Seymeria cassioides

Seymeria cassioides
Photo was taken by Gil Nelson
Scientific classification
Kingdom:	Plantae
Division:	Magnoliophyta – Flowering plants
Class:	Magnoliopsida – Dicotyledons
Order:	Scrophulariales
Family:	Scrophulariaceae
Genus:	Seymeria
Species:	S. cassioides
Binomial name
Seymeria cassioides (J.F. Gmel.) S.F. Blake
Natural range of Seymeria cassioides from USDA NRCS Plants Database.

Common names: Yaupon blacksenna or Senna seymeria (Nelson 2005).

Description

It is an annual, herbaceous root parasite on several species of southern pine but produces most of its own food (Crow and Shilling 1980; Fitzgerald et al. 1977). It can grow about one meter tall and is covered in gladular hairs. Flowers are bright yellow with brown marks near the ovary and have a small pore anther opening instead of a long slit (Musselman and Mann 1978).

"Erect, often profusely branched, presumably parasitic, glandular-pubescent annuals. Leaves opposite, pinnately or bipinnately parted or divided into linear to filiform segments. Flowers axillary, solitary, the terminal racemes weakly differentiated. Calyx lobes 5, longer than the tube; corolla yellow, rotate, 9-10 mm long, nearly regular, the lobes 5, longer than the tube; stamens 4, exserted, filaments pubescent. Capsule ovoid, 4-6 mm long; seeds numerous, winged." - Radford et al 1964

"Plant profusely branched, the branches ascending, stem pubescence short, antrorse. Leaves mostly less than 1 cm long, segments filiform, less than 0.5 mm wide. Calyx lobes linear, 1.5-2.5 mm long. Capsule glabrous." - Radford et al 1964

Ecology

Habitat

In the Coastal Plain region, S. cassioides can be found in wet to mesic pine flatwoods, wet savannas, seepage slopes, and ectones between pine flatwoods and cypress/titi swamps (FSU Herbarium; Kral 1983, USFWS 1992). It has been recorded to grow in loamy sand, red clay and poorly drained areas (FSU Herbarium). It is one of the most serious native parasites (Musselman 1996). Associated species include Pinus, Cypress, and Cyrilla (FSU Herbarium).

Phenology

It blooms from September to October (Nelson 2005) with each flower only lasting for one day (Musselman and Mann 1978).

Seed dispersal

According to Kay Kirkman, a plant ecologist, this species disperses by wind.

Seed bank and germination

It requires exposed mineral soil and light on the soil surface to germinate (Stangle 1981; Wade 1978). One plant can produce up to 150,000 seeds (Grelen and Mann 1973).

Fire ecology

It often reproduces profusely after fire because it has the ability to reproduce quickly on open ground (Crow and Shilling 1980). Thus, the best way to control S. cassioides may be to implement a prescribed burn after seeds germinate in the spring, but before flowers appear (Grelen and Mann 1973).

Cultivation and restoration

Plantations appear to be at a higher risk of high Seymeria populations than natural stands because of the greater area of exposed soil in the early years of establishment and the frequent use of fuel reduction burns (Fitzgerald et al. 1977).

References and notes

Crow, A. B. and C. L. Shilling. 1980. Use of prescribed burning to enhance southern pine timber production. Southern Journal of Applied Forestry 4:15-18.

Fitzgerald, C. H., R. C. Schultz, J. C. Fortson and S. Terrell. 1977. Effects of seymeria cassioides infestation on pine seedling and sapling growth. Southern Journal of Applied Forestry 1:26-30.

Florida State University Robert K. Godfrey Herbarium database. URL: http://herbarium.bio.fsu.edu. Last accessed: July 2015. Collectors: Loran C. Anderson, Wilson Baker, R. Komarek, Leon Neel, T. MacClendon, Boothes, Robert K. Godfrey. States and Counties: Florida: Franklin, Jackson, Liberty, Wakulla. Georgia: Thomas. Compiled by Tall Timbers Research Station and Land Conservancy.

Grelen, H. E. and W. F. Mann. 1973. Distribution of Senna seymeria (Seymeria cassioides) a root parasite on southern pines. Economic Botany 27:339-342.

Musselman, Lytton J. "Parasitic Weeds in the Southern United States."Castanea 61.3 (1996): 271-92. Web.

Musselman, Lytton J., and William F. Mann, Jr. "Root Parasites of Southern Forests." Southern Forest Experiment Station (1978).

Nelson, Gil. East Gulf Coastal Plain. a Field Guide to the Wildflowers of the East Gulf Coastal Plain, including Southwest Georgia, Northwest Florida, Southern Alabama, Southern Mississippi, and Parts of Southeastern Louisiana. Guilford, CT: Falcon, 2005. 196. Print.

Radford, Albert E., Harry E. Ahles, and C. Ritchie Bell. Manual of the Vascular Flora of the Carolinas. 1964, 1968. The University of North Carolina Press. 956. Print.

Schulze, Dana Madsen, Joan L. Walker, and Timothy P. Spira. 2002. Germination and Seed Bank Studies of Macbridea alba (Lamiaceae), a Federally Threatened Plant. Castanea 67:280-289.

Wade, D. D. 1978. Seymeria infestation and prescribed burns. Southern Journal of Applied Forestry 2:2

0148-4419.