178 EXPERIMENTAL FARMS 



3-4 EDWARD VII., A. 1904 



the same acreage, it was 128 or 130 tons, and that at least two-thirds of the hop acreage 

 this year was afflicted with the pest. Although the loss was severe in some places, it 

 was not general throughout the district; for instance, Mr. Branscombe, of Chisholm, 

 only got two bales from three acres, his crop being almost a total failure. He stated 

 that the insects appeared first of all as plant-lice when the hops were coming into burr. 

 After that it seemed as if a blight had struck them; the vines which were affected pro- 

 duced no hops, and the leaves turned black. On a knoll in his yard the vines were 

 heavy and produced the two bales referred to. Then, on the other hand, Mr. Philip 

 Vanmeer, of Bethel, Ont., had 22 acres of hops. The centre of his yard was on high 

 ground, but the land sloped oif in all directions to low ground. His yard v/as not 

 affected, and he did nothing in the way of spraying or otherwise, in the way of special 

 treatment, except that the yard was kept thoroughly cultivated. He had a very heavy 

 crop. It would appear, then, that the abundance of this insect is not affected by the 

 land being high or low. A great many ladybird beetles were present among the 

 aphides. There was a similar visitation by the Hop Aphis in 188G, when the hop crop 

 was almost ruined; but since that time the insect has occurred only in very limited 

 numbers and has not been noticed. None, or very few, of the growers here have done 

 any spraying, as they have not the special apparatus which is necessary. I am told 

 that the spraying pumps which answer for fruit trees will not for hops.' 



Mr. Henry Corby, of Belleville, Ont., as far as I can learn, was the only grower who 

 sprayed his yards in a thorough way to protect them from injury by the Hop Aphis last 

 year. His experience, however, has been so widely commented upon by hop growers in 

 the vicinity and in Prince Edward county that I have no doubt the wise measures 

 adopted by Mr. Corby will have the good effect of inducing others to spray their yards 

 next year, should there be any appearance of the Hop Aphis. Mr. Corby writes : 



' Belleville, Nov. 19. — Your favour in re Hop Plant-louse received. In reply we 

 first noticed the Hop Plant-louse on the vines about the 1st July. From the 1st to the 

 10th they came on very thickly indeed. As I had eighty acres under cultivation, we con- 

 tinued the spraying for close on to a month. The mixture I tised, was 7 pounds of whale- 

 oil soap and 8 pounds of quassia cliips, boiled for an hour. This made 100 gallons of 

 wash. I used an English sprayer which takes two horses to draw it, but it does thorough 

 work, I consider that I lost one-quarter of my crop at least; but, had I not used the 

 sprayer, I doubt if I should have had any hops at all. The quality of my hops is first- 

 class.' 



The life history of the Hop Aphis is a remarkable one and is given in a condensed 

 form in my annual report for 1889, which I repeat herewith, as the life history has an 

 important application in this species, to the remedies which are suggested. The life 

 history of the' Hop Aphis has been carefully worked out by Prof. Biiey and recorded 

 in his report for 1888 as follows : ' Of this species the winter eggs are laid by the per- 

 fect females upon plum trees in autumn. From these hatch, the following spring, wing- 

 less females which are called " stem-mothers." These produce young plant-lice by a 

 process analagous to budding in plants and known as parthenogenesis (from the Greek 

 f.arihenos, a virgin, and genesis, production), which means the production of young 

 from imperfect and unimpregnated females, without the intervention of a male. There 

 are three broods of these parthcnogenetic females produced on various kinds of plum 

 trees, the third becoming winged. This last is known as a migrant and it instinctively 

 flies to the hop plant, which up to this time has been free from attack. A number of 

 generations of wingless females are produced upon the hop until, in autumn, winged 

 females known as the return migrants again apear. These return to the plum and 

 produce some three or more young which have no wings but are true sexual females- 

 Somewhat later than this, upon the hop vines true winged males, the only malea 

 of the whole series, are developed. These fly to the plum trees and towards the end of 

 the season may be found pairing with the wingless females, which afterwards stock tho 

 tree with eggs which pass the winter there.' 



