Cirsium lecontei

Circsium lecontei Le Conte's thistle
Scientific classification
Kingdom:	Plantae
Division:	Magnoliophyta
(unranked):	Dicot
Class:	Magnoliopsida
Order:	Asterales
Family:	Asteraceae
Genus:	Cirsium
Species:	C. lecontei
Binomial name
Cirsium lecontei Torr. & Gray[1]

Cirsium lecontei (often called the Le Conte's thistle) is a species of thistle that is part of the Asteraceae family. Cirsium lecontei is a forb/herb of the genus Cirsium. A forb/herb is a non-woody plant that is not a grass.^[2] It’s duration is perennial, which means it will grow year after year. It sometimes appears biennial. They flower spring to summer (May-Aug). ^[3]

Description

They grow to be 35-110 cm and have taproots, sometimes with root sprouts.^[4] The plant has spines or sharp edges and should be handled with extreme caution. When they bloom, they are usually pale pink or pink in color. Full sun exposure is needed in order for growth to take place. Le Conte's Thistle has a National Wetland Indicator Status of FACW-usually occurs in wetlands. ^[5] The stems are loosely arachnoid and stiffly ascending. Leaves have blades that are linear to oblong or narrowly elliptic, loosely arachnoid when young, abaxial and adaxial faces glabrous(smooth), and lobes undivided or coarsely few toothed. Basal leaves sometimes absent at flowering, petiolate. Heads born singly or 2–5 or 10 in open, corymbiform arrays. Penduncles are 5-30 cm elevated above cauline leaves. Cypselae is light brown in color, 5-5.75mm.^[6] Plants are often unbranched or sparingly branched, with single terminal flower heads that are above the foliage(plant leaves). Stem and lower leaf surfaces have cob webby hairs. With age, the plant starts losing the hairs and becoming glabrous(hairless,smooth). Leaves of the mid-stem are approximately 15 cm long, the leaves gradually reduce in size up the stem, and are pinnately lobed. Corollas have feather-like pappus bristles (modified sepals) that are pinkish/purple in color.^[7]

Distribution

Cirsium lecontei or Le Conte's thistle's floral region is native in North America. They occur on the sandy pinelands of southern coastal plain in damp soil(where co-occurring species include Myrica, Cyrilla, and Ilex), specifically in the states of Alabama, Florida, Georgia, Louisiana, Mississippi, North Carolina and South Carolina. ^[8] They are also found in moist to wet grassy pine savannahs and pine barrens, bogs(other species present include pitcher plants, Ilex, sedges, grasses, and sphagnum), and roadside ditches.^[9]

Threats

Cirsium lecontei occurs mostly in North Carolina but even there it appears to be rare. It's presence is also rare from South Carolina south to Florida and west to Louisiana. Thus, populations tend to be very small and can be as small as one individual.^[10] The probable cause decreasing presence of these species are conversion of habitat to pine plantation which may include site prep activities (such as bedding and herbicides),inappropriate fire timing, and commercial and residential development.^[11]

Hypotheses

R.J.Moore and C. Frankton(1969) suggested that it originated as a product of ancient hybridizaton between the ancestors of C. horridulum and C. nuttallii. They also suggested a relationship between C. lecontei and C. grahamii of Arizona and hypothesized an ancient dispersal from the southeastern coastal plain to western cordillera. ^[12]

References

1. ^ http://www.invasive.org/browse/subinfo.cfm?sub=12917
2. ^ plant databade plantdatabase-cirsium lecontei
3. ^ Keil, David J. & Ochsmann, J. (2006): 24. Cirsium lecontei. In: Flora of North America North of Mexico Vol. 19 (Magnoliophyta: Asteridae, part 6: Asteraceae, part 1). Oxford University Press. ISBN 0195305639 HTML fulltext
4. ^ Keil, David J. & Ochsmann, J. (2006): 24. Cirsium lecontei. In: Flora of North America North of Mexico Vol. 19 (Magnoliophyta: Asteridae, part 6: Asteraceae, part 1). Oxford University Press. ISBN 0195305639 HTML fulltext
5. ^ davesgarden-Le Contes thistle
6. ^ Keil, David J. & Ochsmann, J. (2006): 24. Cirsium lecontei. In: Flora of North America North of Mexico Vol. 19 (Magnoliophyta: Asteridae, part 6: Asteraceae, part 1). Oxford University Press. ISBN 0195305639 HTML fulltext
7. ^ googledoc-cirsium lecontei
8. ^ Keil, David J. & Ochsmann, J. (2006): 24. Cirsium lecontei. In: Flora of North America North of Mexico Vol. 19 (Magnoliophyta: Asteridae, part 6: Asteraceae, part 1). Oxford University Press. ISBN 0195305639 HTML fulltext
9. ^ naturereserve-LeContes thistle
10. ^ naturereserve-LeContes thistle
11. ^ googledoc-cirsium lecontei
12. ^ Keil, David J. & Ochsmann, J. (2006): 24. Cirsium lecontei. In: Flora of North America North of Mexico Vol. 19 (Magnoliophyta: Asteridae, part 6: Asteraceae, part 1). Oxford University Press. ISBN 0195305639 HTML fulltext