J. \1 Collin U:\ 



weak side shoots only will be attacked. The best time lor this so\\in<i; 

 probably varies according to the season, but ( •ro})s sown in March (the 

 earlier the better) usually enjoy iumHinity from attack. It must be re- 

 membered, however, that early sowing on a bad tilth or too early sowing, 

 with damage from frost, may result in a more backward plant than some- 

 what later sowing. Sulphate of ammonia and sodium nitrate appear to 

 be two of the best top dressings for young oats, and in regard to these it 

 has been specially noted in the Oxford district (Bland, July, 1917) that 

 sodium nitrate, applied as soon as the oats are through, gave better 

 results in a drv season than sulphate of ammonia applied when oats 

 were drilled. 



Vassiliev (1914) has recorded some of the results of experiments made 

 in 1911 in the Government of Petrograd on the effect of manure on the 

 yield oifrif infested oats in a table as follows: 



Percentage 

 of plants 

 Percentage not produc- Percentage Yield per 



of plants ing normal of plants dessiatine 



Manures attacked grain killed (=2-7 acres) 



No. 1 No. 2 No. 1 No. 2 No. 1 No. 2 No. 1 No. 2 



Unmanured 4.5 41 48 49 22 20 115 68 



Superphosphate 33 3o 32 2!) 11 10 125 77 



Superphosphate and Pot- 

 ash ... 40 52 2t) 4(i 10 24 142 66 



Sodium nitrate and super- 

 phosphate 32 39 17 15 5 6 158 96 



Sodium nitrate, super- 

 phosphate and potash 40 43 11 24 4 10 156 112 



The important facts may be shortly summarised as follows : 



Percentage of infected plants on all plots ... ... ... ... ... ... 40 



Percentage of plants completely killed on unmanured plots ... ... ... 21 



Percentage of plants killed on plots manured with superphosphate at rate of 



about 267 lbs. per acre and sodium nitrate SO lbs. per acre ... ... ... 5| 



Percentage of plants on unmanured plots not producing normal grain ... ... 48i 



On plots manured with superphosphate and sodium nitrate as above the per- 

 centage of plants not producing normal grain reduced to ... ... ... 16 



The addition of potash at rate of 80 lbs. per acre to above manures, in one case 



reduced the percentage of plants not producing normal grain to ... ... 11 



Increase iii yield 37 % in one case, 65 % in another. 



He found that oats damaged by frit when manured with sodium 

 nitrate tillered well, producing new shoots which ripened at the normal 

 time, and came to the conclusion that damage caused by anything up 

 to 40 per cent, oifrif infestation could be reduced to practically nil if 

 proper manures were used under suitable conditions. 



