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

	Sept/ Oct	Year to Date
Samples submitted by other DPI sections	1,676	7,977
Samples submitted for botanical identification only	122	603
Total Samples Submitted	1,798	8,580
Specimens added to the herbarium	108	437

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.

Hybanthus linearifolius (Vahl) Urban (chancleta), a genus of ca. 150 species in the tropics and subtropics of both hemispheres, with one species native to the eastern United States. Violaceae. Two genera of the Violet Family are native in Florida: Viola itself and the very different Hybanthus, with a single species, H. concolor (the green violet), occurring only in Gadsden County. Within the last decade, an exotic species of the latter genus, H. linearifolius, treated here, has made an appearance in South Florida and is now established and spreading. It is currently restricted to Miami-Dade and Palm Beach counties, with no indication that it will become a noxious weed, but it should be carefully monitored. It is an herbaceous perennial growing to 50 cm tall with oblong-lanceolate to linear-lanceolate, acute, short-petiolate leaves that are opposite in the upper portions of the stem, but alternate below. The odd flowers are usually borne singly on slender pedicels in the axils of the upper leaves. They are white or pale blue, from 5-8 mm long; the sepals and four of the petals are tiny and inconspicuous, but the fifth petal is enlarged and relatively prominent. Curiously, this largest petal rolls up lengthwise like a scroll as it ages. The plant is native to the West Indies. Its Puerto Rican name, “chancleta,” is the same as the word for “thongs” or “flip-flops,” those cheap sandals so popular nowadays. The flowers do bear a fanciful resemblance to tiny flip-flops. (Palm Beach County; B2009-555; Ellen J. Tannehill; 24 September 2009.) (Liogier 1994; http://www.florida.plantatlas.usf.edu.)

Plumeria pudica Jacq. (fiddle-leaf plumeria, bridal bouquet), a genus of 17 species native to tropical America. Apocynaceae. Plumeria is a genus of deservedly popular ornamentals, called “frangipani,” grown for their delicately colored, very fragrant flowers. The common ornamentals are mostly P. rubra and its cultivars. These are open, spreading trees with thick branches that regularly lose their leaves in dry or cold weather. The species treated here is very different from those described above in several important horticultural and technical aspects. It is mostly evergreen, with more slender but still fleshy branches, growing to 4 m tall with a dense, upright habit. The flowers are white, 5-7 cm across, with a yellow throat. They lack a sweet fragrance, but are borne profusely, and the blooming period extends through more than half of the year. In addition, the 12-25 cm long leaves have a very distinctive shape, termed pandurate (fiddle-shaped), with a lobe on each side above the middle, and then narrowing abruptly to the apex and tapering very gradually to the base. As with many other members of the Dogbane Family, a wound to any part of the plant produces a copious, thick, milky sap. Plumeria pudica is native to Panama, Colombia, and Venezuela and is frost-sensitive, succeeding as an ornamental only in the warmer parts of Florida. A form with variegated leaves is in cultivation, and recently a pink-flowered form has been introduced from Thailand. We have found no record of this species escaping from cultivation and becoming a weed anywhere to date. (Sarasota County; B2009-541; K. Lea Etchells; 22 September 2009.) (http://lee.ifas.ufl.edu/Hort/GardenPubsAZ/PlumeriaPudica.pdf.)

Schinus molle L. (Peruvian peppertree), a genus of 27 species distributed in tropical America. Anacardiaceae. Floridians are only too familiar with another species of Schinus, the Brazilian peppertree, S. terebinthifolius, which has become a destructive and almost uncontrollable weed in many parts of our state. S. molle is also a serious weed, particularly in South Africa and Australia, but not yet in the United States, although it is naturalized in California, Hawaii, Texas and Puerto Rico. The California Invasive Plant Council presently lists its statewide impact as “limited,” but there is concern that the impact could worsen. Peruvian peppertree is sparingly cultivated in Florida, and there is no report to date that it has naturalized here. Native to the drier parts of Andean South America, S. molle is tolerant of adverse soil and climatic conditions, particularly drought. It is a fast-growing tree, eventually reaching as much as 15 m tall, often with drooping branches. Its foliage is exceptionally airy and attractive. The evergreen leaves are alternate and pinnately compound, about 10-20 cm long, with 20-40 alternate, glossy, slender, long-acuminate leaflets. The leaflets are 2-5 cm long, seldom more than 7 mm wide, and often have indistinct serrations along the margin. Unlike the Brazilian peppertree, the rachis of the leaves is not winged. The small, cream-colored flowers are borne profusely in axillary and terminal panicles and are followed by conspicuous clusters of long-lasting red to pink or purplish drupes. The fruits have a peppery taste and are often mixed with true peppercorns to add color. The Incas used the berries to make fresh and alcoholic beverages. All in all, this is a handsome and useful plant. Unfortunately, it has the potential to become a serious pest and should be planted with caution. (Volusia County; B2009-558; Stacey S. Simmons; 6 October 2009.) (Mabberley 1997; http://en.wikipedia.org/wiki/Schinus_molle.)

Solidago species (goldenrods) are among the most readily identified wildflowers of the late summer and early fall. Their golden yellow inflorescences brighten roadsides, disturbed areas and waste places throughout all the United States (including one naturalized species in Hawaii) and Canada as well as in Mexico, Central America and even Eurasia where a few species are native. Recognizing the genus is fairly easy for observers driving 50 miles per hour; however, sorting out the species can be challenging. We have received several samples of Solidago for identification during the months of September and October, suggesting an interest in tips for separating these very similar fall beauties. All are perennials and have alternate, simple leaves and composite flowers with disc and ray florets. Characters such as the shape of the inflorescence, whether inflorescence branches are recurved (curve downward), whether flower heads are secund (with flowers on one-side of the branch), the change in the size of leaves from the base to the tip of the stem, leaf venation, and presence or absence of hairs on the leaves and stem are all important in separating these species. The table below, comparing several of these characters, includes species submitted for identification (indicated by an asterisk*) and other species commonly found in Florida.

Solidago species	Leaves appressed to stem	Leaf size upward from base of stem to apex	Leaf margin	Leaves with 3 main veins (tri-nerved)	Stem with hairs or glabrous	Inflorescence
S. canadensis*	no	only slightly smaller	usually serrate	yes	pubescent below inflorescence	paniculate, branches recurved, secund
S. leavenworthii	no	about the same size	serrate or entire	yes	glabrous	paniculate, branches recurved, secund
S. fistulosa	no	smaller, abruptly	few to many shallow teeth	no	covered with coarse, tangled hairs	paniculate, branches recurved, secund
S. odora*	no	smaller, gradually	entire	no	pubescent below inflorescence	paniculate, branches recurved, secund
S. sempervirens	yes	smaller, gradually from basal rosette	entire	no	glabrous	pyramidal or club-like, secund
S. stricta	yes	smaller, abruptly	entire	no	glabrous	elongate, wand-shaped, not secund
S. petiolaris*	no	about the same size	entire or with a few teeth	no	with short, fine pubescence	branches stiffly rising, not secund

Solidago canadensis L. (Canada goldenrod), a genus of about 80 mainly North American species. Compositae. Solidago canadensis grows from a rhizome, with a stem up to 2 m tall that is glabrous to about the midpoint then more or less covered with stiff, soft hairs up to the inflorescence. The tri-nerved, alternate leaves are narrowly ovate or elliptic and usually have serrate margins, but they can be entire. The abundant flower heads are held in one-sided pyramidal panicles with recurved branches. Each flower head usually has 8-14 ray florets and 3-6 disc florets, but larger and smaller numbers are possible. Although each ray is less than a millimeter long, the entire display of 150 or more heads is quite spectacular in the fall months. The dry fruit of the Compositae is a “cypsela,” an achene from an inferior ovary; for example, the edible sunflower seed. The cypsela of this species is 1-1.5 mm long. S. canadensis is the most common goldenrod species in the eastern United States. It has been used medicinally by indigenous people throughout its range and as a source of medicine, dyes and cordage by Europeans as well. (Alachua County; B2009-584; Paul Cohen; 19 October 2009.) (Austin 2004; Correll and Correll 1982; Hammer 2002; Mabberly 1997; www.enature.com/fieldguides; www.fna.org.)

Solidago odora Aiton (sweet goldenrod, anise-scented goldenrod), a genus of about 80 mainly North American species. Compositae. Solidago odora is most easily identified by the anise fragrance of its leaves when they are crushed. The stem, growing to a meter tall, is covered with a minute down or with the hairs growing in lines up to the base of the inflorescence. The basal leaves are oblanceolate with entire margins, while leaves along the stem are lanceolate to linear-lanceolate. Leaves near the inflorescence are much smaller than those at mid-stem. Unlike those of S. canadensis, the leaves of this species are not tri-nerved, a characteristic that helps distinguish the two quite similar species. The pyramidal paniculate inflorescences can contain over 300 heads, held on secund, recurved branches. Each flower has 3-4 (but sometimes 6) ray florets and 3-5 disc florets. The fruit is 1.4-2.3 mm long. This species is found in the eastern United States from New Hampshire to Texas including northern Florida and as far south as Volusia and Pasco counties. Sweet goldenrod has a long history of use by early residents of North America. During the Revolutionary War, colonists made a “Liberty Tea” from its leaves or flowers as a substitute for the taxable tea from China. This plant has also been used as a tonic and medicine for a range of conditions, including respiratory ailments and fevers. Some people continue to use the dried leaves for tea and young, green leaves are eaten as salad. (Sarasota County; B2009-509; K. Lea Etchells; 8 September 2009.) (Austin 2004; Clemants and Gracie 2006; Kunkle 1984; www.fna.org.)

Solidago petiolaris Aiton (downy ragged goldenrod), a genus of about 80 mainly North American species. Compositae. Although this species is clearly a goldenrod, it is quite different from the two Solidago species described above. The inflorescences are not recurved and one-sided, but have stiff ascending branches. This plant grows up to 1.5 m tall and has at least a few hairs on the stem. Leaves along the stem are somewhat variable: they can be either sessile or with a short petiole; either lanceolate or ovate; and have entire or slightly-toothed margins. The heads have leafy bracts that are similar in shape to the nearby leaves, but are much smaller. Each flower has 7-9 (but sometimes 5) ray florets and 10-16 disc florets. The ray florets are relatively large for goldenrods (3-7 mm long). The fruit is 3-4 mm long. Found only occasionally in North Florida, this goldenrod grows from North Carolina as far west as New Mexico and as far north as Illinois. Uses for S. petiolaris can be assumed to be those included in uses of the entire genus, for example, as a yellow dye or a medicinal tonic. Perhaps because Solidago species can be difficult to separate or because the species are interchangeable for many purposes, writers often lump uses for all the species under the generic name. (Alachua County; B2009-582; Claudia A. Larsen; 19 October 2009.) (Austin 2004; Wunderlin and Hansen 2003; www.fna.org; www.missouriplants.com.)

References

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

Clemants, S.E. and C.A. Gracie. 2006. Wildflowers in the field and forest. Oxford University Press, New York, NY. 445 p.

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

Hammer, R.L. 2002. Everglades wildflowers. Falcon Press, Guilford, Connecticut. 231 p.

Kunkel, G. 1984. Plants for human consumption. Koeltz Scientific Books, Koenigstein, Germany. 393 p.

Liogier, H.A. 1994. Descriptive flora of Puerto Rico and adjacent islands. Violaceae: 251 – 256.

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