130 prize essay : 



Smut — Bunt Ear. 



(Uredo Segetum.) 



230. Affecting the flower of the Avheat plant, and reducing the 

 ears to black masses of sooty powder. The spores of this fungus 

 are extremely minute. M. Bauer says, that the one hundred and 

 sixty thousandth part of a square inch contained forty-nine of 

 them, therefore, it would require seven millions eight hundred 

 and forty thousand to cover a square inch of surface. How in- 

 conceivably great the luimber required to fill one cubic inch ! 

 and yet every field of wheat contains thousands of grains of 

 smutty wheat. The extreme smallness of the sporules leads to 

 the supposition that they enter the plant through the spongioles 

 of the root, and rise with the ascending sap. 



Remedial Measures. 



23 1 . In 1 842 a commission was appointed at Rouen, in France, 

 to determine the best process for the preparation of wheat for 

 the prevention of smut. Their labours extended over several 

 years, and resulted in the recommendation of the use of sulphate 

 of soda, and lime, in preference to sulphate of copper, (blue 

 Titriol,) arsenic, and other poisonous preparations. They also 

 decided that wheat steeped in a solution of sulphate of soda, 

 and dried with lime, yields the soundest and most productive 

 grain. (See paragraph 11 7, for proportions.) 



232. Metzger, in Germany, after a trial of 22 years, found 

 only one single injured ear in all his crops, by mixing the seed with 

 soap-suds and slacked lime. The wheat was prepared three days 

 before it was sown, or until it began to germinate. He says, 

 "' If sown earlier after mixing with the lime it will be liable 

 to smut."(^) The object aimed at in preparing seed wheat against 



(1) See a paper on the selection, change, preparation and sowing of wheat seed, 

 by D. J. Browne, in P.O.R., for 1855. 



