FDACS DPI Tri-ology September - October 2009: Botany Section

	Nov/ Dec	Year to Date
Samples Submitted by Other DPI Sections	1,175	9,152
Samples Submitted for Botanical Identification Only	94	697
Total Samples Submitted	1,269	9,849
Specimens Added to the Herbarium	70	507

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.

Cardiospermum microcarpum Kunth (heartseed), a genus of 14 tropical and subtropical species. Sapindaceae. In Florida, heartseed is found in scattered counties from the Keys to Marion County in the north. The collection deposited in DPI’s herbarium is the first vouchered specimen for Alachua County. The perennial, herbaceous vine climbs with tendrils and grows in a number of habitats, including moist woods, coastal shell mounds, roadsides and wasteplaces. The grooved stem can grow as long as 3 m. The bipinnate leaves are alternate, and the ovate leaflets have deeply incised margins. The tiny (2-3 mm) greenish-white flowers are held in axillary cymes with a pair of bracts modified into tendrils subtending them. The fruit is an inflated, subglobose, tri-lobed capsule, about 1 cm long, containing three small, black seeds, each with a white, heart-shaped spot that inspired the common name. Another species in this genus, C. halicacabum, with slightly larger flowers and fruit and an even more whimsical name, is called “love-in-a-puff.” Members of this plant family often have dark (brown to black) seeds with pale hylar scars, marking the point at which the seed was attached in the fruit. Having a heart-shaped scar has made C. microcarpum and others in this genus valued as aphrodisiacs, or at least as jewelry beads, but some people focus on the interesting inflated fruit and call either species “balloon vine.” The fruit of this vine can add interest to a garden, and some people eat the cooked leaves like spinach. This species has a wide-range of medical uses, including as an analgesic, a diuretic, and of course, as a treatment for ailments of the heart. (Alachua County; Herbarium Accession 10,749; Richard E. Weaver, DPI; 28 October 2009 and Alachua County; B2009-703; Scott Flamand, Buchholz High School and Andrea N. Christman, DEP; 20 December 2009.) (Austin 2004; Correll and Correll 1982; Hammer 2004; Mabberly 1997; www.eflora.org.)

Chromolaena odorata (L.) R. M. King & H. Robinson (Jack-in-the-bush, Siam weed, Christmas bush), a genus of 165 species native to tropical and subtropical areas of the Americas; sometimes included in Eupatorium. Compositae/Asteraceae. This weedy species is native from Texas and Florida south throughout most of tropical America, but it has become naturalized widely in the Old World tropics as well. In Florida, it is common along hammock borders, on shell middens and in disturbed areas such as fields and roadsides in the southern peninsula, as well as in Polk and Hillsborough counties in the central part of the state. It is a thicket-forming, often scandent shrub, seldom more than 3 m tall when free-standing, but climbing to as much as 7 m when supported. The opposite, three-nerved, hairy or glabrous leaves are ovate to triangular with an acuminate apex, a broadly truncate base, and a coarsely toothed margin. They are usually 8-13 cm long and 5-8 cm broad and have a medicinal odor when crushed. The cylindrical flower heads are about 1 cm long and are arranged in terminal and axillary, flat-topped clusters; they consist entirely of white, pale blue or pale lavender disc florets. The achenes are crowned with a pappus of finely barbed bristles, allowing them to be dispersed widely by the wind. Having wind-dispersed propagules is a characteristic of many weedy plants, and this one is no exception. The Jack-in-the-bush is a serious weed of 13 crops in more than 20 countries, from oil palms and tobacco in Malaysia to rubber, tea, teak and vegetables in India. On the other hand, it has proved an efficacious green manure in cassava cultivation and a nematode control in black pepper. (Miami-Dade County; B2009-707; Maria C. Acosta; 29 December 2009.) (Holm et al. 1977; www.florida.plantatlas.usf.edu.)

Chrysoma pauciflosculosa (Michx.) Greene (woody goldenrod), a monospecific genus found in the southeastern United States. Compositae/Asteraceae. This species was once included with others we call “goldenrods,” in the genus Solidago, but Chrysoma pauciflosculosa is different from the Solidago goldenrods in that it has a woody stem and shrubby growth habit and its leaves have a striking reticulate venation. These resinous, evergreen, up to 1 m tall shrubs, have leaf adaptations to conserve water and tolerate a salty habitat and are found near coastal dunes and in sandhill and scrub communities from Mississippi to North Carolina. In Florida, the species is restricted to the Panhandle where it is found in coastal counties from Escambia to Wakulla. The sessile, gray-green leaves with entire margins are alternate, oblanceolate to elliptic, and up to 6 cm long and 1.2 cm wide. The midvein is prominent on the underside of the leaf blade, but not on the upperside. The viscid inflorescence is a corymbiform array with cylindric involucres 2–2.5 mm long. The one to three fertile, pistillate ray florets have yellow corollas. The fertile, bisexual disc florets also have yellow corollas. The fruit, to 3 mm long, is a tan to brownish ribbed achene with a ring of 4-5 mm long bristles at the apex. This species flowers from late summer through autumn about the same time as “true” goldenrods. (Franklin County; B2009-639; Olga Garcia; 7 November 2009.) (Anderson and Creech 1975; Godfrey 1988; Lloyd 1901; www.eflora.org.)

Garberia heterophylla (W.Bartram) Merr. & F.Harper (garberia), a monospecific genus found in Florida. Compositae/Asteraceae. This species is also a plant found in Florida scrub communities, but it is even more restricted geographically than Chrysoma pauciflosculosa (above). Garberia is endemic to peninsular Florida and has been documented in to grow from Clay County as far south as Highlands County, and from Brevard County as far west as Pinellas County. The more or less evergreen shrub can reach 2.5 m in height. The somewhat fleshy leaves are alternate (usually) and lack noticeable venation. The leaf blades, up to 3 cm long and 2 cm wide with rounded to somewhat retuse tips, are dotted with glands, have entire margins and are gray-green in color. Inflorescences of this species are flattened corymbs with heads of disc florets with pinkish, purple or occasionally white, 8-10 mm long corollas. The achene is about 7–8 mm long with 8-10 mm long bristles. Garberia’s ability both to resprout and to produce increased numbers of seedlings after fire makes the species well-adapted to the fire-maintained scrub in which it is found, yet this endemic is listed as threatened by the state. Concern for its future is based on the very limited area in which it grows and the potential for habitat loss within that area. The striking flowers of this species remind some observers of Liatris, another purple, fall-blooming composite found in dry sandhills, and the two are closely related. This beautiful plant would be a welcome addition to xeriscapes and butterfly gardens. (Hillsborough County; B2009-647; Susan B. Youngblood; 13 November 2009; and Pinellas County; B2009-655; Linda G. McRay; 17 November 2009.) (Carrington 1999; Godfrey 1988; Wunderlin and Hansen 2003.)

Oeceoclades maculata (Lindl.) Lindl. (monk orchid), a genus of 31 species mostly distributed in tropical Africa and the Indian Ocean islands, with a single species in the American tropics. Orchidaceae. This attractive plant is one of the few weedy orchid species. In fact, for several years, it was listed as an invasive by the Florida Exotic Pest Plant Council (FLEPPC), but it has since been reevaluated and delisted. It is native throughout the tropics of Africa and the Americas, and its range in the latter area is expanding rapidly. It was first discovered in Puerto Rico in the 1960s and is now found throughout the island. Likewise in Florida, it was first discovered in 1974 in Miami-Dade County, either an escape from cultivation or a natural colonization from the Bahamas. The plant is now known from 14 counties, mostly in the central and southern parts of the state. A record from Alachua County is surprising, because the plant is quite frost-sensitive. The orchid forms small clumps of slightly compressed pseudobulbs, each bearing a single, decorative, leathery leaf that is olive green with dark green mottling, and usually 15-20 cm long. The erect scape is about 15-30 cm tall, with 5-15 flowers opening in succession. The flowers are reminiscent of a miniature cymbidium, but only 10-15 mm across, with greenish or brownish sepals and petals, and a pink and white lip. The flowers often self-pollinate, so seed set is high, and the distinctive capsules have conspicuous, sharp ridges. The monk orchid is occasionally cultivated for its attractive foliage and its charming but not showy flowers. It is not difficult to grow in containers as long as it is not overwatered. In central and southern Florida, it can be enjoyed in the garden, where it does best in full to partial shade and well-drained soil. (Miami-Dade County; B2009-660; Olga Garcia; 23 November 2009.) (Ackerman 1995; Hammer 2002; www.flmnh.ufl.edu/herbarium.)

Tithonia diversifolia (Hemsl.) A. Gray (Mexican sunflower), a genus of 11 species native from the southwestern United States through Mexico into Central America. Compositae/Asteraceae. This spectacular plant is a close relative of Tithonia rotundifolia, a popular annual bedding plant with the same common name, but T. diversifolia is a towering, clump-forming perennial, capable of growing as much as 5 m tall in a single season. The alternate leaves are coarse and rough-hairy, with three to five long-acuminate, coarsely serrate lobes and a base that tapers to a winged petiole. The leaves vary greatly in length from 15-35 cm long. The flower heads are borne singly or in small clusters. They resemble those of the true sunflowers (Helianthus), with 10-13 golden yellow rays and a greenish yellow disc. With a diameter to 15 cm, they are very showy. The plant is native to Mexico and Central America, but it is widely planted throughout the tropics and has become weedy in spots. It has naturalized in nine counties in central and southern Florida, where some fear that it might become invasive. The flowers and foliage of the Mexican sunflower are often damaged by even a light frost, and the plant is killed to the ground by freezing temperatures. Since it blooms in the late fall in northern Florida, the floral display is usually truncated by cold, and seeds are seldom produced; however, the roots will survive temperatures into the low twenties F. It is easily cultivated, but it requires full sun to produce the best bloom and to keep it standing erect. (Escambia County; B2009-633; W.L. Robinson; 6 November 2009.) (www.floridata.com.)

References

Ackerman, J.D. 1995. An orchid flora of Puerto Rico and the Virgin Islands. Memoirs of the New York Botanical Garden 73: 1-203.

Anderson, L.C. and J. B. Creech. 1975. Comparative leaf anatomy of Solidago and related Asteraceae. American Journal of Botany 62: 486-493.

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

Carrington, M.E. 1999. Post-fire seedling establishment in Florida sand pine scrub. Journal of Vegetation Science 10: 403-412.

Correll, D.S. and H.B. Correll. 1982. Flora of the Bahama Archipelago. J. Cramer, Hirschberg, Germany. 1,692 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.

Hammer, R.L. 2002. Oeceoclades. Flora of North America 26: 640-641.

Hammer, R.L. 2004. Florida Keys wildflowers: a field guide to wildflowers, trees, shrubs, and woody vines of the Florida Keys. Falcon Press, Guilford, Connecticut. 231 p.

Holm, L.G., D.L. Plucknett, J.V. Pancho and J.P. Herberger. 1977. The world’s worst weeds. The University Press of Hawaii, Honolulu, Hawaii. 609 p.

Lloyd, F.E. 1901. Some points in the anatomy of Chrysoma pauciflosculosa. Bulletin of the Torrey Botanical Club 28: 445–450.

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

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