108 Phytologia (Aug 2004) 86(2) 



site. The dominant tree species at the sites included: Acer rubrum, A. 

 saccharum, Liquidambar styraciflua, Quercus alba, Q. muhlenbergii, Q. 

 shumardii and Vaccinium elliottii. Common herbaceous plants included 

 Chasmanthium sessilifolium, Solidago caesia, and Carex spp. These 

 populations are about 200 km west of the nearest known occurrence in 

 Arkansas in Grant Co. (USDA, NRCS. 2004) and approximately 100 km 

 northeast of the nearest known Texas occurrence in Lamar Co. (Singhurst 

 et al., 2004). 



Voucher specimens: OKLAHOMA. Mc Curtain Co.: Beaver Bend 

 State Park, Mt. Fork Creek trail below Beaver Bend Lake, 0.7 mi. S of 

 spillway, 6 Oct 2000, Singhurst 10118 (BAYLU); Beaver Bend State 

 Park, park dam trail, 0.4 mi. S. of dam, 6 Oct 2000, Singhurst 10115 

 (BAYLU); Beaver Bend State Park, W side of Mt. Fork River below 

 dam, 20 Oct 2002, Singhurst & Singhurst 11343 (BAYLU); Beaver Bend 

 State Park, W side of Mt. Fork River below Broken Bow Reservoir dam, 

 19 Oct 2003, Singhurst & Singhurst 12355 (BAYLU); Beaver Bend State 

 Park, W side of parking lot turn around at trail entrance of park dam, 19 

 Oct 2003, Singhurst & Singhurst 12534 (BAYLU). 



Two other species of Prenanthes occur in Oklahoma, P. altissima 

 L. andP alata (Hook.) D. Dietr. (Milstead 1964). Prenanthes altissima 

 is distinguished by its yellow to green-yellow florets numbering about 

 five or six per capitulum. Prenanthes alata, which has a similar flower 

 color and floret number to P. barbata, is characterized by its triangular 

 to occasionally elliptic basal leaves that are slightly hastate at the base. 

 Prenanthes barbata has oblanceolate to elliptic basal leaves that are 

 never hastate. 



Prenanthes barbata is considered to be rare in Texas (Correll and 

 Johnston 1970), and since it is now known from only four populations 

 at Beaver Bend State Park, it should be considered as a candidate for 

 sensitive species status by the Oklahoma Natural Heritage Inventory. 



Parentucellia viscosa (L.) Caruel (Scrophulariaceae). This Old World 

 native has been naturalized on the west coast (California, Oregon, and 

 Washington) and in the south central (Arkansas, Louisiana, Mississippi, 



