172 EXPERIMENTAL FARMS. 
63 VICTORIA, A. 1900 
but especially thick on the pods. The plants then turned brown and dried up so as to 
be useless as fodder. Is there any remedy for this pest? Would it be any benefit to 
have the next crop at some distance from the one infested ?—C. R. Perurs. 
‘Thornloe (Nipissing District), Ont., Sept. 14.—My crop of peas was entirely 
ruined by plant-lice about half the size of a grain of wheat, which were on the plants by 
millions. These peas were the first ever sown on my farm, as I only came here last 
fall. I would like to know if this pest is often found in open country. The clearing in 
this part amounts to only a few acres here and there, in an immense forest of rather light 
young timber. If it had not been for these lice, my peas would have been a good crop, 
as the land suits peas, so far as they have been tried by my neigbours.’—SamueEt Rerp. 
‘Toronto (York Co.), Ont.—I am greatly troubled this summer with green-flies, 
upon my sweet peas. They are in great numbers; I never saw so many as there are 
this year When I went along the vines with the spray from the hose, they would fall 
on the ground so thickly as to make it green. There was another kind which attacked 
the plants under the ground clinging to the roots. This is of a brick red colour but 
otherwise resembles very closely the green-flies which were so numerous on the leaves 
and stems. WhenI pulled up some sickly vines last summer, I also found some of these 
insects clinging to the roots. These latter are not so numerous as the green ones men- 
tioned above. Wireworms, cutworms and red spiders have also given me a great deal 
of trouble on my sweet peas this year. —Ep. LEADLEY. 
‘Freeman (Halton Co.), Ont., Aug. 7.—I send a sample of peas heavily infested 
with plant-lice. These are from a 14-acre field belonging to my cousin, F. W. Fisher, 
at Burlington, close to here. This is a fair sample; I have never seen anything like it 
before and should like to know if it is common. I should like to know what variety of 
aphis this is, for it looks as if the whole crop would be lost.’—Gro. E. Fisumr. 
This pea aphis was also very destructive to both field peas and Sweet Peas at 
Ottawa, but in the case of the field peas the outbreak occurred so late in the season 
that most varieties ripened before much harm was done. Sweet Peas in many 
gardens were badly attacked. Perhaps the worst case of infestation was upon a hedge 
of Sweet Peas planted rather late upon the Central Experimental Farm, where an excel- 
lent opportunity was afforded of watching the development of the plant-lice and also of 
a war which was waged strenuously against them by various kinds of parasites. The 
plant-lice clustered thickly around the young shoots and towards the ends of the branches, 
stunting the growth of the plants very much and preventing them from flowering. They 
appeared at Ottawa in the middle of August, and some specimens could be found right 
up to the hard frosts of late autumn. By the beginning of September several kinds of 
predaceous insects, such as lace-winged flies, lady-bird beetles and Syrphus flies, began 
to appear in large numbers, and from that time on the numbers of the plant-lice decreased 
rapidly. When the lady-bird beetles began to pupate, they crawled up above the vines 
and attached themselves to the wire netting intended for the sweet peas to climb over. 
This they studded so thickly as to be noticeable from a considerable distance. The 
species which were most numerous were Hippodamia convergens, Guér., and Coccinella 
9-notata, Hbst. Next to these were the larve of Syrphus ribesii, L. This latter, how- 
ever, was unfortunately rather commonly attacked by the hymenopterous parasite Bassus 
letatorius, Fab., which again in its turn occasionally fell prey to the small Chalcid 
Isocratus vulgaris, Walk. In addition to the above parasites many specimens of Praon 
cerasaphis, Fitch, were bred from material collected at Ottawa. In one garden another 
minute Braconid, a new species of Aphidiws, which has been named by Mr. Ashmead, of 
Washington, Aphidius fletcheri, did good service. The empty shells—the bodies of the 
hosts—from which the parasites had emerged, were very abundant on the plants. These 
hymenopterous parasites were kindly identified by Dr. Howard, U.S. Entomologist. 
T had not an opportunity to examine material from all the localities at which this 
plant-louse occurred in Canada during the past summer, but parasites in numbers were 
found at most places ; and, if the Ottawa outbreak may be taken as a guide, added to 
the fact that although so injurious this year the Destructive Pea Aphis has never 
appeared in destructive numbers before, we have reason to hope that even next year it 
may not again be the cause of serious loss. It must be noted, however, that the occur- 
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