33. 



lets, three occurring at each joint, only one is perfect (bearing 

 stamens and pistil). The two other spikelets are awl-shaped 

 and rudimentary; these are borne on short stalks. One of these 

 sterile spikelets occurs on each side of the perfect flower which 

 bears a long awn. At each joint will be found six empty long- 

 awned glumes spreading at maturity. These give to the plant 

 the bristly appearance at maturity. When mature the spike 

 breaks up into joints consisting of the rudimentary spikelets and 

 a perfect flower, so that each joint has one "seed." The num- 

 ber of "seeds" in a spike varies from thirty-five to sixty. A 

 single cluster of plants may therefore produce from three hun- 

 dred to two thousand mature "seeds." The plant has a won- 

 derful capacity for "stooling. " From a single plant as many 

 as forty spikes may be produced, and the number no doubt often 

 exceeds this. 



CRAB GRASS (Panicum sanguinale L.} 



A much branched, leafy annual one to three feet high, spread- 

 ing on the ground, with erect, smooth, spreading culms, frequent- 

 ly rooting at the lower joints. Joints smooth, though more fre- 

 quently bearded with de'flexed hairs. Sheaths loose, generally 

 pilose ; hairy, ciliate on the margins, with a membranaceous ligule. 

 Leaves two to four inches long with rough margins, occasionally 

 pilose at the base. Flowers produced in digitate spikes hence the 

 common name finger grass is sometimes given it. Spikelets less 

 than one-eighth of an inch long in pairs, one nearly sessile the 

 other with a stalk. Each flower consisting of two sterile glumes 

 (chaff) and the flower proper. The first bract very small, the 

 second about one-half to two-thirds as long as the spikelets, us- 

 ually hairy on the margin. The third glume somewhat longer 

 than the fourth which is five nerved and usually silky-villous 

 along the marginal nerves. Fourth glume smooth and acute. 

 The fruit is minute, pitted and cross striated, light straw color 

 except Avhere the sterile glumes remain attached. These are gray 

 in color and minutely hairy. 



SEDGE FAMILY (Cyperaceae.) 



Of the Sedge Family the most important weed in the state is 

 the northern nut grass (Cyperus esculentus) ; this plant is read- 

 ily recognized by the yellowish cast of the corn field in the 

 spring and the little plant has corms or bulbs, and with roots 

 which enables it to spread. 



DOCK AND SMARTWEED FAMILY (Polygonaceae.) 



This family also contains a large number of important weeds 

 many of them are very troublesome to our crops. Mention may 

 be made of smartweed, tanweed or devil's shoestring, sheep sor- 

 rel or horse sorrel, all common weeds in this state. 



