294 



Bulletin No. 205 



[March, 



Panicum dichotomiflorum Michx. 



Sprouting Crab Grass (Fig. 51) 



Panicum proUferum, Lapham '57, 548, 549; Patterson '76, 52; Tlagg '78, 

 284; Brendel '87, 64. Paniciim dichotomiflorum, Hitchcock and Chase '10, 51. 



Entire plant usually smooth and glabrous- culms 1 to 4 feet long, 

 somewhat flattened, usually spreading at the base, but sometimes erect, 

 geniculate at the nodes, the nodes often consider- 

 ably swollen ; sheaths loose, very often purplish ; 

 blades 4 to 20 inches long, 3 to 20 mm. broad; 

 spikelets smooth, 2 to 3 mm. long, usually 2.5 mm. 

 This species is usually found in moist ground 

 and along ditches and streams, and generally pro- 

 duces a very rank growth. It also occurs as a weed 

 in waste places and cultivated soil, often forming 

 a rank growth after crops have been removed. In 

 such situations it must be regarded as a weed, but 

 it is not usually very troublesome as it is an annual 

 and can be easily controlled if thoro cultivation is 

 given the soil and no seed is allowed to form. 



ILLINOIS specimens: Without locality, Tasey. champaign go. Champaigii, 

 Giths, Oct., 1886; Champaign, Mosher, Oct., 1914; Urbana, Gihhs, Sept., 1898; 

 Urbana, Seymour, Aug., 1880; Urbana, Mosher, Sept., 1914. christian CO. 

 Taylorville, Andrews, Aug., 1898. cook go. Chicago, TJmhach in 1896; Chicago, 

 Moffatt 374. fulton go. Without locality, Pepoon 485; Canton, Wolf. Han- 

 cock GO. Without locality, Meod in 1842. jackson co. Makanda, Seymour, Aug., 

 1880. JO DAVIESS CO. Warren, Pepoon 485. kankakee ro. Kankakee, De Selm, 

 Sept., 1913. PEORIA GO. Peoria, Brendel; Peoria, McDorudd 71. piatt CO. White 

 Heath, ilf057ier, Oct., 1914. st. glair co. Without locality, E^f/c?-* 110; Mascoutah, 

 Welsch. WABASH GO. Without locality, /Sc7inec7i: in 1904 ; without locality, /S/iCorer; 

 Mt. Carmel, Schneck. in 1888. 



Fig. 51. — P. dicho 

 tomiflorum, spike 

 let 



CAPILLARIA 



The plants in this group arc all annuals. They are very pubescent, 

 usually on both culms and leaves, but at least on the leaves. The 

 hairs arise from small, rounded papillae. The ligules are about 3 mm. 

 long and are fringed w^th hairs. The panicles are of the type shown 

 in Fig. 33, usually large, from 4 to 18 inches long, and at maturity they 

 often break away from the plant and become tumble-weeds. The 

 spikelets are smooth and the first glume is always at least one-third the 

 length of the spikelet. Six species of this group are found in Illinois. 



Panicum barbipulvinatum Nash 

 (Fig. 52) 



Hitchcock and Chase '10, 63. 



Culms erect, 6 inches to 3 feet long, pubescent below the nodes; 

 sheaths very pubescent; blades sparsely pubescent on both surfaces. 



