466 



Wheat, hit by hail on the 4th of June, was peculiarly injured. Besides 

 the well known hail wounds, plants were found scattered throughout the 

 field with a green appearance and almost empty heads. In July, the kernels 

 present were still green and milky. The heads, as a whole appeared a light 

 leather-brown, due to the discoloring of almost all the glumes. Among 

 these were found short, fresh green tips which belonged to the sprouted 

 small heads. These contained six to eight blossom primordia, not one of 

 which had developed, and the uppermost showed only the beginnings of the 

 anthers. The glumes were lancet-like, dark green and as soft as any 

 herbaceous growth, so that a distinct transition to a foliage character was 

 recognizable. In one case young plants had actually sprouted out of the 

 base of some small heads. 



Behrens^ observed similar conditions in hops after a hail storm occur- 

 ring on the first of July. Four weeks later the blossoming catkins opened 



Fig. 



Cross-section through the stalk of the wheat head of th( 

 at the place broken by hail (h). (Orig ) 



•vious figure, 



and contained only leaflets. The author's experiments connect this trans- 

 formation of the inflorescence actually with the destruction of the leaves 

 by hail. On vines from which the leaves had been stripped, the so-called 

 brausche hops grcAV (see p. 344), while on the stems on the same place 

 which had not been stripped, catkins developed normally. 



In potatoes, it has been observed that injuries due to hail reduce the 

 starch content of the tubers-. Injury to the pods may seriously afifect rape. 

 It is a matter of course that, in all cultivated herbaceous plants, the destruc- 

 tion of the leaf must afifect the yield — even to the loss of the harvest. // 

 would be a mistake to remove foliage injured by hail. Experiments with 

 cabbage plants showed that better heads were obtained when the injured 

 foliage had been left than when it had been removed. 



1 Zeitschr. f. Pflanzenkrankh. 1896, p. 111. 



2 Jahresber. d. Sonderausschusses f. Pflanschutz 1903, p. 94. 



