PREVENTIVE AND C< i.MI'.ATIVK MEASURES. < ; 7 



to handle in such a basket would be a full half-bushel. The 

 hot water is best contained in two large boilers, the first at a 

 moderate temperature, serving to wet the grain somewhat ami 

 to prevent cooling of the water of the second boiler, which 

 must be maintained between 130 F. to l.">4 F. A lower 

 temperature will not ensure death of all spores, a higher will 

 injure the grain. The grain is immer^-d a few minutes in the 

 first boiler, then placed in the second for fifteen minutes, being 

 meanwhile frequently shaken to ensure complete sterilization. 

 Next the basket and its contents are cooled in cold water and 

 the -rain spread out to dry. 1 



The important point in the application of these methods is 

 their general and simultaneous use throughout a whole district. 



For smut-diseases the removal of diseased plants is at the 

 same time a preventive and a combative measure. This is 

 not difficult where the plant is large or the disease conspicuous, 

 as with the maize-smut ; the diseased plants can then be re- 

 moved and burnt before the smut-spores are shed. If the smut 

 is not very prevalent it is possible to keep it in cheek by 

 removal of diseased specimens on such crops as maize, barley, 

 wheat, and oats. This treatment can also be applied to some 

 warden-smuts like that <>n violets. 



llrefeld recommends as a preventive measure the avoidance 

 .if the use of fresh farmyard manure. Smut-spores from in- 

 fected hay ..r straw, which tinds its way to the manure heap, 

 -'rminate there and multiply yeast-like giving rise to couidia, 

 which, on exhaustion of nutrition, give rise to germ-tubes 

 capable of infecting seedling plants. The spores are capable of 

 -ermination even after being eaten with the fodder and passing 

 through the digestive canal of animals. In this connection 

 Professor \Vollny carried out the following experiment at my 

 instigation : three field- -ituated at some distance from each 

 other were sown with inai/e, which I had mixed with living 

 spores of r.^fi/iii/n HKii/ilix collected the previous autumn. < 'in- 

 field was left unmanured, the second received old farmyard 

 manure, the third fre-li. All plants in the first plot -ivu up 



healthy, two of the second were diseased, and eleven of the 



third. The summer hem- a dr\ one the number of di-.-a-ed 



- 



1 I,, !),.- literature Inued fn.m il,.- I'nit.-.l State* K\i>-i 

 ,tlit-r "steep en, iili H-sults. i VA\\ . i 



