Know Your Natives – Camphorweed “Blooms” Frost Flowers

Camphorweed (Pluchea camphorata) of the Asteraceae (Aster) Family occurs in the Southeast and lower Midwest from Texas and Kansas to Illinois, Ohio, New Jersey and southward.  In Arkansas, the species occurs statewide, though is somewhat less frequent in the central Ozarks.  Camphorweed, an annual to short-lived perennial herb, grows at the edges of ponds and lakes, in marshes, on creek and river banks, in bottomland forests and in other moist areas.  In its preferred habitats, this species can become weedy.

Camphorweed, a.k.a. stinkweed, marsh fleabane or Plowman’s-wort, is an erect plant growing three or more feet tall.  Plants, with one to several erect, round, hairy and semi-woody stems, have an almost overpowering, musky (camphor-like) aroma when handled.

Alternate, ovate to broadly elliptical simple leaves are largest mid-stem of main stems.  There is one leaf per node.  Leaves, on short petioles, are acutely tapered toward the tip and broadly tapered toward the base.  The leaves, which are sticky (due to glandular hairs), have shallowly serrate margins with widely spaced teeth.  The veins are pinnate and raised on the lower leaf surface.  The upper leaf surface is covered with sparse, soft hairs while the lower surface is more densely hairy.

Sweetscent in spring showing beginning of inflorescence.

Spring growth of Camphorweed with beginning of inflorescence at top of the stem.

Inflorescences in mid-summer consists of rounded clusters (panicles) of cream-colored to pinkish-rose-colored terminal flower heads at the top of small plants or at the ends of many branches and sub-branches on larger plants.  Each flower head has the outer flowers  pistillate, with a highly reduced corolla, and a smaller number of staminate central flowers.  As in all members of the Aster Family, the ovary is inferior, with the corolla attached at its tip.  Corollas of the central flowers are round (radially symmetrical) with five lobes, and appear bisexual with one style and five stamens, but the style is undivided and the ovary sterile.

The involucre, which supports the head as a calyx would an individual flower in most other families, comprises overlapping bracts (phyllaries) that are ovate to linear in shape and similar in color to the flowers.  The appressed phyllaries tightly clasp the flower head.

Large and small plants of Camphorweed in bloom.

Photo 3

A panicle of Camphorweed flower heads.  Note the infertile pistils on central flowers.

One-seeded fruits, in mid-fall, are tiny achenes tipped with a bristly pappus. Like closely related sunflower “seeds,” (what we call seeds are actually fruits), the wall of the fruit (pericarp) is not fused to the seed inside.

Photo 4

Camphorweed in seed after a “killing frost.”
Fertile and infertile achenes set to disperse.

Photo 5

Frost flowers on Camphorweed.

Two other species of Pulchea are known from Arkansas: Pulchea odorata (sweetscent) and Pluchea foetida (stinking camphorweed).  Sweetscent differs from camphorweed in having inflorescence panicles strictly terminal or branching from only the upper nodes, elongated to nearly the level as the terminal panicle, giving the entire inflorescence a somewhat domed, flat-topped or layered appearance.  The flower heads of sweetscent are consistently deep rose-purple and the phyllaries are more densely hairy.  Sweetscent occurs in Arkansas primarily in the Coastal Plain and Arkansas River Valley, with a few scattered inland occurrences in the Ouachita Mountains along major rivers.  Stinking camphorweed differs from the previous two in having sessile, clasping leaves and flowers consistently light cream-colored.  It occurs in Arkansas exclusively in the Coastal Plain.  These two latter species can also produce frost flowers.

(For information regarding formation of frost flowers, see aKnow Your Natives” article posted November 26, 2013) link.

Article and Photos by ANPS member Sid Vogelpohl

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Know Your Natives – Great Plains and Fragrant ladies’-tresses orchids

Arkansas has 9 species of ladies’-tresses orchid in the genus Spiranthes. They are found across the state in a wide variety of habitats, from disturbed areas, lawns and roadside ditches to high quality meadows, marshes, prairies and woodlands.

Two of the more uncommon species in Arkansas are the Great Plains (S. magnicamporum) and fragrant (S. odorata) ladies’-tresses.

Great Plains Ladies'-tresses Orchid - Spiranthes magnicamporum

Great Plains ladies’-tresses orchid – Spiranthes magnicamporum

Great Plains ladies’-tresses are known from a few counties in southwestern Arkansas. It is found in high quality prairie habitat and blooms in the fall, typically around the middle of October, after the leaves have withered and disappeared. It is highly fragrant.

Fragrant ladies'-tresses orchid - Spiranthes odorata

fragrant ladies’-tresses orchid – Spiranthes odorata

Fragrant ladies’-tresses can be found widely scattered across Arkansas, but is absent from the most northern counties. It grows in wetlands and bogs, often in standing water. The basal leaves are generally present on blooming plants. It blooms in October and is also highly fragrant.

Article and photographs by ANPS member Eric Hunt

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Know Your Natives – Carolina Moonseed

Carolina Moonseed (Cocculus carolinus) of the Menispermaceae (Moonseed Family) occurs in the U.S. in the mid-western and southern states.  This semi-woody, scrambling or climbing vine occurs throughout Arkansas in shady to partly sunny woods and thickets and along streams and fence rows.  It is a slender twining vine without tendrils or thorns.  Carolina moonseed, a.k.a. Carolina snailseed, red-berried moonseed and Carolina coralbead, is usually deciduous, but can retain some smaller basal leaves into winter.

New and mature vines holding tightly to a small black cherry.

Young and mature vines holding tightly to a small black cherry.

Medium-green, slightly leathery leaves vary considerably in outline and size, but are generally ovate to heart-shaped to hastate (triangular) without lobes or with one to two broad lobes on either side.   Lobes of some leaves are so indistinct that the outline merely appears wavy.  Smaller leaves nearer ground-level tend to have more lobes or show a hastate shape while leaves higher in trees are significantly larger and almost oval.  Larger leaves may have blades 5.5” long and 6” wide with petioles of 4.5”.  Smaller leaves may have blades 2.75” long and 3.5” wide with petioles of 2.25”.  Leaf margins are entire with a pointed to rounded tip with tips typically having a needle-like point.  Leaf blades are sparsely covered with fine hairs.  Petioles are long and uniformly slender, with those of larger leaves tending to have a kink or bend (may be caused by leaves repositioning themselves during growth to access better sunlight).  Venation, as with leaf size, varies considerably, but remains palmate at the base.

Upper leaf surface of Carolina moonseed and ripe fruit.  (Leaves collected in November.  Petioles removed.)

Upper leaf surface of Carolina moonseed and ripe fruit.  (Leaves collected in November.  Petioles removed.)

Lower leaf surface of Carolina moonseed.  (same leaves as previous photo)

Lower leaf surface of Carolina moonseed. (same leaves as previous photo)

Carolina moonseed is dioecious (male and female flowers on separate plants).   Male panicles are up to 6” long while female clusters are much shorter.  Flowers may occur from near ground-level in fencerows to 40 or more feet up within trees.  Flowers, ¼” across, with white petals and green sepals occur in early summer.

Flowers on a male Carolina moonseed twinning around a blackberry stem.

Flowers on a male Carolina moonseed twining around a blackberry stem.

In late summer and early fall, tight to loose clusters of green fruit on the female vines mature to translucent brilliant red fruits (drupes) and become evident in fence rows and high-up in tall trees.  Fruit, persisting into late fall, are less than a fourth-inch in diameter and enclose a flattened, round, 1-seeded stone or pit about ⅛” in diameter and with a textured margin.  The stone is said to look like a crescent moon (thus, Carolina “moonseed”) or a snail (thus, Carolina “snailseed”).

Ripening clusters of Carolina moonseed on a vine dangling within a small pine.  Inset photo shows seed.

Clusters of ripening Carolina moonseed drupes on a vine dangling within a small pine. Inset photo shows the stones or pits of the fruits, each containing a single seed.

Carolina moonseed produces an abundance of fruit which are eaten by many bird species. It comes up from seeds readily.  Despite its showy leaves and fruit, the plant’s reputation for being difficult to control in garden settings suggests that it should not be planted in small or formal gardens, but rather should be appreciated in natural settings.

Note:  The related Canada moonseed (Menispermum canadense) occurs in moist forests in the highlands of northwest and central Arkansas.  Plant growth habit and leaves of Canada moonseed are similar to Carolina moonseed.  Canada moonseed can be distinguished by having petioles that join at the bottom surface of the leaf blade rather than at the margin.  Also, fruit of Canada moonseed (poisonous) resembles small-fruited, bluish-black grapes in color and cluster shape. A third member of this family in Arkansas, cupseed (Calycocarpum lyonii), also a vine, is found throughout the state, generally in rich, riparian forests.  Leaves of cupseed are often deeply three- to five-lobed, with generally long, slender, pointed tips.  The stones or pits of the bluish-black fruit of this species are oval, smooth and bowl-shaped or cupped (hence the name, “cupseed”).

Article and photos by ANPS member Sid Vogelpohl

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