REPORT OF THE ENTOMOLOGIST AND BOTANIST. 243 



water, with a little coal oil on the top. When the area attacked is too large for this, 

 spraying promptly with Paris green, one pound to 100 gallons of water, or dusting with 

 one pound of Paris green to 50 of flour, would destroy them. 



Referring to Mr. A. H. Chambers's experience above mentioned, I think there must 

 have been some other cause than the Paris green which destroyed his crop, for a very 

 much stronger mixture than he mentions has been used by some of my correspondents and 

 by myself without injury on the same crop. 



Locusts on Sable Island. 



In my reports for 1894 and 1895 I have referred to serious injury by locusts on 

 Sable Island, off the coast of Nova Scotia. This was so severe last year that it was 

 necessary to purchase 50 tons of hay to keep the horses and stock through the winter. 

 During the past summer the loss has been far less. The Superintendent of the island 

 writes : " September 7. — In a few days we shall have finished harvesting the hay crop, 

 which this season is large, owing to the unusual continuous fogs and heavy rains from 

 June till the middle of August. The locusts have done but little damage, although 

 plentiful. Vegetation nearly everywhere kept ahead of them." In an earlier letter 

 dated the 12thof June, the Superintendent expressed the opinion that hopper dozers could 

 not be used satisfactorily on Sable Island, owing to the uneven surface and loose sand in 

 places. He invested in turkeys and raised a large number of chickens, which doubtless 

 were useful in destroying many locusts. The young locusts first appeared at No. 4 

 Station about the 24th of May, but none appeared at Main Station until the 12th of June. 



HOOT OKOPS ^NE) VEGETA-BLES. 



Few complaints of injuries by insects to root crops during the past season have been 

 received. There were, of course, the usual applications for remedies against the Turnip 

 Flea-beetle {Phyllotreta vittata, Fab.) from all parts of the Dominion, but the loss was 

 not extensive. The best remedy — dusting the young plants as soon as they appear with 

 land plaster and Paris green (50 to 1) — is now well known. During June this insect, 

 both in the mature and larval forms, was troublesome in gardens at Ottawa upon cress, 

 particularly the curled varieties. When the plants were young, a mixture of Paris green 

 and flour was used successfully; but later, when the crop was ready for the table, dusting 

 with powdered tobacco waste was substituted, and the cress was kept closely picked. 

 The larvse, which are slender, dark brown grubs, dotted with black, are from one-eighth 

 to three-sixteenths of an inch long, and for the most part mine inside the tissues of the 

 leaves, but frequently, when nearly full grown, burrow out through the thin epidermis 

 and feed for a time on the surface. I have been unable to find these feeding, either on 

 or in the lOots. When full-fed they enter the ground, sometimes to a depth of three 

 inches, and emerge nearly three weeks later as the well known perfect flea beetles, 

 which are about one-eighth of an inch long, with two wide waved yellow stripes down 

 the back. As a rule, the larvse are not often noticed, because by the middle of June the 

 demand for garden cress as a salad or table relish has ceased, owing to the abundance of 

 radishes and similar vegetables. Injury to the leaves at this time is, therefore, of small 

 importance, as the larvse are never abundant enough to affect the formation of seeds on 

 such plants as are left for that purpose. When green leaves are required, the best method 

 is to encourage a quick growth by watering frequently and cutting as soon as the leaves 

 are fit for use. A weak solution of nitrate of soda (one ounce in three gallons of water) 

 applied carefully to the roots twice a week was found to be a quick-acting stimulant. 

 In this way succulent leaves are produced abundantly before the larvae have time to 

 develop. When, however, a bed is badly infested, the only plan is to cut the whole bed 

 and water freely ; the new growth will also start more quickly if the beds are shaded. 

 8c— 16i 



