33^ 



THE CEREALS IN AMERICA 



the beard is on the flowering glume, or that portion of the hull 

 farthest from the center of the spike, any pressure from without 

 will break the beard off without disturbing the hull, while 

 pressure from within outward is liable to peel off a portion of 

 the hull. Obviously the extent of such injury will depend upon 

 the condition of the grain at the time of threshing. 



II. FUNGOUS DISEASES AND INSECT ENEMIES. 



Loose smut on bartey . A, two-rowed 

 variety; B, six-rowed vanety One- 

 third natural size 



462. Fungous Diseases. — Barley is sub- 

 ject to black stem rust and orange leaf rust, as 

 in wheat. (146) The leaves ar^, also attacked 

 by the conidial stage (Oz'dziafi mo7iilioides Lv.) of 

 the powdery mildew (ErysipJie ^raminis D. C), 

 whose greyish, mouldy tufts cause discoloration 

 of the tissue. The loose or naked smut 

 (Z7.c///<z^£>«wa'« (Jens.) Kell. and Sw.)-not infre- 

 quently reduces the spikelets to a sooty mass 

 of spores. The covered smut {U. hordei (Pers.) 

 Kell. and Sw.) is less common. The modified 

 hot water treatment may be used for both 

 smuts. Soak the seed grain for four hours in 

 cold water, let stand four hours in wet sacks, 

 then immerse for five minutes in water at a 

 temperature of 130*' F., which is three degrees 

 lower than for wheat. (148) It has been sho-^^Ti 

 that formalin solution will kill covered smut. 1 



463. TxsECT Enemies. — Barley is com- 

 paratively free from insect attacks. However, 

 barley probably suffers more from attacks of 

 chinch bugs than any other cereal ; whether it 

 is because the chinch bugs prefer the barley or 

 the barley is less able to resist their attacks is 

 less clear. (151) The Hessian fly also attacks 

 barley, although ordinarily it is not so destruc- 

 tive as in wheat (152) ; so also does the wheat 

 bulb worm. (153) Barley is also attacked by a 

 joint worm (^Isosoma hordei Harris), v.'hich pro- 

 duces galls at or near the nodes or joints of 

 the culm. 



I E, S. R. XII, p. 457- 



