydberg’s blazing star (described by Per Axel Rydberg in 1931).

Hairy blazing stars have globose corms with tops covered with short peaks that served as the bases for previous stem growth and a rounded to knobby bottom from which long skinny white roots grow. New growth buds, appearing across the corm’s top in mid-winter, produce only tufts of basal leaves or stems that have same-appearing “basal” leaves. Stems, unbranched and terete with a length of 2 to 4 feet, are light green with slightly raised darker green ribs that extend down from leaf bases. The slender stems, to about ¼ inch in diameter, have a slight taper from base to apex. Stems, not having “extra” girth at point-of-attachment to the corm, typically become reclined unless supported by other stems or other vegetation. Stems and leaves are roughened by straight, spreading hairs.

Hairy Blazing Star - Liatris hirsutaPhoto 1: This corm, with eight stems, is 3 inches in diameter and 2 inches thick. Fibrous roots grow from knobs at the base. Photo early August.

All leaves are linear to linear-lanceolate with the largest (to 8 inches long and 1/8 to 1/3 inch wide) being basal-cauline leaves. Size of cauline leaves gradually decreases up stem, with uppermost leaves being ¾ inch or less long. Pliable spring leaves become stiff, rough and twisted as the growing season progresses. Leaf color is medium to dark green above and below, with the upper and lower midvein being the same light green as the stem. Upper leaf blade to either side of the midrib tends to be up-turned (involute), especially at the entire (smooth), somewhat crinkly margins. Venation, largely obscure, is parallel to leaf margins with the upper midvein slightly expressed while the lower midvein is slightly depressed. Pubescence occurs on upper and lower surfaces of leaves and along leaf margins (ciliate pubescence).

Hairy Blazing Star - Liatris hirsutaPhoto 2: In this sunny, rocky habitat, new stems become apparent above their basal leaves. Previous year’s dead stems are splayed around the new growth. Photo early May.

Cauline leaves, positioned all around the stem, are sessile while lowermost leaves are also clasping. Leaf separation decreases from ½ inch (lower of stem) to ¼ inch (higher on stem). Cauline leaves are slightly narrowed near their bases and have a gentle taper to their acute apexes.

Inflorescence of hairy blazing star, in mid to late summer, consists of composite flower heads. Along with a solitary flower head at stem apex, additional lateral heads grow from upper leaf axils. Generally, wherever the lowermost lateral flower head occurs, almost all higher-up leaf axils also produce flower heads. Depending on age of plant and its habitat, a vigorous stem may have 40+ heads attached to its upper 18 inches. Flower heads mature and reach anthesis from stem apex, downward. Lower flower heads of a vigorous plant may be on short branches with a leaf or two (or even a lateral flower head or two), while higher heads may be on short pedicels attached to the stem or may be attached directly to the stem.

Flower heads of hairy blazing star have disk florets only (discoid head); ray florets are absent. Heads have tightly bound, spindle-shaped involucres that are to about ¾ inch long and ⅜ inch wide. Involucral bracts (phyllaries), in six to eight overlapping (imbricated) series and of unequal size, are oval to oblong, spreading, and with acutely-tipped, recurved apexes. Inner phyllaries are smaller, with shorter recurved tips. Lower portions of phyllaries are firmly pressed together, but can be separated with little effort. Phyllaries, mostly glabrous, have ciliate margins. Involucres, which feel hard and bristly, may be purplish in sunnier sites.

Hairy Blazing Star - Liatris hirsutaPhoto 3: The flower heads do not have ray flowers. In this photo, the terminal flower head has passed anthesis. Pubescence of stem, leaves and involucres can be seen. Photo late July.

Disk florets, 10 to 20+ per head and ⅖ to ⅗ inch long, have corollas that are a vibrant violet to lavender color. At anthesis, the corollas each have five short lobes that flare outward from long tubular bases. Pistils have a bifurcated style that exceeds the length of the tube. The “arms” of the style, joined inside the tube, twist-about in random, rather wispy fashion. Stigmas are not noticeable. Stamens, hidden within the floral tube and attached to the tube’s base, have long slender filaments with equally long and slender brown to purple anthers that split lengthwise to release white pollen. Corollas, set atop elongate inferior ovaries, are surrounded by a ring of long hairs (pappus) that are half the length of the tubes.

Hairy Blazing Star - Liatris hirsutaPhoto 4: Buds of the tubular florets have round-pointed apexes that flare open to expose five lobes. Styles are strongly exserted while stamens are hidden within the tube. Photo late July.

Hairy Blazing Star - Liatris hirsutaPhoto 5: Display of florets from bud to anthesis (right to left). Corollas and pappus attach to top of elongate ovaries. Inset shows ovary with pappus (left), style (right, removed from ovary), and anthers within cut-away corolla tube (center).

After the growing season, plants dry and involucres disintegrate. One-seeded, indehiscent, elongate fruits (cypselae), ¼ inch long, with fluffed-up pappus are dispersed by wind. The ribbed cypselae have flat tops with flared long hairs (pappus) and tapered bases. Fertilized and unfertilized cypselae have the same appearance, but fertilized cypselae are more firm.

Hairy Blazing Star - Liatris hirsutaPhoto 6: With involucre disintegrating, cypselae are set for wind dispersal. Photo mid-December.

For a garden or natural area, blazing stars should be welcome due to their long-lived nature, adaptability to rocky soils, their texture and strong flower color. Blazing stars are also good nectar plants for butterflies. Among the at least ten species and additional varieties native to Arkansas, are several that have a more upright structure and may fit better in a limited space. Of the other Arkansas species, the one most similar to hairy blazing star is scaly blazing star (Liatris squarrosa). The main characteristic that helps identify hairy blazing star is that the involucral bracts are spreading to recurved (instead of ascending to spreading) and outer bracts are shorter than inner bracts.

  • Some authorities classify this species as Liatris squarrosa var. hirsuta.

Article and photographs by ANPS member Sid Vogelpohl

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