2 F^Ht Fly (Osciiius Frit) attacking Winter Wheat 



The wheat was sown on Oct, 14th— 20th and received 10 loads of 

 farmyard manure per acre. 



On all these fields about 25 % of the plants were attacked when 

 examined on February 9th. No attack of "frit fly" was noticed in 

 the spring corn of 1915. 



Neighbouring fields of wheat were visited and "frit fly" larvae 

 were found in all cases. 



A field of rye joining a field of badly attacked wheat was apparently 

 free from "frit fly." 



In December, 1912, and January, 1913, Edmunds^ found "frit fly" 

 larvae in Eye Grass in a clover ley and also in Golden Oat Grass {Avena 

 flavescens) and in False Oat Grass {Arrhenatherum avenaceum). 



Baranov has also recorded the spring generation of flies as laying eggs 

 on the following grasses: Phleum pratense, Alopecurus 'pratensis, Lolium 

 perenne, Triticum cristatum, Festuca pratensis, Avena flavescens and 

 Poa pratensis. 



The writer also found "frit fly" larvae on Italian Rye Grass {Lolium 

 italicum) on March 6th, 1916. 



In this connection it is interesting to note that the above attacks 

 are all after crops of Rye Grass or Italian Rye Grass. 



The 18 acre field was ploughed up on May 1st — 3rd and sown with 

 Barley on May 4th which on threshing showed a yield of 36 bushels 

 per acre. The other two fields were left and yielded about 20 bushels 

 of wheat per acre. It will be seen from this that the '" frit fly" is capable 

 of causing a considerable reduction in the yield of winter wheat. 



On February 21st, 1913, a sample of Winter Oats and Vetches was 

 received from Wickham Market, Suffolk, and in the Oats larvae of the 

 "frit fly" were found. This crop followed a crop of late-sown spring 

 oats and was sown on October 12th. 



The above observations are interesting in connection with the life 

 history of the "frit fly." 



Mr Littlewood's wheat was sown about December 1st and Mr 

 Sheringham's wheat which was not sown until November 14th was slow 

 in coming up. If the " frit fly " has only three broods in a year we should 

 have expected the wheat to be safe from an attack under these con- 

 ditions. Is this attack of winter wheat caused by the third brood of 

 flies which hatch out from the pupae in the ears of oats or from 

 those in the shoots of cereals or grasses (usually in September), or is it 

 a fourth brood? In this connection the following may be of interest: 



* Joint Report, Harper Adams College, 1912. 



