EIGHTEENTH ANNUAL YEAR BOOK— PART VIII 449 



In 1917 there was again some smut in -each of the plots where the 

 seed was treated with the one to forty solution, hut in no case did the 

 smut reach 1 per cent of infection. The plots treated with the 1 to 

 5, 1 to 20 and 1 to 30 solutions in a few instances showed an occasional 

 smutted head. The total per cent of smut in different plots amounted 

 to .2, .4, .13, .25, and .87 per cent. Not a single smutted plant was 

 found in the plots treated with the 1 to 10 solution. The untreated 

 seed produced plants with 11.5 per cent smutted heads. 



The solution made with one pint formaldehyde and ten gallons of water 

 is recommended for use, not primarily because the largest yields was 

 secured from this treatment in 1916 and the next to the largest yield 

 in 1917, but because the required amount of formaldehyde can be applied 

 in this solution to kill the smut without wetting the oats enough to make 

 drying necessary. 



Repeated trials have shown that twelve hours after the oats are treated 

 with the 1 to 10 solution, they v.ill run thru the drill as raoidly as 

 will the untreated seed, and this is secured when the oats are sacked 

 immediately following treatment. 



No relation was found to exist between the number of hours that 

 the seed was covered and the killing of the smut or the yield in the 

 field. 



ANTI-SMUT COMPOUPOJS 



In the spring of 1917 certain anti-smut compounds, under various 

 names, were placed on the market as substitutes for formaldehyde. 

 Farmers are cautioned against the use of these, for there is no other 

 material known which is better than formaldehyde (or formalin) for 

 killing the smut, and the experiment station knows of none as good. 

 Moreover, the cost of these substitutes, per bushel of seed treated, 

 is much the greater. But, regardless of cost, the money spent for most 

 of them may be considered wasted as they have no value whatever in 

 killing smut, whereas the value of formaldehyde has been fully established 

 by twenty years of satisfactory use. 



THE ATOMIZER METHOD 



Some work in treating oats for smut has been done at Cornell and 

 Michigan agricultural experiment stations to determine the value of 

 using a stronger solution of formaldehyde by applying it to the oats 

 in the form of a fine spray. In this method one pint of 40 per cent 

 formalin is mixed with one pint of water, the quart solution being 

 sprayed over fifty bushels of oats while the oats are shoveled in order 

 that the formalin may be distributed as uniformly as possible. After 

 applying the formalin, the oats are piled and covered for five hours 

 when they are ready for seeding. This method is reported to have 

 completely killed the smut. While the Iowa station has made no tests 

 with this method, it would seem that the treatment is in its essentials 

 much like the method now recommended by this station. The choice 

 between the two methods depends upon the convenience of operation. 

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