Know Your Natives – Tall Coreopsis

Tall coreopsis or tall tickseed (Coreopsis tripteris) of the aster or sunflower family (Asteraceae) is the tallest of eight coreopsis species native to Arkansas. It occurs primarily from eastern Texas north to Iowa and Wisconsin and east to Pennsylvania and the Florida panhandle. In Arkansas, it grows throughout much of the state except for lower areas of the Mississippi Alluvial Plain and West Gulf Coastal Plain. The genus name originates from Greek words meaning “like a bug,” in reference to the bug-like appearance of the fruit. The specific epithet is from Greek words for “three” and “wings” in reference to the plant’s trifoliate leaves. Preferred habitats include sunny to partially sunny sites in various well-drained yet mesic soils in prairies, rights-of-way, thickets, open woodlands, and wood margins, often along creeks.

Tall coreopsis is a herbaceous perennial that develops a tough caudex from which long ropy roots and rhizomes radiate. Rhizomes are segmented; each segment is subtended by an encircling growth-ring marked by a brown triangular bract. New clonal plants form at the ends of rhizomes. Caudices support one to several erect to leaning stems up to eight or more feet tall, unbranched except above in the inflorescence. Stems are slender, round, and hollow, glaucous when young, light green and glabrous, with slight rounded ridges. They bear widely spaced, opposite, decussate pairs of mostly compound, trifoliate leaves, about 2-3 inches apart. Petioles of the paired leaves have broadened bases which extend to form a ring around the stem.

Photo 1: This clonal rootstock has a “parent-rhizome” extending to lower left and a single stem extending to upper right. Rootstock has ropy roots and segmented new rhizomes and stems.

Trifoliate leaves measure about 5 inches long (including 1+ inch petioles) and 3¾ inches wide, with a central leaflet and two (sometimes four) opposite wide-spreading lateral leaflets. Leaflets are lanceolate, mucronate at the tips, the central leaflet to 3½ inches long, the laterals about 1 inch shorter. Lateral leaflets are sessile; central leaflets are stalked on petiolules* to ¼ inch long. Minute, soft pubescence (visible with magnification) covers upper and lower surfaces of leaf blades. Simple leaves occur in pairs at the base of floral branches, decreasing in size to become the bracts and bracteoles of the inflorescence. Crushed leaves have an anise scent.

Photo 2: In this late June photo, glaucous stems bear compound, trifoliate leaves with lanceolate leaflets. Stems have slight longitudinal ridges.
Photo 3: Compound leaves occur along the stem with simple leaves at and within the inflorescence. Secondary and tertiary veins are obscure. Photo – July 26.

The inflorescence, at the upper portion of the stem, consists of flowerheads supported by erect glabrous pedicels (to 1 inch), peduncles (to 2½ inches), and branches (to 6 inches). The lower branches tend to be longest. Blooming extends over a month in mid-summer. 

Photo 4: In this early August photo, the tall stems tend to lean. Flowerheads have a dark central disk.

At anthesis, flowerheads have a bowl-shaped, double involucre: an inner series of 6-10 yellow-green, broader, longer phyllaries, reflexed at their tips, and an outer series of narrower, bright green, ascending phyllaries.

Flowerheads are 1+ inch wide, with 6-10 bright yellow ray florets and 40-50+ disk florets. The showy ray florets are sterile, serving only to attract pollinators. Disk florets have reddish brown, tubular corollas (with five short, triangular, recurved lobes) and an equal number of stamens that become strongly exserted. Anthers are fused into a tube through which the style emerges, carrying and exposing the yellow pollen to pollinating insects. With pollen of the disk florets dispersed, the style divides and recurves to expose two elongate stigmatic surfaces. The central disk is flat before disk florets open, but becomes “prickly” as florets bloom sequentially from perimeter to center.

Photo 5: Pubescent inner phyllaries and linear-oblong outer phyllaries (brown tipped) can be seen on flowerhead at right. At left, corollas of sterile ray florets are fully extended while some disk florets are releasing pollen. One disk floret (upper left) has matured to show its bifurcated stigma.
Photo 6: Lower surface of flowerhead, right, shows dull yellow tips of the inner phyllaries at the base of the bright yellow ray florets as well as the green, ascending outer phyllaries. Flowerheads have been removed from pedicel/peduncle at left.

Disk florets that are fertilized form achenes (“cypselae” in the aster family) that vary in appearance depending on position within the central disk. Achenes at and near the perimeter are flattened, thin, and ovoid with narrow lateral wings as well as a concave and a convex side. Achenes at and near the disk center are elongate and wingless. All achenes are dark brown to black at maturity and truncate at apex and base. Seed dispersal is by wind and gravity, and sometimes subsequently by water.

Photo 7: Three disk florets are shown at left. On the flowerhead, three disk florets have exserted anther tubes and pollen has been released. Three maturing winged achenes (from a different flowerhead) are shown at lower left.

In a garden setting, tall coreopsis would be best suited for a natural area, due to its ability to develop colonies from rhizomes and self-seeding. Foliage and flowers are both attractive. Plants lean when bearing flowerheads due to the height of their slender stems. It is not bothered by deer.

Tall coreopsis, one of eight native Arkansas species in the genus, can be distinguished from the other species by a combination of its 1) height, 2) trifoliate compound leaves composed of lanceolate leaflets, 3) late period of bloom, and 4) reddish-brown central disk.

*Petioles are stalks of leaves. Petiolules are stalks of leaflets. Pedicels are stalks of a single flower or flowerhead. Peduncles are stalks of cluster of pedicels.

Article and photographs by ANPS member Sid Vogelpohl

Terms of Use

Posted in Know Your Natives | Tagged , , , ,

ANPS Fall 2019 Meeting Reminder

⏰HURRY – Only three days left!

Make your reservations now for ANPS Fall Meeting

Arkadelphia – Caddo Valley

Hotel Location:

Hampton Inn
108 Malvern Road
Arkadelphia, AR 71923
870-403-0800

Meeting Location:

Parks & Recreation Center, Feaster Park
2555 Twin Rivers Drive
Arkadelphia, AR 71923
870-246-5499

We have 15 double queens at $109 per night plus tax and 5 single queens for $89 per night plus tax. Breakfast is included. Be sure to mention that you are with ANPS when making your reservation. More rooms can be had at same rate if available.

Both Live Auction and Silent Auction on Friday Night – bring your wares!

Directions and Field Trip Details to follow next week.

In the interim, see the recent Fall issue of The Claytonia for more information or click here.

Posted in Know Your Natives

Know Your Natives – Missouri Ironweed

Missouri ironweed (Vernonia missurica) of the Sunflower or Aster (Asteraceae) family has vivid purple to magenta composite flowerheads in midsummer. The primary area of occurrence extends from western Florida to eastern Texas, north and east to Indiana and southern Michigan. In Arkansas, the species occurs throughout most of the state, though apparently absent from portions of the Ozark Mountains. The genus name commemorates William Vernon, an English botanist who worked in Maryland in the late 1600s. The specific epithet means ‘of Missouri’, in reference to where the species was originally described. Preferred habitat consists of various moist to mesic loamy to sandy soils found in low lying areas of prairies, woodlands, and drainage ditches.

This sturdy herbaceous perennial has a root crown with a mass of whitish ropy roots. New stems sprout from the periphery of the crown as central old stems die and form a tough, hard rootstock. Rhizomes, to a foot long, may extend from this rootstock and terminate with an offset clonal plant.

Photo 1: Current-year stems grow from the root-crown (as shown) as well as from short rhizomes. Circular scars are remnants of old stems.

Missouri ironweed is an erect herbaceous perennial with one or more tough, erect, round, ridged stems 3-5(-6) feet tall. Stems are unbranched except at the upper nodes, where lateral branching terminates in flowerheads (see below), producing a large, showy inflorescence. Stems and branches bear a dense coat of short, soft, white, tangled hairs, especially along ridges, that continue onto peduncles (ca 1 inch long) and pedicels (ca ½ inch long).

Photo 2: Erect stems have leaves that are fairly evenly spaced and of similar size. Tomentose pubescence gives stems a whitish cast. Photo – May 16.
Photo 3: Branches, growing from upper leaf axils, attain a final height that is greater than the height of the short branches that terminate the main stem. Pubescence extends into the inflorescence. Photo – July 11.

The alternate, mostly lanceolate-elliptic leaves are widest at the middle. Larger stem leaves measure about 6 inches long and 1½ inches wide. Apexes are acuminate (gradually tapering); sessile bases (without petioles) to subsessile bases (very short petioles) are cuneate (wedge shaped). Bases may have a light purplish shading. Leaf margins have weak serrations with tiny white tips; serrations decrease toward base and apex. Upper leaf surface is medium green with a glabrous (hairless), whitish midrib, especially along the lower portion. Lower leaf surface is light to whitish green. The upper leaf surface feels slightly rough (the hairs are short and stiff but not readily seen), while the lower surface feels downy from the tomentose pubescence.

Photo 4: Leaves, with white-tipped serrations, have an acuminate apex and cuneate base. Lower surface (right) is densely soft pubescent which highlights venation.

Missouri ironweed’s inflorescence consist of flowerheads comprising up to 45 or more disk florets. Flowerheads are organized into small, flat-topped, cymose arrays terminating branches growing from the main stem and upper leaf axils. Flowering begins at the terminal clusters of the main stem and gradually spreads outward. A single stem may support 200 flowerheads. The overall inflorescence is flat-topped.

The heads’ urn-shaped involucres, ¼ inch long and wide, are composed of five to seven series of imbricated bracts, called phyllaries in the composite family. Phyllaries are tightly appressed their entire length, broadly ovate, and ciliate along the margins. They are dark green in the center, with lighter-colored margins that turn purplish when flowerheads are in bloom.

As heads start to flower, a thick broom-like cluster of hairs or bristles appears above the involucre. The “broom” constitutes the “pappus,”* a cluster of 12-20 hairs attached to the top of each ovary in the head. Purple to magenta tubular corollas soon push out of the encircling bristles, forming a showy, frilly flowerhead. Corollas have five sharply tipped recurving lobes, five stamens and a single pistil with an inferior ovary. The thin elongate anthers of the stamens form a tube around the style. As the style elongates through the anthers, it carries their pollen above the corolla, where it can be picked up by pollinating insects. Stamens soon wilt, after which the upper portion of style divides and coils backward to expose two elongate, now-receptive, stigmatic surfaces. Flowerheads are up to 1 inch across and ¼ inch high.

Photo 5: Flowering, that begins with the terminal cluster of the main stem, as well as at the center of individual arrays, gradually spreads outward. Lower portion of lateral branches are leafless. Photo – July 30.
Photo 6: A complete flowerhead is shown at center and a dissected flowerhead to left and right. A subtending leaf and a single floret are also shown. Note the distinctive, ciliate phyllaries and the brown pappus.

Shortly after florets pass anthesis, the corolla, stamens, and style drop off. The ovaries then dry to become flattened, elongate, ridged achenes (often referred to as cypselae in the sunflower family). Pappus fluffs up to form a circle of radiating hairs. As achenes dry, they are dispersed by breezes.

For a moist to wet natural area or native plant garden, Missouri ironweed provides good vertical structure and showy flowers that attract butterflies and other insects. It can do well in partial or full sun, as determined by its dependence on good soil moisture. It is not eaten by rabbits or deer. Once plants are established, control may be needed to restrict spread (dead heading and pulling clonal plants).

Missouri ironweed is one of seven ironweeds that occur in the state. Species with similar characteristics and that are also widespread in Arkansas are tall ironweed (Vernonia gigantea) and Baldwin’s ironweed (Vernonia baldwinii). Characteristics to distinguish Missouri ironweed, considering the somewhat variable leaf shape and pubescence of the three species, are 1) tomentose stems, branches, lower leaf surfaces and 2) appressed, pointed phyllaries with purplish margins, and 3) relatively large number of florets per flowerhead. Tall ironweed has blunt, appressed phyllaries, and Baldwin’s ironweed has appressed phyllaries with pointed recurved tips (involucres appearing bristly). Both have fewer florets per flowerhead on average than Missouri ironweed. Additionally, tall ironweed leaves are not tomentose on the undersides.  Where ranges overlap, ironweeds may hybridize.

*The pappus is a modified calyx, distinctive for the sunflower family. It takes a variety of forms, for example, bristles, scales, and awns. The pappus is often the agent of seed dispersal.

Article and photographs by ANPS member Sid Vogelpohl

Terms of Use

Posted in Know Your Natives, Native Plants, Wildflowers | Tagged , , , ,

Know Your Natives – Baldwin’s Ironweed

Baldwin’s ironweed (Vernonia baldwinii) of the Sunflower or Aster (Asteraceae) family is a tall plant with a vivid purple inflorescence. In the U.S., it occurs principally from central Texas north to Nebraska and Iowa and east to Illinois and Arkansas. In Arkansas, it is found in the northwestern two-thirds of the state, primarily within the Interior Highlands. The genus name recognizes William Vernon, an English botanist who worked in Maryland in the late 1600s. The specific epithet recognizes William Baldwin, the original collector of the plant. Habitats have somewhat dry to slightly moist soils in open upland-woods, prairies and rights-of-way.

This sturdy herbaceous perennial has a whitish root-crown from which numerous ropy roots extend in all directions. As central stems die at the end of the growing season, short (less than an inch) rhizomes extend from the old rootstock and produce new stems immediately adjacent to the dead stems. The dead woody core of the older rootstock persists.

Photo 1: Dead stems at center of rootstock remain from previous years’ growth. Roots may be several feet long.

Stems bearing current year’s growth are erect, straight, tough, and brittle, typically 3 to 4 feet tall, but occasionally taller in preferred habitats. Stems are unbranched below the inflorescence. Floral branches, up to 10 inches long, spread widely from the main stem at the top of the plant. Stems and branches are typically tomentose (with short, soft, dense hairs), however pubescence is variable from plant to plant. Stems are round in cross-section.

Photo 2:  New growth of Baldwin’s ironweed is conspicuous in early spring. Photo – May 4.
Photo 3: Erect stems and branches are typically tomentose. Lower floral branches are shown. Photo – July 13.

Plants bear alternate, lanceolate to lance-ovate leaves with acuminate apexes and rounded tapered bases. Leaves have a slightly shiny, medium to dark green adaxial surface and a duller lighter green abaxial surface. Leaves may be short-petiolate or sessile. Pubescence of stems and branches extends onto the petioles, as well as to the midrib and lower surface of the leaf. The upper surface of the leaf blade may be scabrous (rough) to nearly glabrous. Leaves are large from plant base to floral branches, up to 8 inches long and 2 inches wide. Larger leaves are serrate along most of their length, with minute bristly yet soft teeth where veinlets terminate.

Photo 4: Leaf shape varies from lanceolate to lance-ovate. Display shows adaxial side of leaves except leaf at right. Leaf at right is 8 about inches long. Note serrate margins. Photo – July 14.

Flowerheads of Baldwin’s ironweed consist of disk flowers only (no ray flowers). The showy, somewhat flat-topped inflorescence measures a foot or more across and comprises a complex, branching arrangement of the heads in cymose arrays. Pubescence of the stems and branches continues onto the peduncles (stalks of groups of flowerheads) and pedicels (stalks of individual flowerheads). Flowering sequence is from the center of arrays outward, with those that terminate the main stem blooming first.

Photo 5: Inflorescence consists of numerous flat-topped cymose arrays of discoid flowerheads. Photo – July 13.

Flowering begins in mid-July and continues for several weeks. Heads consists of a compact group of 15 to 35 (typically 20 to 30) disk flowers, set in a campanulate (bell-shaped) to spherical involucre. The involucre comprises 5 to 6 series (layers) of tightly imbricated (overlapping) phyllaries (bracts). Phyllaries typically bear acute, recurved tips, giving the involucre a bristly appearance. 

As anthesis approaches, heads develop a rusty-brown, dense, broom-like cluster of bristles. (This is the “pappus,” a modified calyx and a distinctive character of the sunflower family that takes a variety of forms, for example, in addition to bristles, scales and awns. The pappus often is the agent of seed dispersal.) Each disk flower produces a purple tubular corolla (occasionally pink and rarely white), with five acutely tipped, recurved lobes, which pushes up through the pappus and, en mass, forms an attractive flowerhead. Anthers of the 5 stamens are fused into a ring around the style. As the style elongates through the anthers, it carries the pollen above the corolla, where it can be picked up by pollinating insects. Stamens soon wilt, after which the upper portion of the style divides and coils backward to expose two elongate stigmatic surfaces.

Photo 6: Immature flowerheads around the perimeter of photo show a brown, broom-like pappus prior to appearance of corollas. In addition to the typical purple, flowerheads may be pink or, rarely, white. Note bristly involucres.
Photo 7: As corollas open, their lobes recurve and anther-tubes and styles emerge. White pollen is pushed upward from the anthers and displayed by the emerging styles. Styles then split to expose stigmatic surfaces.

Shortly after anthesis, the corolla, stamens and style fall from the flower, and the ovary matures to become a flattened, elongate, 1-seeded achene (often referred to as a cypsela in the Aster family)–the familiar sunflower “seed” is one such achene. The pappus, attached at the tip of the developing achene, fluffs-up to form a circle of radiating, ascending bristles. As achenes dry, they separate from the receptacle and are dispersed by breezes.

Baldwin’s ironweed may be appropriate in a larger garden–at 3-4 feet tall, probably best suited for a naturalistic garden or natural area. It readily grows in various well drained soils. Its purple flowers are showy and attract butterflies and other insects. It is not eaten by deer.

Baldwin’s ironweed is one of seven ironweeds known to occur in the state. Species that have similar characteristics and are also widespread in the state are tall ironweed (Vernonia gigantea) and Missouri ironweed (Vernonia missurica). The best characteristic to identify Baldwin’s ironweed, considering the somewhat variable leaf shape and pubescence of the three species, is its recurved phyllaries which cause involucres to appear bristly. Tall ironweed has blunt appressed phyllaries, and Missouri ironweed has appressed pointed phyllaries. Additionally, tall ironweed leaves are not tomentose on the undersides and Missouri ironweed flowerheads consistently have over 30 florets (sometimes upwards of 50).  Where ranges overlap, ironweeds may hybridize. 

Article and photographs by ANPS member Sid Vogelpohl

Terms of Use

Posted in Know Your Natives, Native Plants, Wildflowers | Tagged , , , , | 1 Comment

Know Your Natives – Shrubby St. John’s-wort

Shrubby St. John’s-wort (Hypericum prolificum) of the St. John’s-wort (Hypericaceae) family is a short-lived, deciduous shrub with spectacular bright yellow flowers. The genus name originates from Greek words for “above” and “picture,” from the practice of placing flowers above a wall-mounted picture to discourage evil spirits on St. John’s feast day. The specific epithet, meaning “many,” is perhaps a reference to the plant’s numerous stamens. The species occurs from eastern Texas to Minnesota, thence east to the Atlantic and Gulf Coasts, although rarely encountered along the outer coastal plains. In Arkansas, it occurs throughout most of the state, except for low-lying areas of the Mississippi Alluvial Plain and the West Gulf Coastal Plain. Habitats vary from partial to full sun in well drained dry to mesic soils of upland areas, from rocky outcrops to stream banks, fields, and woodlands.

Shrubby St. John’s-wort, to 4 feet tall and broad, has one to several ascending branches which divide repeatedly into a myriad of twigs. Shrubs are dense and rounded on sunnier sites but more open in partial shade. Older trunks and branches bear loose, papery bark that exfoliates to expose underlying smooth reddish to orangish-brown bark. 

Photo 1: The thin smooth bark exfoliates with age.
Photo 2: With bright light, the shrub develops a dense rounded shape.

Twigs become brown and woody during their first year of growth. They bear evenly spaced pairs of subsessile, opposite leaves. Low ridges extending between leaf nodes become indistinct in the second year of twig growth, due to bark exfoliation. Twigs may grow 6 to 12 inches or more per year, with greater growth on young plants and sterile shoots.

Leaves are linear-oblong with a cuneate (wedge-shaped) base and a mucronulate (short-tipped) apex, ranging from tiny to 2+ inches long and ⅜ inch broad. Surfaces are glabrous (without pubescence), shiny dark green above, dull medium green beneath. Margins are entire (without teeth), slightly wavy and revolute (rolled under). Axillary buds of the primary leaves (below flower-bearing portion of twigs) produce clusters of tiny secondary leaves. 

Photo 3: New twigs grow from previous year’s twig (on right). Note primary and secondary (axillary) leaves. New twigs have two slight ridges between primary leaf nodes.

Showy, yellow flowers bloom in early summer. They occur singly and in groups of three at and near the stem tips, typically a terminal flower and a pair of lateral, axillary flowers. Individual flowers (to 1 inch wide and ¾ inch high) remain at anthesis for one day, but with many clusters, shrubs may bear flowers for three weeks.

Photo 4: Flowers follow a pattern-of-three. As shown, the apical cluster has a terminal flower and two lateral clusters of three flowers. Note leaves subtending calyxes. (Larger leaves removed for photo.)

Smooth shiny flower buds mature from a pale green to yellow. With anthesis, five bright yellow petals (to ½ inch long and ¼ inch wide) reflex back onto the smaller sepals to expose a large, circular mass of closely spaced, golden yellow stamens. Straight, slender yellow filaments are tipped with round, golden yellow anthers. The androecium (stamens as a unit) encircles a prominent cone-like pistil, the ovary of which tapers to three stigmas formed by three united styles. As flowers fade, petals become golden brown before dropping off.

Photo 5: A dense androecium surrounds a conical pistil. Ovary consists of three compartments terminated by three united styles. Note leaves subtending calyxes.
Photo 6: Display shows petals (1), a small number of stamens (2), pistil (3), leaves that subtend calyx (4), and calyx with stamen stubs (5).

As pistils mature in late fall, their apexes and sides split and the ovaries become rusty brown capsules with three sharp points (styles). Black, flattened, oblong seeds are released as the flower-bearing portion of twigs dies.

In a garden or natural setting, shrubby St. John’s-wort would be an asset either as a specimen plant or in a loose group. As it tends to be a prolific seeder (perhaps another possible source of the its specific epithet?), seedlings may need to be removed; on the other hand, seedlings do provide replacements for short-lived shrubs. Seedlings may produce flowers by the third year. Bees (especially native bumblebees) and other insects are attracted to flowers for their copious supply of pollen; flowers produce no nectar. Not favored by deer.

Including the marsh St. John’s-worts, sometimes treated in the separate genus Triadenum, nearly twenty species of Hypericum occur in Arkansas, most with yellow flowers. Shrubby St. John’s-wort can be distinguished by a combination of its woody habit, large (as compared to the other Arkansas species) five-petaled flowers, densely packed androecium, and rounded-in-cross-section capsule. The species most likely to be confused with shrubby St. John’s-wort is five-lobe St. John’s-wort (Hypericum lobocarpum). Also a woody shrub, five-lobe St. John’s-wort has slightly smaller, more densely arranged flowers and capsules that are five-lobed in cross-section (hence both its common and scientific names).

Article and photographs by ANPS member Sid Vogelpohl

Terms of Use

Posted in Know Your Natives, Native Plants, Shrubs, Wildflowers | Tagged , , ,

Know Your Natives – Royal Fern

Royal fern (Osmunda regalis var. spectabilis*) of the Royal Fern (Osmundaceae) family is a large herbaceous fern with a crown of clustered spore cases (sporangia) on the fertile fronds (leaves). In the U.S., it occurs from eastern Texas to Minnesota and thence to the Atlantic and Gulf Coasts. In Arkansas, it occurs pretty much statewide. The genus name, according to some writers, originates from “Osmunder,” a Saxon name for Thor, the god of thunder. The specific epithet is from the Latin for “regal” or “royal,” in reference to the fern’s size and majestic appearance. The variety name is from Latin for “admirable” and “spectacular”. It is also known as regal fern and American royal fern (this being the only variety in North America). Habitat preference is partly to mostly sunny areas with consistently wet to occasionally flooded soils, such as shallow, slow-moving drainages, bogs, marshes, seeps, moist bluffs, and open wetlands.

Royal fern has a stout, elongate rootstock that may be oriented vertically (in less-wet habitats) or horizontally (in wetter habitats). Dense, black, wiry and tough fibrous roots completely shroud the rootstock. New fronds (leaves) emerge at rootstock’s apex, surrounded by stubs of previous years’ leaves. Apices of vertically positioned rootstocks may become elevated above duff level while apices of horizontally oriented rootstocks remain at duff level, in rhizome-like fashion.

Photo 1: This 2½ foot-tall plant has matted fibrous roots which enshroud a horizontally oriented rootstock that is 9½ inches long and 1¾ inches wide.

In early spring, new fronds appear as large fiddleheads which unfurl into smaller fiddleheads that unfurl into pinnae (leaflets). The large fiddleheads are initially covered with long, matted pubescence which drops off as the stipe (leaf stalk) and rachis (midrib) elongate. Unfurled leaves are bipinnate or twice-cut into pinnae (leaflets) and pinnules (secondary leaflets). Depending on the habitat and season, fronds may be erect, ascending or arching. Fronds gradually decline in the fall and, except for frond stubs, disappear over winter.

Photo 2: In early April, newly emergent fiddleheads are temporarily covered with matted pubescence.
Photo 3: Fiddleheads remain mostly closed as stipes elongate to several feet tall. Fern at lower right is lady fern (Athyrium filix-femina).

Fronds are typically 2 to 4 feet long (maximum about 6 feet) and about half as wide, with widely spaced, opposite pinnae that elongate to 12 inches. Fronds are sterile or fertile, both having the same vegetative structure. However the upper pinnae and pinnules of fertile fronds lack chlorophyll and are modified into clusters of spore-producing sporangia. Below the sporangia, fertile fronds have the same appearance as sterile fronds. 

Photo 4: Sporangia of plants on left are green while those of plants on right have become brown after release of spores. Lady fern (Athyrium filix-femina) at lower right and Christmas fern (Polystichum acrostichoides) at lower left.

Pinnae of both sterile and fertile fronds bear six to twelve pinnules to 2 inches long and ⅜ inch wide. Pinnules are alternate to offset-opposite, mostly oblong, with rounded apexes and rounded to truncate-oblique bases. Margins are slightly undulating and minutely serrate. Fertile pinnae are greatly reduced in size. Spherical sporangia, maturing from frond apex downward, occur in small, naked, short-stalked clusters. Initially dark green, due to the chlorophyll-bearing spores within, sporangia turn lighter green to golden brown as they mature and then split in half across the top to release the spores. Sporangia then wither, and in late spring, the entire upper spore-bearing portion of the fertile fronds quickly shrivels. The lower portion of fertile fronds remains green and photosynthetic.

Photo 5: An 18-inch long section of a 4-foot long fertile frond. Fertile (sporangium-bearing) pinnae are significantly smaller than sterile, photosynthetic pinnae.
Photo 6: Clusters of sporangia replace leafy pinnules at tips of fertile fronds. Sporangia split across their tops for spore dispersal.

With spores dispersed, the reproductive activity of the “sporophyte phase” of the fern’s life cycle concludes. In the soil, spores germinate to produce a prothallus, the “gametophyte phase.” The tiny, ephemeral prothallus produces not spores but gametes, sperm and egg. Mobile sperm swim through ground moisture to fertilize eggs that have remained attached to their prothallus. Fertilization then produces a zygote that in turn develops into a large, perennial sporophyte plant. Readers who have taken a general botany course may remember this complex, elaborate life cycle being described as an “alternation of generations.”

Royal fern would be an excellent choice for mesic (in shade) to hydric (in sun) areas of a native plant or fern garden. Like most temperate zone ferns, it is herbaceous, dying to the ground each winter. But from spring to fall, with its large, bold structure, yet elegant and graceful fronds, it is a striking addition to the garden, either as a single plant or as a colony.

Photo 7: In fall, fronds recline and become more yellowish. Photo–October 23.

In addition to royal fern, two other members of the Osmundaceae family occur in Arkansas: interrupted fern (Osmunda claytoniana) and cinnamon fern (Osmundastrum cinnamomeum). While royal fern has bipinnate leaves (pinnae fully divided into pinnules), the other two ferns have pinnate-pinnatifid leaves (pinnae deeply lobed but not fully divided). Also, sporangia of interrupted fern, unlike those of royal fern, are located on fertile pinnae below the apex of fertile fronds (about mid-frond, with sterile pinnae above and below). Cinnamon fern has entirely separate fertile fronds that bear sporangia only.

*Recent genetic studies suggest that the royal fern of North America is a separate species (Osmunda spectabilis), but this reclassification has not been fully accepted by the botanical community.

Article and photographs by ANPS member Sid Vogelpohl

Terms of Use

Posted in Ferns, Know Your Natives, Native Plants | Tagged , , , , ,

Know Your Natives – Climbing Rose

Flowers of climbing rose (Rosa setigera) of the Rose (Rosaceae) family, one of four native roses that occur in Arkansas, have a single layer of five pink (occasionally white) petals. The genus name is Latin for “rose,” the specific epithet, also Latin, means “bristle-bearing”. Climbing rose occurs in the U.S. from Texas to Wisconsin east to New Hampshire and the Atlantic and Gulf states. In Arkansas, it occurs in the northwestern three-fourths of the state. Another common name is prairie rose. Preferred habitat is fertile, dry-mesic to mesic soils, in partial to full sun along streams, woodland borders, fence rows, rights-of-way, and in prairie thickets.

Climbing rose produces long slender trailing or climbing arching stems and branches, along with fast-growing suckers that arise off the rootstock or off main stems. When supported by other vegetation or structures, plants may reach 15 feet tall. In open areas, stems arch so that mounds to 3 feet tall may form. When growing tips of branches touch the ground, roots emerge and a clonal plant is established. Stems and branches that extend along the ground without touching soil do not develop roots. New stems and branches, typically glabrous, are a light green the first year, later becoming light brown and woody.

Photo 1: In this fence row, competing for sunlight, climbing rose has support from surrounding vegetation.

Stems and branches of climbing rose have thick prickles which easily break off the epidermis when side-pressure is applied. Smaller diameter stems may have pairs of prickles just below leaf nodes. Larger diameter stems have a few to many additional prickles scattered along the internodes. The stout, down-turned prickles, to ⅜ inch long, have broad flattened bases (to ¼ inch) set parallel to the stem. Prickles, tapering to a very sharp hard point, hold stems and branches in place and provide some protection from herbivores.

Photo 2: Prickles on this vigorous sucker-stem are especially stout and numerous. Prickles are persistent on dead woody stems. Note stipules fused to the lower portion of the leaf petiole

Deciduous, odd-pinnately compound leaves, to 2 to 4 inches long and 2 to 3 inches wide, have three to five leaflets (one terminal leaflet and one or two pairs of laterals). Three-leaflet leaves tend to occur near the inflorescence, five-leaflet leaves away from the inflorescence and on more vigorous stems. Petioles (leaf stalks below lowermost leaflets) have a widened clasping base and lateral wing-like stipules that distally terminate with an acute out-flared ear-like tip (auricle). Margins of stipules are entire to finely toothed. Lateral leaflets have 1/16-inch-long petiolules (leaflet stalks); those of terminal leaflets may be ½ inch long. Abaxial (lower) surface of the petiole, rachis (midrib), and terminal petiolule bears stout to nearly invisible down-curved pricklets, along with stubby knobbed glandular hairs (stipitate-glandular pubescence).

Leaves have leaflets that are ovate to elliptic with rounded bases and acuminate apexes. Pinnate venation is conspicuous. Adaxially (above), leaflets appear rugose, the veins recessed below the blade surface. Leaflets are mostly glabrous, though fine pubescence may be present along abaxial veins. Revolute margins are serrate. 

Photo 3: Stem on left grew the current year (leaves removed) while stem on right (branches removed) grew the previous year. Note leaf coloration, extent of serrate margins, venation, and stipules adnate (fused) to petiole, forming narrow wings.

Inflorescences develop in mid-spring and consist of single or compound clusters of flowers that terminate new-growth stems and branches. A branch with a single cluster may have several to a half-dozen flowers. Larger stems may have up to 36 flowers on a half dozen floral branches further divided into secondary branches. A flower cluster on a secondary branch typically has three flowers, a terminal flower and two laterals with pedicels connecting at a common point. Central flowers of individual clusters are the first to bloom followed by those below. Flowering persists for several weeks to a month. Floral branches are subtended by smaller three-leaflet leaves. Within secondary floral branches, flowers are subtended by one to three lanceolate, half-inch-long bracts.

Photo 4: Stipitate pubescence extends from sepals to pedicels. If a pedicel has a node (see black arrows), pubescence stops at that point.

Flower buds are round in cross-section, with a constricted base, wide lower section and acutely pointed tip. Buds are protected by five narrowly triangular sepals that may have a few randomly-placed narrow lobes along their otherwise entire margins. Outer surface of sepals is stipitate-glandular as well as short tomentose. With anthesis, sepals become reflexed (falling off with fruiting).

Flowers are beautiful: 2½ to 3 inches wide, with five light to medium pink (fading to white) petals that typically overlap slightly in their lower half. Although scented, the flowers do not have the pleasant scent associated with most roses. (Occasionally, petals are white instead of pink.) The conspicuous androecium comprises numerous stamens with pale yellow filaments tipped by golden yellow anthers. (In the typical horticultural rose, most of the stamens are genetically converted to petals to create the double-multiple form.)

About 20 pistils are present. Their ovaries are sunken into the tissue of the receptacle (the stem tip), which forms an enclosing structure around them called a hypanthium. The styles form a tight column that emerges from the hypanthium at the center of the dense ring of stamens. Stamens, petals and sepals are attached to the summit of the hypanthium, sometimes called the hypanthial disc. The mature hypanthium with its enclosed seeds becomes a unique fruit: the rose hip.

Photo 5: The column of styles, surrounded by numerous stamens, emerges from the hypanthium through the hypanthial disc. Broad gently wide-notched petals have a central tip. Photo – May 29.
Photo 6: With petals removed, display shows 1) dissected pedicel, 2) sepals, 3) stigmas grouped at top of style column, 3a) style column, 3b) styles emerging from hypanthium, 3c) ovaries, 4) stamens, 5) hypanthium, and 5a) hypanthial disc. Note dry fibrous hairs within hypanthium.

Pistils that are fertilized mature into achenes (indehiscent, one-seeded fruits) within the developing hypanthium or hip, which becomes red and fleshy in late fall. The spherical, berry-like hip, ⅓ inch in diameter, retains the stipitate glands that were present even at flower bud stage and bears a scar of the hypanthial disc at its tip. Hips are eaten by various mammals and birds, thus effecting dispersal.

Photo 7: Display of leaves, hips and achenes. Photo – November 21.

In a native plant garden, this climber would need regular training and trimming. It would do well inter-planted with various other native vines and shrubs where a screening effect is desired.

In addition to climbing rose, at least nine other rose species have been documented in the wild in Arkansas, of which three are native: Carolina rose (Rosa carolina), white prairie rose (Rosa foliolosa), and swamp rose (Rosa palustris). Of these three, Carolina rose and swamp rose have consistently pink flowers. Climbing rose can be distinguished by its climbing nature and rooting of branch tips. A non-native climber, multiflora rose (Rosa multiflora) has smaller white to light pink flowers and comb-like (fimbriate) hairs on its stipules.

Article and photographs by ANPS member Sid Vogelpohl

Terms of Use

Posted in Know Your Natives, Native Plants, Wildflowers | Tagged , , , ,

Know Your Natives – American Snowbell

American snowbell or storax (Styrax americanus) of the Storax (Styracaceae) family is a large deciduous shrub with bell-shaped snowy-white flowers. The genus name is the ancient Greek name for a European species, Styrax officinalis. The specific epithet refers to the native range of the species. In the U.S., it occurs from Illinois and Virginia south to the Atlantic and Gulf Coasts. In Arkansas, it is found across the state except for the Highlands of the northwestern one-third of the state. An understory species in nature, it prefers hydric soils in and along borders of swamps, boggy areas and drainages. In its natural semi-shaded habitat, it is a broad shrub with an open structure.

A deciduous, non-suckering, multi-stemmed shrub with thin, smooth, finely textured bark, storax grows to about 15 feet. Older stems are finely mottled in gray and pale green while previous year’s twigs are finely lined in tans and browns. Twigs of new growth are light to medium green.

Photo 1: American snowbell is an understory shrub that favors wet soils. Main stems tend to be straight and ascending. Photo – May 12.
Photo 2: Main stems join near ground level. Bark is thin and smooth.

New twigs grow from terminal and lateral buds (buds are without protective scales) along previous year’s twigs. New twigs are covered with very short and dense woolly pubescence. The terminal bud and several distal lateral buds develop vigorous new leafy twigs with no or few terminal flowers. Lateral buds occur in pairs, one above the other. Proximal buds develop into less dominant leafy twigs that bear one to several individual flowers in leaf axils. While distal twigs may be 6 inches long, proximal twigs are shorter, to 3 inches long. These tend to die out within a year or two so that the interior of a shrub tends to be open. Twigs are slightly zigzagged.

Leaves are elliptic to oval with larger elliptic leaves occurring toward the twig apex and smaller oval leaves occurring toward the twig base. Large leaves may be 3 inches long, including a ⅛- to ¼-inch-long petiole, and 1½ inches wide. Small leaves, to as small as ¼ inch long, have the same proportions, with petioles remaining about ⅛ inch long. Pubescence of twigs decreases onto petioles and underside of leaf blades. New leaves have a medium green upper surface that darkens with age. The lower surface is paler.

Venation is prominent, with four to six widely spaced, off-set lateral veins. Secondary veins arch toward blade margins, but blend with tertiary veins a short distance from margins. Upper veins are recessed, lower veins expressed.  Tertiary veins form a reticulate pattern. Leaf margins are distinctive, bearing tiny soft-tipped teeth.

Photo 3: The divide between current-year twig and previous-year twig is indicated by the red arrow, the site of the previous year’s terminal bud. Inflorescences are borne on lateral twigs growing from lateral buds along previous year’s twig. Upper side of twigs shown.

Pendulous, bell-shaped (campanulate) flowers, blooming in May, are evenly distributed around the shrub, with flower-density greater in brighter light. Most flowers grow from leaf axils (axillary) sited along new lateral twigs, one or two flowers per leaf. Additionally, racemes of two to five flowers grow directly from the tip of lateral twigs (terminal flowers).

Photo 4: Underside of same twigs shown in Photo 3. Leaf axils of lateral twigs bear one or two individual flowers, while short racemes of flowers terminate the same twigs. Note differences in leaf color and venation between this photo and Photo 3.

Flowers are showy, and the shrubs are often used ornamentally. The corolla is sympetalous, with 5 snowy-white, recurved lobes, measuring about ¼ inch broad. The 8-10 white stamens form a compact group around the pistil. The slender white style extends just beyond the stamens. Stamens are free-standing in their upper two-thirds and fused to one another at their base. The ring of stamens is also fused to the base of the corolla tube. Anthers are elongate and vertically aligned with the filaments. They dehisce on their inward side to release yellow pollen. The style is tipped with a slightly green flat stigma. The corolla tube is set in a short, cuplike calyx rimmed with five short teeth.  Ovaries are superior. With the passing of anthesis, the corolla, with the stamen group intact, separates from the calyx, exposing the ovary. Pedicels are about ¼ inch long.

Photo 5: Display shows: #1) a flower bud (over-draped by a discarded corolla), #2) flowers at anthesis, #3) corolla and stamens separating from calyx, and #4) ovary within a calyx, with style still attached.

In mid- to late September, fertilized flowers produce globose, ¼-inch-long drupes that each contain a single nutlet surrounded by a thin but tough shell. Fruits are secured by pedicel and calyx until maturity. Exterior of fruit, calyx and pedicel are light yellowish green with a fine dense pubescence. As fruit develops, the shell splits along three lines from the base, while remaining connected at the tip. At maturity, the shell  becomes yellowish tan, ultimately opening fully and releasing a dark brown, hard globose nutlet.

Photo 6: Twig with leaves and fruit, the fruit before dehiscence held by the calyx and pedicel. Open fruit: shell dehisced from base to apex and globose nutlet fallen out.

American snowbell would be attractive in a garden or natural area with consistently wet soil and sufficient space for a large shrub. It can do well in a partially to fully sunny site. Sunnier sites will produce a denser shrub that has a greater floral display.

Big-leaf snowbell (Styrax grandifolius), a shrub to small tree, also occurs in Arkansas. American snowbell can be distinguished from big-leaf snowbell by its preference for hydric sites, its smaller, more-elliptic leaves, and fewer flowers per terminal raceme.

Article and photographs by ANPS member Sid Vogelpohl

Terms of Use

Posted in Native Plants, Wildflowers | Tagged , , , ,

Know Your Natives – Aniseroot

Aniseroot (Osmorhiza longistylis) of the Carrot (Apiaceae) family is a herbaceous erect perennial that has pleasantly aromatic roots. It occurs across most of the U.S. from New Mexico to Montana, thence east to the Gulf and Atlantic Coasts, with the exception of Louisiana and Florida. In Arkansas, the species occurs in the Highlands of the northwestern half of the state and on Crowley’s Ridge. The genus name is from Greek words for “aromatic root”. The specific epithet is from Latin for “long-styled”. Other common names include sweet anise, long-style sweet-cicely, and smooth sweet-cicely*. It occurs in moist deciduous woodlands with light to moderate shade in soils enriched with decaying plant material.

Plants have thick, branching tap roots that terminate in long fibrous roots. Crushed roots have an anise scent.

In spring, new buds sprouting from the caudex (stem base) develop into basal leaves and a compressed mass of developing stems, leaves and inflorescences. Fully developed basal and cauline leaves have three pinnate leaflets that may be further pinnately divided into sub-leaflets (ternately pinnate to bipinnate). At the end of the growing season, stems decay while basal leaves may become ground-hugging and persist into spring.

Photo 1: In this early January photo of branching taproots, previous year’s basal leaves persist (extending off top of photo) and buds for new growth can be seen on caudex.
Photo 2: In this early April photo, a mass of developing stems, leaves and inflorescences emerge at center of plant. The large basal leaves are bipinnately compound, as are cauline leaves that will develop later.

Above the basal leaves, mature plants have one or two erect, typically pilose (densely short-pubescent), solid stems that grow to a height of about 2½ feet. Nodes are rather swollen and bear single cauline leaves which may subtend lateral or floral branches. Stems are a light green with lower portions and areas near nodes sometimes purplish. 

Photo 3: Immature ternately bipinnate leaf has a clasping base from which a compound umbel (with white flowers) has grown along with a lateral branch that bears another developing umbel (hanging down). Photo – April 15.

The compound leaves, to about 9 inches long and 12 inches wide, are divided into three principal sections (ternately compound). Leaflets have thin, rather flimsy blades with prominent irregularly wavy (sinuate) margins. They are a dull light to medium green on both surfaces. Stalks of leaves and leaflets are rounded on their upper side and flattened and grooved beneath. Crushed leaves have a light anise scent. 

Photo 4: This plant has two ascending basal leaves and two well-developed, cauline leaves, of which the uppermost subtends a peduncle with white flowers in a compound umbel. Note fine pubescence along purplish stem.

Inflorescences, flowering in mid-spring, are terminal and axillary compound umbels, consisting of one or two slender peduncles about 2 inches long. These terminate in three to six rays, each tipped by 5 to 17 pedicels supporting the umbellets of flowers. Rays are subtended by an involucre of 1-6 bracts, the umbellets by an involucel of 4-6 bractlets. Umbellets bear about 5-17 flowers, of which 5-7 are perfect (having both pistils and stamens), typically arranged around the perimeter of the umbellet, and the rest staminate. Flowers bloom in quick sequence from the outside toward center of umbellets so that fruiting begins while staminate flowers remain at anthesis.

The perfect flowers have no sepals, five white petals, five stamens, and a pistil of two united carpels with two free styles. As flowers open, stamens are curved inward before becoming erect. Stamens and knob-like anthers are initially white, but anthers become light tan as pollen develops. Styles have an enlarged base, the stylopodium, a characteristic of most species in the carrot family. The inferior ovary bears white hairs along longitudinal ribs, similar to the ciliate hairs of the floral bracts. The open corolla is ⅛ inch wide; the ovary at its tip, just below the corolla, is about 1/16 inch wide.

Staminate flowers, about 1/16 inch wide, have more slender pedicels and small bowl-shaped receptacles. Petals and stamens of staminate flowers are similar to those of the perfect flowers, however, the petals remain crimped together–the corolla does not flare outward.

Photo 5: This compound umbel has four umbellets of which the lower three have perfect and staminate flowers while the upper umbellet has staminate flowers only. Stigmas are held well above corollas. Note ciliate pubescence of bracts and bractlets and the ribbed ovaries.

Ovaries that are fertilized mature into long (to 1 inch) slender dry fruits called schizocarps that split into two 1-seeded halves called mericarps. These are slightly flattened and have longitudinal ribs with stiff forward-appressed hairs. Styles are persistent on the mericarps as spiny projections. At maturity, mericarps separate from each other and from the central axis so that only their tips cling to the tip of the central axis. At full maturity, black mericarps are slightly curved with a long spiny proximal tip and a short spiny distal tip (the persistent style). As various animals or birds brush against plants, the spiny tips and side-hairs become entangled in fur and feathers, providing seed dispersal.

Photo 6: In mid-June, schizocarps have split into two mericarps that cling to tips of the central axes. Upper leaf section shows adaxial surface while lower leaf section shows abaxial surface. Dried remnant is the third leaf section. (Parts separated for photo.)

For a native plant garden or natural area with moist soil and partial shade, this non-showy perennial may add extra texture and help in-fill an area. This perennial member of the carrot family does not seem to self-seed agressively. Roots, flowers and leaves are edible in salads or as a garnish.

Fifty-five species of the Carrot family occur in Arkansas, of which a number have bipinnate leaves and compound umbels. Characteristics of aniseroot that aid in its identification include: 1) a perennial species, 2) branched tap roots that have an anise scent, 3) broad leaves with bluntly toothed leaflets, 4) short dense pubescence along stems, 5) umbellets with perfect and staminate flowers, 6) petals of perfect flowers that have clawed tips, and 7) linear fruits. Aniseroot can be separated from the only other Arkansas species in the genus, hairy sweet cicely (Osmorhiza claytonii), by aniseroot’s 1) shorter, less conspicuous pubescence, 2) styles that extend outside corollas, 3) fruits that have prominent spiny hairs on longitudinal ribs, and 4) a stronger anise scent.

*  The word “anise” relates to a non-native culinary species (Pimpinella anisum) which has roots and leaves that also have an anise scent. “Long-style” compares aniseroot’s style to the shorter style of hairy sweet-cicely (Osmorhiza claytonii). The word “cicely” probably originates from European sweet-cicely (Myrrhis odorata). Aniseroot is also called “smooth sweet-cicely” based on its lesser degree of pubescence, as compared to hairy sweet-cicely.

Article and photographs by ANPS member Sid Vogelpohl

Terms of Use

Posted in Know Your Natives, Native Plants, Wildflowers | Tagged , , , ,

Know Your Natives – Mayapple

Mayapple (Podophyllum peltatum) of the Barberry (Berberidaceae) family is an herbaceous perennial that has one or two large leaves per stalk. The genus name is from Greek words for “foot” and “leaf”, in reference to the appearance of  the leaves. The specific epithet, from Latin, is a reference to the vegetative leaf’s umbrella-like form, in which the petiole joins the leaf blade on its lower surface rather than the margin. In the U.S., mayapple, the only North American species of Podophyllum, occurs from Texas to Minnesota eastward to the Atlantic and Gulf Coasts. In Arkansas, mayapple occurs statewide. (A second species of Podophyllum occurs in east Asia.) Habitat consists of shady to partially sunny, mixed deciduous forest and forest edges with dry to mesic soils, along with moist open areas. Plants are also called American mandrake based on the superficial similarity to the unrelated European mandrake, Mandragora officianarum.

Mayapple develops an extensive shallow layer of reddish brown, rope-like rhizomes, to ¼ inch in diameter, that elongate annually by adding 2- to 8-inch-long straight segments. The ends of the segments have numerous down-turning fleshy white roots. Rhizomes do not have any noticeable growth nodes. With several new rhizomes branching from the ends of previous years’ segments, open to dense colonies may form with hundreds of leaves.

In late winter, vegetative growth develops from the terminal buds on previous years’ rhizome segments. The first growth to appear is a white “cone” formed by several imbricated protective bracts. As one to two large leaves develop, the cone spreads open. At first, leaf blades are down-drooped around hidden stalks so that the flat white centers of the leaves are the first leaf-portion to appear out of the cones. In the case of two-leaf stalks, two white centers appear, separated by an ovoid flower bud. Stalk growth quickly frees the growing furled leaf blades from their protective cone and they open umbrella-like.

Photo 1: This 3-inch tall, two-leaf stalk has furled leaves separated by a flower bud. Basal protective bracts quickly fade as stalks grow. Note marginal ciliate pubescence. Photo – March 16.
Photo 2: Terminal buds of previous year’s rhizome segments produce new stalks (extending off top of this photo). Basal protective bracts have become tissue-thin. White nubs will become new rhizome segments. Fleshy roots are concentrated below stalks. Photo – April 5.

Stalks, 1½ to 1¾ feet tall and ¼ inch in diameter, are erect, terete and glabrous. Stalks that support two leaves are forked at about two-thirds their height so that stem-length above the fork is 3 to 6 inches. Stalks bearing one or two leaves are of similar height and have the same light green to reddish coloration. Stalks are totally smooth. At the end of the growing season, stalks quickly disintegrate, leaving a round scar on the persistent rhizome.

Leaves, to 14 inches across, have an orbicular outline with up to nine shallowly to deeply incised lobes, depending on leaf size. Lobes are obovate in outline and separated by deep clefts. Leaves are a medium green above, often mottled, and a lighter green below. The upper leaf surface is glabrous, the lower surface and margins densely short-pubescent. Venation is strongly recessed above–creating a smoothly wrinkled surface–and strongly expressed below, with main veins dividing distally and terminating at the apiculate tips of the lobes. 

Photo 3: This colony may be a single plant (a clonal colony) or a number of intertwined plants. Photo – March 30.

Leaf shape of one-leaf stalks, with center of leaf blade attaching to stalk, is peltate. Leaves of two-leaf stalks have fewer lobes, the “missing” lobes directly above the fork in the stalk, so that leaf shape becomes off-set palmate (point of stalk attachment not fully centered) to palmate (point of attachment at leaf margin). One leaf of two-leaf stalks tends to be smaller than the other.

The mayapple inflorescence comprises a single flower positioned in the fork of two-leaf stalks. When stalks first emerge, flower buds are positioned slightly above and between the emerging leaf pair. With stalk and leaf growth, buds become hidden well below the large leaves. Buds, on slender sturdy pedicels to 1½ inches long, have three light greenish bowl-shaped sepals that drop off as the corolla swells. With anthesis, the large (to 3 inches wide) white flowers face downward. (Several rare forms of mayapple are known to occur.*)

Photo 4: Inflorescence consists of a single flower in the fork between the two leaves. Red buckeye (Aesculus pavia var. pavia) in background. Photo – April 4.

Flowers have five to nine petals, 12 to 15 stamens, and a single superior ovary. The white, waxy, obovate petals are 1½ inches long and wide. Stamens have ¼-inch-long pale yellow filaments and ¼-inch-long light yellow anthers that release pollen as they dehisce (split) along their lateral margins. The light green ovary is tipped by a prominent, pale yellow, crinkled stigma atop a short, stout style. Flowers are fragrant. Ovules are massed on a single broad placenta along one side of a central cavity.

Photo 5: Buds (bottom of photo) have three light-green sepals that drop off as flowers open. Flowers have five to nine overlapping petals, 12 to 15 stamens, and a large ovary (hidden in photo by crinkled stigma).
Photo 6: This half-inch-long ovary was dissected just after anthesis. Ovules are attached to a single placenta on the ovary wall.

A fertilized flower produces a berry that ripens in mid-summer. Mature fruit, about 1½ inches long, becomes pale yellow as leaves and stalk wilt and dry. Fruits drop to the ground where they become accessible to various small mammals as well as box turtles (Terrapene carolina), resulting in seed dispersal. The smooth seeds resemble apple seeds.

Photo 7: Leaves (at top of photo) have dried, while fruit remains green. Fruits have a flattened side. Prominent stigma is persistent. Photo – June 13.

Mayapple’s conspicuous foliage and colonizing tendencies may be welcome in a woodland garden or natural area where it would add a dramatic flair. The easily viewed parts of flowers and fruit can make it an educational tool. Gardeners can easily establish new colonies by transplanting rhizome segments as foliage declines. All above-ground evidence of plants disappears from summer until spring. Ripe fruit, with seed removed, is considered to be edible while all other portions of the plant (including unripe fruit) are known to be toxic. Mayapple contains podophyllotoxin, which is used in developing prescription drugs and for cancer research. Foliage is not eaten by deer or rabbits.

* Podophyllum peltatum forma deamii has pink-tinged flowers and maroon fruit. Podophyllum peltatum forma polycarpum produces a cluster of fruit. Podophyllum peltatum forma biltmoreanum produces orange fruit.

Article and photographs by ANPS member Sid Vogelpohl

Terms of Use

Posted in Know Your Natives, Native Plants, Wildflowers | Tagged , , , ,