FDACS DPI Tri-ology March - April 2009: Botany Section

	May/ Jun	Year to Date
Samples submitted by other DPI sections	1,934	4,569
Samples submitted for botanical identification only	138	332
Total Samples Submitted	2,072	4,901
Specimens added to the herbarium	88	218

Botany Section

Compiled by Richard E. Weaver, Jr., Ph.D., and Patti J. Anderson, Ph.D.

This section identifies plants for the Division of Plant Industry, as well as for other governmental agencies and private individuals. The Botany Section maintains a reference herbarium with over 10,000 plants and nearly 1,400 vials of seeds.

Asclepias cinerea Walt. (Carolina milkweed) (a genus of about 100 species primarily from North and Central America, with some naturalized in the Old World). Asclepiadaceae. Found mainly in dry pinelands from South Carolina to Florida and west to Mississippi, this perennial herb with milky sap has slender, glabrous stems (although they are sometimes marked with a vertical band of pubescence) to 30 cm tall, growing from woody or tuberous roots. The leaves are opposite, narrowly linear and up to 10 cm long. The flowers are loosely held in umbels on lax, 1.5 – 2.5 cm long pedicels. The calyx has five connate, lanceolate lobes; the corolla has reflexed lobes that are lavender or lavender with white margins or bases. As is characteristic of Asclepias, the five stamens, with two pollinia per anther, are fused to the stigma to form a gynostegium with unusual floral appendages: a spur-like horn surrounded by a cup-like hood. In this species, the lavender hoods are shorter than the gynostegium and have a pair of triangular, 1 mm long lobes on the margin. The fruit is a slender follicle that narrows toward both tips, about 8 cm long and 5-6 mm wide. The genus Asclepias was named for the Greek mythological god of physicians and healing, Asklepios. Not surprisingly, the species within this genus have been used medicinally, both by Native Americans and Europeans, for respiratory, digestive and skin ailments. Unfortunately, the chemicals produced by these plants, including alkaloids and cardiac glycocides, are considered dangerous and not recommended for internal and external use. Carolina milkweed is native to Florida and occurs across North Florida, as far south as Marion County. (Duval County; B2009-288; Flewellyn W. Podris; 25 June 2009.) (Austin 2004; Godfrey and Wooten 1981; Wunderlin and Hansen 2003; http://www.florida.plantatlas.usf.edu.)

Camptotheca acuminata Decne. (Happy tree, camptotheca) (a genus of two species restricted in distribution to southern and western China). Nyssaceae (or Cornaceae). This handsome tree is often planted along streets in its native China, but it is rare in cultivation in this country. In the wild, it is relatively fast-growing and attains a height of 20 m. This species is closely related to our native black gums and tupelos (Nyssa spp.). Its leaves resemble those of Nyssa ogeche, except that they are broader with more prominent lateral veins. The leaf blades are 12-28 cm long and 6-12 cm broad, mostly elliptical, rounded at the base and sharp-pointed at the apex. The leaves are entire along the margin and have 8-11 pairs of veins. Male and female flowers are generally borne in separate inflorescences on the same tree, but most individuals produce some bisexual flowers as well. The flowers are borne in open clusters of long-stalked, ball-like heads that are 1.5-2 cm in diameter. The petals and sepals are greenish and inconspicuous, but the protruding stamens make the male-flowered heads quite showy. The narrowly winged fruits are also borne in globose heads as much as 7 cm in diameter. In addition to its ornamental aspects, this tree has medicinal properties as well. The alkaloid camptothecin, extracted from the bark, is a powerful anticancer drug. Unfortunately, it is toxic to human cells in general and thus is of limited utility. However, several less toxic derivatives have been approved for use in cancer therapy. (Orange County; B2009-323; George A. Warden, 16 June 2009.) (Qin and Phengklai 2007; http://botany.csdl.tamu.edu/FLORA/gallery.htm.)

Fraxinus (Ash tree) (a genus of 65 north temperate species with a few extending to the tropics). Oleaceae. We have received numerous specimens of this genus for identification recently due to a concern for a wood boring beetle not yet known to occur in Florida. Two from the current period are included below. The four species of Fraxinus native to Florida can be difficult to separate because they share many common characteristics, such as opposite compound leaves, and the size of some characteristics overlap among the species. In addition, some morphological characteristics vary with ecological factors. The shape and size of leaves and leaflets fluctuate so much that samaras are usually required to confirm the species identity. Species also hybridize, making identification even more challenging. To illustrate the differences and similarities, a table of characteristics that might be useful for separating the species is provided below. The Florida ashes are all deciduous, with opposite, odd-pinnately compound leaves, and inconspicuous male and female flowers on separate trees. The male (staminate) flowers have a calyx and two stamens; female (carpellate) flowers have a calyx, no petals and a pistil. The calyx is often persistent on the samaras (winged fruits) produced only on trees with carpellate flowers. These wind-pollinated flowers are held in dense inflorescences and mature before the leaves of the tree emerge in spring. Samaras persist on the trees for much of the growing season. The single seed enclosed in each of the samaras is usually round in cross-section, except for the flattened seeds of Fraxinus caroliniana. Although some authorities include Fraxinus profunda (formerly Fraxinus tomentosa) within Fraxinus pennsylvanica, we now recognize them as separate species. Any of the ash species in Florida could become a host for the emerald ash borer, Agrilus planipennis Fairmaire, an exotic beetle that is establishing populations in several states, with recent introductions into Kentucky and Virginia. A pest alert, available from the DPI website, provides more information about the insect.

Fraxinus species comparison (based on Godfrey 1988; Kurz and Godfrey 1993; Wallander 2008) Note: The characteristics described below, including habitat and growth form, may be helpful when used together to identify a species, although the variability within and among the species makes identification difficult.
	F. americana	F. caroliniana	F. pennsylvanica	F. profunda
Habitat	Well-drained forests or occasionally wet areas	Wetland species in swamps and wet forests	Wetland species in swamps and wet forests	Wetland species in swamps and wet forests
Growth form	Single stem tree 25-35 m tall	Often multi-stemmed tree 10-12 m tall	Single stem tree 30 m tall	Single stem tree 30 m tall
Leaves	20-30 cm long odd-pinnately compound with 5-9 leaflets (usually 7)	15-30 cm long odd-pinnately compound with 5-7 leaflets (rarely 3 or 9)	20-30 cm long odd-pinnately compound with 5-9 leaflets (usually 7)	12-30 cm long odd-pinnately compound with 5-9 leaflets (usually 7)
Lateral leaflet stalk (petiolule)	0.5-1.5cm long	0.5-2 cm long	0.5-1 cm long	0.5-2.5cm long (rarely to 4 cm)
Leaflet upper surface	Green, glabrous	Green, glabrous	Dark green, glabrous	Dark green, glabrous
Leaflet lower surface	Whitish; pubescent along veins or the entire surface	Paler green; glabrous or short pubescent along the midrib	Paler, duller green; glabrous or pubescent with short and not tangled hairs in a band along the midrib or with hairs over the whole surface	Paler, yellowish-green; pubescent in an irregular band of tangled hairs along the midrib or with hairs over the whole surface, more densely along the midrib
Fruit	Samara, 2.5-6.5 cm long, wing not extending downward along the seed-bearing portion	Samara, 2-5 cm long, wing extending downward to the base of the seed-bearing portion; occasional 3-winged fruits	Samara, 3-6 cm long, wing extending at least halfway downward along the seed-bearing portion	Samara, 4-8 cm long, usually with a notch at the tip, wing merging with the seed-bearing portion and tapering to the base of the seed
Seed	Rounded	Flat (or concave)	Rounded	Rounded

Fraxinus caroliniana Mill. (Carolina ash, pop ash) (a genus of 65 north temperate species with a few extending to the tropics). Oleaceae. Found mainly in the coastal plain from Virginia southward to Florida and as far as Texas to the west, this species grows nearly throughout Florida, in the understories of wet areas such as swamps and hydric hammocks. It is the smallest of our ashes and is often multi-stemmed. The base of the tree sometimes widens to form a buttress which adds stability in wet soil. The leaves of this species vary greatly in overall size and in leaflet shape. The margins may be entire, serrate or crenate. The very variable samaras may be linear-elliptical to suborbicular, spatulate, ovate or oblong and sometimes have three wings. Because it is relatively small, grows in swampy forests and has light-weight wood, this species is seldom used for timber or other purposes. The pop ash is sometimes planted on the borders of retention ponds and in wetland restoration projects, but is not often used as a landscape tree. (Marion County; B2009-280; Adam J. Silagyi, USDA-CAPS, and Leroy A. Whilby, DPI-CAPS; 3 June 2009.) (Godfrey 1988; Mabberley 1997; Wunderlin and Hansen 2003; http://www.plantatlas.usf.edu)

Fraxinus profunda (Bush) Bush (Pumpkin ash) (a genus of 65 north temperate species with a few extending to the tropics). Oleaceae. This species is found scattered from New York to southern Illinois southward to Florida and Louisiana, but in Florida only as far south as Marion County. Pumpkin ash grows in wet places, and the base of the tree forms buttresses in frequently flooded areas. This enlargement of the trunk is said to look like a pumpkin and may have led to the common name. The leaves of this species usually consist of seven leaflets on fairly long petiolules. As with other species, this one has variable leaflet shapes, but the margins are usually entire although they sometimes have irregular serration. The lower surface of the leaflets is distinguished by tangled, tawny hairs that are especially dense along the midrib and lateral veins, but may cover much of the lamina. The upper surface of the leaflets is dark green and glabrous. The samara often has a tiny notch at the tip and may be spatulate to oblong to oblanceolate. The samara wing distinguishes this species by merging with the seed-bearing portion and tapering downward to the base of the rounded seed. The wood is similar to that of other ash trees. Because this species has sometimes been included with F. pennsylvanica, many uses reported for either species may be assumed to be possible for both, including use for lumber and to make wooden handles, bowls and other small utensils. (Jackson County; B2009-236; Shi-Yih “Edward” Hung and Leroy A. Whilby, DPI-CAPS; 21 May 2009.) (Austin 2004; Godfrey 1988; Wallander 2008; http://www.carolinanature.com.)

Sacoila lanceolata (Aubl.) Garay. (Beaked ladiestresses) (a genus of 10 species in tropical and subtropical areas of the Americas). Orchidaceae. This conspicuous and widespread species, also known as Spiranthes lanceolata and Stenorrhynchos lanceolatus, is one of Florida’s showiest terrestrial orchids. It ranges from Florida and the West Indies, through Mexico and Central America, to South America east of the Andes as far south as Uruguay. In Florida, it is occasionally seen in flatwoods, oak hammocks, pastures, and roadsides throughout most of the peninsula, with an isolated station in Walton County in the Panhandle. The basal rosette of four to six fleshy leaves grows from a cluster of unbranched, thick, tuberous roots. The leaves are about 15-35 cm long. They appear in early summer after the blooms have faded, then disintegrate during the winter, and are at no time present with the flowers. The spikes appear from April to July, depending on location and environmental conditions, and elongate rapidly to as much as 40 cm tall, bearing 25-40 flowers in the upper third. The flowers vary in color from coral pink to brick red, with a protruding white or pinkish lip, and measure two to three cm in length. Two varieties of this species are present in Florida. The typical variety, lanceolata, the leafless beaked ladiestreses, is described above. The var. paludicola, the leafy beaked ladiestresses, is found only in Broward, Collier, Miami-Dade and Sarasota counties. This latter differs from the typical variety most noticeably in its deep red flowers and in having leaves present at flowering time; some authorities consider it a separate species, Sacoila paludicola. The species, including both varieties, is included on the list of threatened plants by the State of Florida in order to draw attention to its vulnerability, although it is by no means rare at the moment. It is easily cultivated in the garden or in containers, and nursery-propagated plants are often available. (Okeechobee County; B2009-300; Christine J. Frere, 9 June 2009.) (Luer 1972; http://www.plantatlas.usf.edu.)

Sclerochiton harveyanus Nees. (Blue lips) (a genus of 19 species native to tropical and southern Africa). Acanthaceae. This native of wet montane forests in southeastern Africa, from Mozambique to South Africa, is extremely rare in cultivation, and it proved difficult to positively identify. Because of its unusual corolla, we first assumed that it was a species of Scaevola, the fanflowers or half-flowers. But its opposite leaves, superior ovary and only four stamens, with anthers consisting of a single sac, pointed to the Acanthus family instead. This species forms a slender-stemmed, often straggling shrub to 3 m tall in the wild. The 3-6 cm long leaves are elliptical, with entire or sparsely but coarsely toothed margins. The flowers are borne singly or in small clusters in the axils of the uppermost leaves. As mentioned earlier, they superficially resemble the flowers of Scaevola in the Goodenia family. The corolla consists of a tube with five lobes, but the tube is contorted so that the lobes are all on the lower part of the flower, forming a single fan-like lip. This lip, held almost horizontally, is blue to purple in color and 13-18 mm long. Because the plant is evidently a sparse bloomer and the flowers are on the small side, it is not remarkably showy. But its rarity and unusual flowers make it well worthy of cultivation. (Pinellas County; B2009-303; Thomas L. Lastrapes, 3 June 2009.) (Volleson 1991; http://www.zimbabweflora.co.zw.)

References

Austin, D.F. 2004. Florida ethnobotany. CRC Press, Boca Raton, Florida. 909 p.

Godfrey, R.K. 1988. Trees, shrubs and woody vines of northern Florida and adjacent Georgia and Alabama. University of Georgia Press, Athens, Georgia. 735 p.

Godfrey, R.K. and J.W.Wooten. 1981. Aquatic and wetland plants of southeastern United States: dicotyledons. University of Georgia Press, Athens, Georgia. 933 p.

Luer, C.A. 1972. The native orchids of Florida. The New York Botanical Garden, Bronx, New York. 293 p.

Mabberley, D.J. 1997. The plant book, 2nd edition. Cambridge University Press, Cambridge, England. 858 p.

Qin, H. and C. Phengklai. 2007. Nyssaceae in Flora of China 13: 300-303.

Volleson, K. 1991. A revision of the African genus Sclerochiton (Acanthaceae: Acantheae). Kew Bulletin 46: 1-50.

Wallander, E. 2008. Systematics of Fraxinus (Oleaceae) and evolution of dioecy. Plant Systematics and Evolution 273: 25-49.

Wunderlin, R. P. and B. F. Hansen. 2003.Guide to the vascular plants of Florida, 2nd edition. University Press of Florida, Gainesville, Florida. 787 p.

Sample Submissions

Botany Section

References