1910.] Summary of Agricultural Experiments. 937 



at four points about two feet away from each hill. The hills in the other 

 row were left untreated. 



The hills in each row were trapped with mangold in the usual way* 

 and after about three weeks the traps were pulled out and the wire- 

 worms carefully counted. 



In eighty hills in the row treated with bisulphide there were 336 

 wireworms, whilst in eighty hills in the untreated row there were 362 

 wireworms. This result shows that the injection of carbon bisulphide is 

 of very little use for wireworm in hops. 



Experiments with Hop Washes (Journal of South-Eastern Agric. 

 Coll., No. 17, 1908). — From theoretical considerations, a wash made 

 from soft soap alone would be as effectual for killing hop aphis as a 

 mixture of soft soap and quassia containing the same amount of soap, 

 the argument being that the soft soap will kill all it touches, and that 

 the addition of the quassia is therefore unnecessary. The majority of 

 practical hop growers, however, find that the mixture of soap and 

 quassia is more effectual. 



In order to test this point, the main part of the College garden was 

 washed twice with a horse machine with a wash containing 7 lb. of 

 soft soap and 7 lb. of quassia per 100 gallons, and on the same day 

 10 rows were washed with a solution of 7 lb. of soft soap only per 

 100 gallons. 



The number of live lice three days after each washing was care- 

 fully counted on 100 selected leaves, and for every louse on the leaves 

 washed with soap and quassia there were two lice on the leaves washed 

 with soap alone. Alter the second and third washings the ratio was 

 still greater, and the results showed that soap and quassia is much more 

 effectual than soap alone as a wash for hop aphis. 



A patent paraffin soap wash was also tried in comparison with soap 

 and quassia, but proved very inferior. The value of a solution of soap as 

 an aphicide is due to the fact that the solution is capable of forming 

 a lather, and when hop leaves and aphis are washed with this, it wets 

 them and forms a thin film over their surfaces, and so covers up the 

 breathing pores of the lice, which are, in consequence, suffocated. 

 The presence of the paraffin in this wash prevented the soap solution 

 from forming a lather, and consequently in this case the soap did not 

 help to kill the aphis. 



Warble Flies (Journal of Dept. of Agric. for Ireland, January, 1908, 

 and April, 1909). — These publications record the experiments carried 

 out by Professor G. H. Carpenter and J. W. Steen. 



The general conclusion arrived at was that the various dressings 

 that have been recommended as preventing egg-laying by warble flies 

 are valueless as a protection. Calves and yearlings which were sprayed 

 all over every day from June to September were found to be struck 

 by the fly and to have as many warbles the next spring as animals 

 altogether untreated. 



The smear made of train-oil, spirits of tar and sulphur proved not 

 only useless but directly harmful when applied to calves, as it made 

 the hair come out and rendered the skin sore. It did little injury to 

 yearlings or older cattle unless used very frequently. 



The common warble fly in Ireland is Hypoderma bovis, not as in 

 England, H. lineata, and observation showed that the eggs are laid 



