Dichanthel ium wilcoxianum (Vasey) Freckmann 



Poaceae 

 Wilcox's panic grass 

 Description 



1. General description: Perennial grass forming a winter 

 rosette with basal leaves distinctly different from growing 

 season culm leaves. The blades are not elongate, the culms 

 are branched at the nodes, and the blades are erect throughout 

 the plant giving it a distinctly tufted appearance. Spikelets 

 are blunt, inflated, strongly nerved. Sheaths 3-4 mm (.12-. 16 

 in) long, sheaths papillose-hispid, but leaves not velvetey 

 and nodes not bearded or obscurely so. Panicle narrow, 

 branches erect or spreading only at anthesis (from Hitchcock 

 1971) . The species is reported to flower primarily from May 

 to June, with some secondary blooming continuing until fall 

 (Great Plains Flora Association 1986) . Within the study area, 

 the populations were mostly in early fruit by 12 June. On 2 

 July, some fruit dispersal had occurred, and pubescence on 

 some glumes was diminishing. Late fruit production was 

 observed on 28 August. 



2. Technical description: Vernal culms 10-25 cm tall, 

 copiously papillose-hirsute, as are sheaths and blades; ligule 

 1 mm long; blades firm, erect 5 to 8 cm long, 3 to 6 mm wide, 

 usually involute-acuminate; panicle 2 to 5 cm long; spikelets 

 2.7 to 3 mm long, papillose-pubescent;. Autumnal culms 

 branching from all the nodes, forming bushy tufts with rigid 

 erect blades (Hitchcock 1971) . 



3. Diagnostic characteristics: This species is easily 

 distinguished within the study area by its habit and leaf 

 pubescence. The plants are small, generally 1.5 dm (5.9 in) 

 or less, with pubescent stems much branched from the base, 

 forming small clumps. The leaf blade is hirsute, especially 

 obvious along the margins. The blades diverge 

 characteristically from the stems at a sharp, upward angle, 

 forming a "V" shape, and end with a point. The spikelets are 

 typically "hidden" among the leaves and stems, rarely 

 exceeding them, and are usually much shorter. They are 

 distinctly pubescent (although a few individual spikelets may 

 tend to lose the hairs with age) . This combination of 

 characters is distinctive and insures separation from any 

 other grass. The most distinguishing character of the species 

 is its inflated perigynium with a short, 0.1 to 0.6 mm (.004- 

 .024 in) beak. It somewhat resembles a very minute 

 watermelon, which tapers slightly towards the base, with a 

 short but obvious beak on top. In addition, the lower bracts 

 are sheathless or nearly so, and the lowest bract is shorter 

 or equal to the length of the inf loresence. Lower spikes are 

 mostly erect, and the terminal spike is entirely staminate 



(from Hitchcock 1971) . 



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