June, 1914.] 
The Panicums of Ohio. 
347 
THE PANICUMS OF OHIO. 
Blanche McAvoy. 
This study of the Panicums of the state and the distribution 
as given for each species are based on specimens in the state 
herbarium at the Ohio State University. All of the Panicums 
in the herbarium were studied and their identification revised 
by Hitchcock and Chase of the United States Department of 
Agriculture, while they were preparing their material for “The 
North American Species of Panicum.” It was thought advisable 
not to include any records of plants not so identified as it is some¬ 
times difficult to discover the exact species from the older names 
used a few years ago. 
Panicum L. 
Perennial or annual grasses; inflorescence usually a panicle, 
rarely a raceme; spikelet two-flowered, but the upper flower either 
staminate, sterile or reduced; the empty glumes unequal, the outer¬ 
most one often minute; lemma and palet of the perfect flower 
indurated; margin of the lemma inrolled; grain freely inclosed 
within the {Lowering glumes. 
Key. 
1. Basal leaves like those of the stem. 2. 
1. Basal leaves unlike those of the stem. 10. 
2. Basal leaf-sheaths compressed, often keeled. 3. (Agrostia). 
2. Basal leaf-sheaths round, little flattened, never keeled. 4. 
3. Fruit stipitate. Panicum stipitatum. (2). 
3. Fruit not stipitate. Panicum agrostoides. (1). 
4. Leaf-sheaths smooth, panicle smooth; tall perennials having long root¬ 
stocks or stolons with numerous, small, broad, scale-leaves. 
Panicum virgatum. (3). 
4. Leaf-sheaths pubescent, or if smooth, then the branches of the 
panicle pubescent; annuals. 5. 
5. Leaf-sheaths smooth, panicle branches rough pubescent. 
Panicum dichotomiflorum. (4). 
5. Leaf-sheaths pubescent. G. 
G. Spikelets ovate, more than inch long, spikelets close. 
Panicum miliacium. 
G. Spikelets lanceolate or elliptic, less than ps inch long; spikelets 
distant. 7. 
7. Panicle narrow', branches of the panicle ascending; spikelet less than 
Hs inch long. Panicum flexile. ( 8 ). 
7. Panicle spreading when mature; spikelet xs inch or less long. 8 . 
8 . Panicle very large, usually p£ the plant. Panicum capullare. ( 6 .) 
8 . Panicle not so large, usually 1 of the plant. 9. 
9. Stem delicate; leaf blade less than pf inch wide. 
Panicum philadelphicum. 9. 
9. Stem stout; leaf-blade usually p£ to ps inch wide. 
Panicum gattingeri. (7). 
10. Leaf-blades pz wav up the stem less than p£ inch wide, attenuate to 
cordate at the base. 11. 
10. Leaf-blades way up the stem inch or more wide, usually cor¬ 
date to clasping at the base. 30. 
