1922.] 



shire, Lancashire, Gloucestershire and Lincolnshire where from 

 25 to 55 per cent, of the ears were attacked. The following 

 case is also recorded : — in a northern county a chance sheaf of 

 wheat was taken from the binder and the ears counted : 525 were 

 found affected with bunt and 563 free, i.e., 48 per cent, of the 

 wheat was infected! In Kent— East Kent, Mid-Kent and the 

 Weald — bunt is far too prevalent, and serious infestations have 

 occurred in crops of the varieties Standard Eed, Yeoman and 

 Marshal Foch. In one case a farmer growing Marshal Foch for 

 a firm of seedsmen, had the crop thrown on his hands on account 

 of the prevalence of bunt. 



Whilst the worst infected fields are doubtless due to the farmer 

 saving seed from a bunt-infested crop, the disease is present 

 also in seed-wheat sold by seedsmen. In 1921, in a field of 

 wheat (Standard Eed) grown on Wye College Farm from seed 

 supplied by a firm of seedsmen in the south of England, a 

 counting of a sample of 1,000 ears in the field showed 5.1 per 

 cent, of bunted ears — a serious infestation. 



Pickling of Seed. — In 1921, in this Journal* the writers 

 pointed out : (1) that the common method of (i pickling " wheat 

 with a solution of " bluestone " (copper sulphate) was too dan- 

 gerous, experiments showing that a solution of bluestone suffi- 

 ciently strong to kill the spores of bunt present on the seed- 

 wheat causes serious injury to the germination of the wheat; 

 and (2) that a certain method of using a solution of formalin 

 kills the bunt syores without appreciably affecting the germina- 

 tion of the seed -wheat. 



Further field experiments have been carried out in 1921 and 

 1922, and their results, described below, show very clearly that 

 by the use of a very dilute solution of formalin a simple, safe 

 and cheap method exists for the prevention of bunt. 



In our previous article cited above we wrote : " It is to be 

 feared that many cases of a ' poor plant ' in wheat may have 

 been caused by the seed having been ' pickled ' with too strong 

 a solution of copper sulphate." Evidence we have collected 

 since confirms this opinion. From inquiries we have made of 

 farmers we have ascertained that it is often the case that a field 

 sown with seed-wheat treated with a 10 per cent, solution of 

 bluestone will show a poor and tardy germination, while where 

 it has happened that a portion of the same field has been drilled 

 with untreated seed-wheat of the same kind the germination has 

 been good and quick. In one case a farmer (in East Kent) sent 



* Vol. XXVII, 19'-!1, p. 1013. 



d 2 



