Know Your Natives – Wild Comfrey

Wild comfrey (Cynoglossum virginianum) of the Borage (Boraginaceae) family is a short perennial with large leaves and pale blue flowers. In the US, it occurs from Texas to Illinois to New York to the Atlantic and Gulf Coasts. In Arkansas, it occurs statewide except for some areas of the Mississippi Alluvial Plain and lower elevations of the West Gulf Coastal Plain. The genus name, from Greek, translates to “hound’s tongue” in reference to leaf shape. The specific epithet references the State of Virginia from which it was originally described. It is also known as giant forget-me-not and hound’s tongue. Preferred habitat is open woodlands of ridges, slopes and bottomlands with rich moist soil where competition is low.

Wild comfrey - Cynoglossum virginianumPhoto 1: In its preferred habitat, a seeded colony stands out.

Wild comfrey has a ropy taproot from which new growth emerges from one or two buds in early spring. It may have a basal rosette of leaves only or, on more vigorous plants, a leafy flowering stem as well. Stems, to 2 or more feet tall, are erect, with the upper portion tending to be fistulose (hollow). Stems terminate with two divergent arching floral branches, often with an additional one or two widely separated branches below. Floral branches are initially coiled with flowers along the upper side in two ranks, alternating from side to side (a scorpioid cyme). A single flower may occur between the two apical floral branches. Each floral branch has up to 10 or more flowers. With large erect to ascending leaves, flowers seem to float just above the bulky plant.

Wild comfrey - Cynoglossum virginianumPhoto 2: In early spring, the first leaves are rising from the duff.

On a flowering plant, lower leaves are closely spaced along the stem while upper leaves are widely spaced. Large lower leaves, which may be ten or more in number, are elliptic with a gently tapering base and an acute apex. Largest of the lower leaves may be 14 inches long, including 4-inch petioles, and 4 inches wide. Lower stem leaves have wings that extend a short distance down the petiole. Above mid-stem, leaves become smaller and widely spaced with longer and wider wings so that leaves are sessile. These mid-stem leaves also become clasping and one or two leaves have ear-shaped appendages (auriculate) at their base. The uppermost several leaves are broadly lanceolate and clasping. Floral branches are leafless.

Wild comfrey - Cynoglossum virginianumPhoto 3: Mature plants produce a stem that terminates with the inflorescence. Upper stem leaves, with a broadened base, are sessile and clasping.

All leaves of wild comfrey are alternate with entire margins. Leaves are a medium green above and a light green below with yellowish petioles and main veins. Leaves have a sunken upper midrib and a prominently expressed lower midrib. Widely spaced pinnate secondary veins gently arch toward leaf apex while tertiary veins are reticulated and obscure.

Wild comfrey is heavily pubescent with fine, spiky hairs uniformly spread along the stem and both sides of leaves, along with ciliate leaf margins. Pubescence extends into floral branches and onto pedicels (flower stalks) where hairs are shorter and appressed. Pubescence is not present on the concave upper side of the sharply edged petiole or along the upper midvein. Pubescence of lower leaf surface is shorter than that of the upper surface. Stems and petioles feel hirsute while both leaf surfaces feel soft.

Flowers open about mid-May as the coiled cymes straighten. All of the two to five cymes on a stem develop at the same time with flowering proceeding from proximal to distal end. By the time the distal flowers are in bloom, fruits of the lower flowers are already well formed. Flowers are present for about a month.

Wild comfrey - Cynoglossum virginianumPhoto 4: This early stem, with inflorescences still crowded, terminates with two divergent scorpioid cymes with a separate lower cyme.

Flower buds are whitish with pink overtones, with corollas set in a medium green to purplish, densely pubescent calyx. Calyx lobes are twice as long as the calyx tube. With anthesis, corollas become pale blue. Flowers, up to half-inch wide, have a short tubular corolla with five lobes.. Lobes have whitish, raised appendages at their bases that form an elevated ring around a gaping throat. Lobes are oval and weakly flared with crinkly margins. A pistil and five stamens do not exsert from the corolla tube. Stamens, with short filaments adnate to the corolla tube immediately below the gaping center, have elongate lumpy anthers. The greenish stubby and erect style, positioned below the anthers, attaches to a round ovary.

Wild comfrey - Cynoglossum virginianumPhoto 5: Whitish buds become pale blue as flowers reach anthesis. Note elevated ring around throat and dense appressed pubescence on pedicles and calyx.

With fertilization, flowers immediately begin fruit development. The round ovary divides into four ovoid segments, each of which may produce a mature nutlet. Mature nutlets are grayish brown with a spiky clinging surface. Nutlets are dispersed by gravity, water flow, or various mammals to which the nutlets cling.

Wild comfrey - Cynoglossum virginianumPhoto 6: Whitish flower buds are nearer distal end of coiled cymes than blue flowers. Ovaries split into four spiky nutlets while style is still present.

For a shaded moist garden or natural area with minimal competition, wild comfrey should be a favored selection. With or without a flowering stem, the leafy plant is showy, especially in spring when it quickly reaches its maximum height. The pale blue flowers provide a subtle show. Wild comfrey is not noted for aggressive self-seeding; however, seeded cymes may be easily removed. It is not favored by deer.

In addition to wild comfrey (Cynoglossum virginianum), other species in the genus that have been recorded in Arkansas include three non-natives: 1) hound’s tongue or garden comfrey (Cynoglossum officinale) (in several northern counties), 2) Ceylon hound’s tongue (Cynoglossum zeylanicum a.k.a. Cynoglossum furcatum) (in several southwestern and central counties) and 3) blue hound’s tongue (Cynoglossum creticum). These species can be readily distinguished from Cynoglossum virginianumCynoglossum officinale has downy stems, small leaves and purple to reddish flowers. Cynoglossum zeylanicum, with blue flowers, is a tall multi-stemmed species with small lanceolate leaves and more numerous and longer floral branches. Cynoglossum creticum has smaller, narrower and stiff leaves, with many leaves up stems.  These introduced species are often found in disturbed areas.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Eastern Bluestar

Eastern bluestar (Amsonia tabernaemontana) of the Dogbane (Apocynaceae) family is an herbaceous, long-living perennial with blue flowers. The genus name honors 18th-century Virginian physician Dr. Charles Amson. The specific epithet honors Jacob Tabernaemontanus, a 16th-century German physician and botanist and author of the New Herb Book. Other common names include blue dogbane, willowleaf amsonia and woodland bluestar. In the U.S., it occurs naturally from eastern Texas to southeastern Kansas to Illinois and thence southward and eastward to the Atlantic and Gulf Coasts. In Arkansas, it occurs statewide. Eastern bluestar’s preferred habitat is various rocky to loamy well-drained soils in sunny to partially sunny open woodlands, glades and stream banks, as well as moist soils of prairies.

Eastern bluestar may have one to multiple erect stems in early spring. In the case of older multi-stemmed plants, new stems grow from the perimeter of the root clump. Stems grow quickly, with apical clusters of blue, pointed, tightly wound flower buds being apparent shortly after stems emerge. Flowers open as stems grow to a height of about 2 feet. By that time, the inflorescence is at full-bloom, and secondary stems are growing from several upper leaf axils, just below the main inflorescence. These secondary stems angle out and upward from the main stem and soon overtop it, with final plant height to about 2½ feet. Yellow-green, glabrous stems are terete below and ridged above, buttressing the upper leaves that subtend secondary stems and floral branches. Cut stems exude a white (“milky”) sap, characteristic of many members of the dogbane family. Stems arch outward later in the growing season so that plants, especially when heavily fruited, may become twice as wide as tall.

Eastern bluestar - Amsonia tabernaemontanaPhoto 1: In early spring, stems of older multi-stemmed plants grow from perimeter of root clump. Apical clusters of tightly wound pubescent blue flower buds are quickly apparent.

Broadly lanceolate, alternate leaves have blades to 6 inches long and 2½ inches wide. Petioles, to 1 inch long, are slightly winged at base of leaf blade. Leaves are medium green on their upper surface, with a lighter colored mid-vein, while the lower surface is a lighter green. Margins are entire and slightly revolute. Leaves lack pubescence except for hairs along margins (ciliate). Venation, depressed above and expressed below, is offset pinnate with lateral veins arching toward leaf apex and disappearing before reaching leaf margin. Like the stems, cut leaves exude a milky sap.

Flowering period lasts for a month or more in early to mid-spring. Inflorescences, mostly produced at apexes of main stems, consist of several short floral branches of which one terminates the main stem and several others rise from uppermost leaf axils. These floral branches, which are rebranched, each have about a dozen flowers, so that the inflorescence of a single main stem may have a hundred flowers. Some secondary stems, with or without several leaves, may terminate with a floral “branch”. Floral branches typically form ragged clusters that are rounded both radially and across their convex tops. The entire cluster develops simultaneously. Those secondary stems that do not bear flowers become taller than the main stems.

Eastern bluestar - Amsonia tabernaemontanaPhoto 2: Upper leaves of these main stems subtend floral branches and secondary stems. Note leaf venation and pubescence of tightly wound flower buds.

Flowers, to ¾ inch wide, are pale blue overall, with five oblanceolate lobes that form a star-shaped corolla with a whitish center. Corolla lobes join to form a slender floral tube set into a tiny calyx that has five stubby, triangular teeth. Corolla lobes ascend at about 45 degrees from the corolla tube. Entrance to the corolla throat is small and covered with long, white, in-facing, soft hairs (villous pubescence) that extend into the corolla tube. Lobes and tube have a similar length (about 3/8 inch), while the calyx is about 1/16 inch long. The exterior of the corolla tube is a dark blue with a greenish dilated area below. The exterior of the dilated portion of corolla tube is villous.

Eastern bluestar - Amsonia tabernaemontanaPhoto 3: Flowers are set in tiny calyxes with greenish dilated corolla tubes, as seen on buds at left. Pale blue flowers have a whitish center with radiating hairs. Secondary stems grow from leaf axils below floral branches.

Flowers have an elaborate yet functional structure: a hidden, elongate style is topped by a knob-like stigma. The anthers of five hidden stamens form an incurved, cap-like ring around the stigma. Anthers and stigma are positioned in the dilated section of the tube just below the throat entrance. Staminal filaments arise from the wall of the tube just below the dilated area. Stamens and style are a pale yellow-green while anthers are a light yellow. The single style is attached to the top of two closely appressed but separate ovaries nested in the calyx.

Eastern bluestar - Amsonia tabernaemontanaPhoto 4: Flowers have tiny calyxes, styles with knob-like stigmas, and anthers on short filaments. Villous pubescence occurs on exterior and interior of floral tube.

With fertilization, the two ovaries of the pistil develop into two fruits, growing into straight to slightly curved, slender, bean-like pods that may be 5 or more inches long. Pods are stiffly erect and tapered to pointed tips. With maturity in early September, each of the brown pods slowly splits from tip to base along a single suture (a fruit technically called a follicle), revealing eight to ten cylindrical, dark brown seeds with slanted ends. The seeds drop to the ground as the pods slowly open. Plants remain leafy and green into fall, when they become a golden-yellow. In winter, persistent stems and papery leaves become light tan to silvery.

Eastern bluestar - Amsonia tabernaemontanaPhoto 5: With fertilization, the two ovaries of the pistil separate and lengthen into bean-like pods that may be 5 or more inches long

Eastern bluestar - Amsonia tabernaemontanaPhoto 6: In this early June photo, seed pods are maturing. Brown seed capsules in background are on American alumroot. Inset shows two pods from one flower (the pods still attached to the flower’s pedicel) and seed in September (each square is ¼ inch).

Eastern bluestar is recognized in American Horticultural Society’s 75 Great American Garden Plants as one of the most carefree native wildflowers. It is an ideal plant for partially sunny native plant gardens and natural areas with well drained mesic soils. It returns year after year in early spring as a leafy plant with reliable clusters of blue flowers and attractive foliage throughout the year. Top-heavy plants may be kept more erect by removal of seed pods and/or securing plants to a central stake.

Eastern bluestar - Amsonia tabernaemontanaPhoto 6: In this mid-November photo, leaves are an attractive golden-yellow.

Other species of the genus in Arkansas are: fringed bluestar (Amsonia ciliata var. tenuifolia), Ouachita or Arkansas bluestar (Amsonia hubrichtii), and shining or Ozark bluestar (Amsonia illustris). These three species have flowers similar to those of Amsonia tabernaemontana; however, Amsonia ciliata var. tenuifolia and Amsonia hubrichtii have very narrow, needle-like leaves. Of Arkansas’s bluestars, Amsonia illustris, with its wider leaves, is the most similar to Amsonia tabernaemontana, but Amsonia illustris can be distinguished by its narrower, thicker and shinier leaves, as well as by its drooping seed pods.

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Violet Wood Sorrel

Violet wood sorrel (Oxalis violacea) of the Wood Sorrel (Oxalidaceae) family is a small bulb-plant that bears shamrock-style leaves. The genus name is based on a Greek word for “acid”, in reference to the plant’s pleasantly sour taste. The specific epithet is Latin for “violet-colored”, referring to the flowers. It is found across the eastern U.S. from Texas to North Dakota to the Atlantic and Gulf Coasts, with the exception of Maine and New Hampshire. In Arkansas, the species occurs throughout the state. It grows in a wide variety of sunny to partially sunny sites and in a wide range of well-drained loamy to rocky or sandy soils of open upland deciduous and conifer woodlands, glades and prairies.

Know Your Natives - Oxalis violaceaPhoto 1: Leaves unfold as peduncles rise. Photo: mid-March.

Violet wood sorrel has scale-covered bulbs* that are up to ½ inch long and ¼ inch wide, just below soil surface. Mature bulbs feel spongy. Scales, growing from a small basal plate within the bulb, loosely surround the central growth point that produces leaves and inflorescences at the bulb’s apex. Outer scales deteriorate into a loose matted layer that covers the inner, lanceolate to triangular scales. The light orange-colored scales have three straight prominent outer veins. The underside of the basal plate produces thin fibrous roots that extend downward along with thin, short, near-surface stolons that bear single bulbils (aka bulblets) at their tips. Bulbils also develop directly from the basal plate. In favorable sites, a single bulb quickly develops multiple offset bulbs and, with quick multiplication, may form a tight clonal group of numerous bulbs of “all” sizes. Within a clonal group, one to several bulbs may grow a vertically positioned, icicle-like rhizome that replaces the bulb. In addition to rapid propagation by cloning, plants readily multiply by seed.

Know Your Natives - Oxalis violaceaPhoto 2: Some bulbs may produce a vertical icicle-like rhizome. Matted layer of right-center bulb removed to expose light orange scales. Photo: mid-March.

Know Your Natives - Oxalis violaceaPhoto 3: Bulbs may be replaced by a vertical icicle-like rhizome. Photo: late April.

Leaves, growing directly from the basal plate, have long, slender, glabrous and weak petioles to 4 inches long. Palmately trifoliate leaves bear three sessile, broad heart-shaped, look-alike leaflets tapering to the petiole (obcordate leaflets). Leaflets, with smooth (entire) margins, are up to ¾ inch long and 1 inch wide and tend to remain somewhat up-folded along mid-vein. The apical leaflet slightly overlaps lateral leaflets. The upper leaflet surface and petioles vary from a dull medium green to purplish green with leaflets of many clonal groups having a reddish to purplish lateral band at about mid-leaflet, with a break at mid-vein. Lower leaf surfaces range from being a lighter green to being completely reddish purple. Petioles may be up to 3 inches long above soil/duff surface, while a very weak underground portion may be up to 1 inch long, as determined by bulb over-cover. Petiole color may be a light green or a light purple. Above-surface petiole length is not self-supportive and below-surface portion is especially weak. With all bulbs and bulbils in a clonal group producing leaves, a larger clonal group is densely leafy. Leaves contain tiny, sharp, calcium oxalate crystals.

Know Your Natives - Oxalis violaceaPhoto 4: Bulbs produce leaves and inflorescences directly from upper side basal plates within the bulb. The two smaller plants grew from exterior of basal plate and additional bubils remain attached to the large plant.

In late winter to early spring, flowers are borne in umbels (all pedicels attached at same point to peduncle) of up to about 10 or more flowers. Larger bulbs may have a half dozen or more smooth, erect, naked peduncles (scapes). One or two flowers on a scape bloom at any one time. As early umbels produce flowers, additional umbels may rise from the duff so that flowering continues for a month or more. Flowers close into a tight cylinder in response to cooler temperatures and darkness and tend to remain closed until temperatures approach 60 degrees. The above ground portions of peduncles, mostly glabrous, are up to 6 inches long, while very weak underground portions may be up to 1 inch long, as determined by bulb over-cover. Peduncles and pedicels of the same size have the same appearance. Plants become dormant in early summer, but some plants produce a second bloom in late summer in response to rain; however, with the fall bloom, leaves are not present.

Know Your Natives - Oxalis violaceaPhoto 5: In late summer, plants may produce a second bloom at which time, leaves are not present. Photo: mid-September.

Half-inch wide flowers have a corolla composed of five violet to lavender (occasionally white) petals that are loosely interconnected at their lower margins. Petals, broadly rounded and slightly overlapping in spin-wheel fashion, have parallel main veins that are a darker color distally, and become dark green into the flower’s throat. The green coloration in the throat has white shading to both sides. The undersides of petals have similar coloration, although colors may be lighter. Corollas are set into narrow campanulate (bell-shaped) green calyxes of five free, elongate-triangular, green sepals, each with a callous orange tip (calcium oxalate crystals). Sepals are entire and glabrous.

Know Your Natives - Oxalis violaceaPhoto 6: As seen in this early March photo, a clonal group may produce many umbels. A couple of flowers in an umbel bloom at any one time, as additional umbels rise from the bulbs.

Flowers of violet wood sorrel have five longer stamens in an inner whorl that are surrounded by five shorter stamens in an outer whorl, along with a single pistil of five carpels. Nectaries are located at base of outer stamens only. The species is heterostylous, specifically distylous–the flowers are dimorphic. One morph has styles that are longer than the stamens (the “pin” morph) while the other morph has styles that are shorter than the stamens (the “thrum” morph). Flowers of any one plant or clonal group have the same morph. Pollen from a flower of one morph cannot easily fertilize another flower of the same morph, thus encouraging out-crossing. In sunny sites, flowers are oriented toward the sun in the day and remain in that position overnight. Glabrous seed capsules, round in cross-section with a gradually tapering upper portion terminating with a flattened tip, split into five vertical sections from which small, wrinkled, light brown seed are ejected.

Know Your Natives - Oxalis violaceaPhoto 7: A “pin” morph flower is shown on left (styles longer than stamens) and a “thrum” morph flower is shown on right (styles shorter than stamens). In the inset, shorter pistils can be seen below stamens (thrum morph).

This small attractive species would be ideal for a naturalized garden area where its inclination (in a sunny preferred habitat) to freely multiply would be welcomed. Violet wood sorrel, an early food source for small bees, is avoided by deer and rabbits. Humans may eat the leaves, but intake should be of limited quantity, due to presence of tiny sharp calcium oxalate crystals.

In addition to violet wood sorrel (Oxalis violacea), as many as four yellow-flowering native species of the genus occur in Arkansas: three “yellow wood sorrels” (Oxalis dilleniiOxalis florida, and Oxalis stricta) and “Texas wood sorrel” (Oxalis texana). Non-native rose or pink wood sorrel (Oxalis rubra or articulata) is also reported in the state. Flower color and the tendency towards purplish accents on the leaves readily separate Oxalis violacea from the four yellow species. The non-native rose or pink wood sorrel can be distinguished from Oxalis violacea by its horizontal rhizomatous roots, flowers that are a solid dark pink, and leaves that do not exhibit any purplish coloration.

  • Plants of the Oxalis genus are the only dicotyledons (two seed leaves) that have true bulbs. All other true-bulb plants being monocotyledons (one seed leaf).

Article and photographs by ANPS member Sid Vogelpohl

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Know Your Natives – Wild Ginger

Wild ginger (Asarum canadense*) of the Dutchman’s-pipe (Aristolochiaceae) family is a low-growing woodland spring ephemeral. It occurs throughout the eastern U.S. from Louisiana and Oklahoma to North Dakota thence eastward to the Atlantic Coast, except Florida. In Arkansas, it occurs throughout the Interior Highlands (Ozarks, Arkansas Valley, and Ouachitas) as well as on Crowley’s Ridge. The genus name originates from an ancient Greek name, asaron, of uncertain derivation. The specific epithet refers to the plant’s occurrence in Canada. Other common names include Canada wild ginger and southern snakeroot. Preferred habitat is shady deciduous woodlands with rich, mesic soils found in uplands, floodplains and rocky slopes.

Plants have shallow, branching, slow-growing underground stems (rhizomes) that are round in cross-section and smooth except for widely spaced nodes. Long, slender and down-trending roots, with attached fibrous rootlets, randomly grow from underside of rhizomes. Although rhizomes are slow-growing, thick colonies may form. Rhizomes of wild ginger have the taste and smell of culinary ginger (Zingiber officinale), thus the common names, but is otherwise unrelated to this Old World tropical plant.

WIld Ginger - Asarum canadensePhoto 1: Near-surface rhizomes are smooth and heavily rooted. New growth originates at terminal and lateral buds.

New vegetative growth originates from ascending buds at tips of main rhizomes and shorter lateral rhizomes that originate at nodes. Each vegetative bud produces a short underground ascending stem, bearing two alternate bracts, and terminating with one or two leaves. When two leaves are present, a single flower may occur between petiole bases. Additional growth of the rhizomes also originates at rhizome tips from separate buds.

Leaves are orbicular, broader than long, deeply and openly cordate, with two large half-circular lobes. Leaves, to more than 4 inches long and 6 inches wide, have an upper surface that is medium to dark shiny green while lower surface is a lighter green. Upper and lower surfaces have very short hirsute pubescence with hairs of lower surface being mainly along veins. Leaf margins are entire with short dense pubescence (ciliate). Leaf tips are obtuse to rounded. Principal venation of upper surface, consisting of a straight midvein and three lateral veins to either side, is depressed. Midvein extends from petiole to blade tip while the laterals extend from corners of the sinus toward leaf margins, in dendritic fashion. Blade surface, including the large basal lobes, is mostly planar with central area becoming sunken toward the petiole. Leaves are thin, but appear leathery, due to blade surface between veins being raised. The petioles, slender and grooved, are up to 11 inches long and are covered with long, fine, twisty to woolly pubescence.

WIld Ginger - Asarum canadensePhoto 2: Leaves, occurring singly or in pairs, are orbicular with deep, broadly-open sinuses at the bases.

Flowers, appearing in early spring, are on short (to 1 inch) peduncles and are ascending to resting on the ground. Flowers, to 1 inch long, have a thick-skinned, six-sided, bell-shaped (campanulate) calyx bearing three spreading to reflexed, triangular to long-acuminate, petal-like lobes. (A true corolla is absent.) When lobes are triangular, apexes typically terminate with abrupt, short, oblong points. Flower color is variable, but generally the exterior of the calyx cup is a light yellowish brown below, becoming a light to dark reddish brown above and across outside and inside of lobes. Reproductive organs are exposed when calyx lobes recurve to yield an inch-wide flower. Interior color of calyx varies from being entirely white to a yellowish green. A yellowish green calyx may have purple, geometric, six-sided markings that encircle the lower portion of the cup. Peduncles are densely covered with long, woolly, white to purplish pubescence that extends over calyx and exterior of lobes.

WIld Ginger - Asarum canadensePhoto 3: Single flowers grow from between pairs of leaves. Note pubescence on leaf blades, petioles and calyx. Leaf in upper right corner is a violet. Photo taken April 7th.

Flowers have 12 sturdy stamens that encircle a stout central column of six upright styles. Stamens and styles are reddish to purplish. Stamens are attached to top of the inferior ovary. Straight, narrow filaments bear anthers with tiny, pointed, sterile extensions, like clawed tips, between the pollen sacs. The upper portions of stamens are initially bent outward, but with anthesis, stamens become upright and the outer sides of anthers split open to release yellow pollen. At anthesis, clawed tips are pressed back toward flower center and down onto style column. Flowers have a scent similar to rotting fruit.

WIld Ginger - Asarum canadensePhoto 4: The twelve stamens have released their yellow pollen, some of which can be seen on the six stigmas. Six of the now-barren stamens are positioned between pistils (see star pattern) while other six stamens are positioned across stigmas.

WIld Ginger - Asarum canadensePhoto 5: After anthesis, stamens and styles shrink and colors fade. Photo taken April 20th.

With fertilization, the fruit capsule enlarges and then splits at the top across its six chambers while remnants of calyx lobes, stamens and styles remain. Stacked, dark brown, smooth, rounded seeds, with dark brown spongy-looking elaiosomes attached at one side, become dislodged as the fruit capsule dries. These elaiosomes, a food source for ants, are carried, with seeds attached, into ant colonies. After removal of elaiosomes, seeds are discarded by the ants. Thus, ants obtain food and the wild ginger has its seeds dispersed (an example of myrmecochory).

WIld Ginger - Asarum canadensePhoto 6: Fruit capsule has split to discharge mature, smooth, brown seeds with attached elaiosomes. Photo taken May 19th.

In a shady woodland garden, wild ginger with its attractive leaves, would be an easily maintained ground cover for borders or an infill between larger plants. This species is not aggressive, does not need tending, and is not eaten by herbivores. Leaves are known to cause skin irritation for some people. Rhizomes should not be used for culinary purposes, as they have been found to contain carcinogenic compounds.

  • Several varieties of wild ginger have been named by various authorities based on shape and length of calyx lobes. Some authorities, however, consider the variations too numerous and geographically intermixed for formal recognition.

Article and photographs by ANPS member Sid Vogelpohl

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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 ericinlr@gmail.com.

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 ramorganllc@gmail.com 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 lmorrison@bgozarks.org 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 ramorganllc@gmail.com 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

UPDATE: Due to the high chance of rain that is forecast in Fayetteville on April 21, this hike has been canceled.

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 ranunculus73@gmail.com 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 ericinlr@gmail.com.

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 brent.baker@arkansas.gov 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 ericinlr@gmail.com.

 

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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