QUESTION DRAWER. 



of the White Grubs, a name given to the 

 preparatory stages of the different spe- 

 cies of the June Beetles These are 

 frequently very destructive in strawberry 

 beds, in the second year of their growth. 

 For this reason many fruit growers have 

 adopted that method of growing straw- 

 berries in which the young plants are 

 set out one spring and the crop, is taken 

 from them the next season and the plants 

 are then ploughed up, and a fresh bed 

 is started. The first year the plants are 

 so small that the beetles are not attracted 

 to them to lay their eggs, and by plow- 

 ing up the second year, if eggs have been 

 laid that season the young grubs are de- 

 stroyed before they have grown large 

 enough to be very destructive. Mr. 

 Craig tells me that this method is now 

 generally practised by growers who cul- 

 tivate strawberries in a large way for 

 commercial purposes, so that in this 

 happy instance we have both a satisfac- 

 tory horticultural method, and one which 

 serves as a good remedy for controlling 

 one of the worst insect pests of this im- 

 portant crop. 



Small Flies in Window Gardens. 



938. Sir, — How can I get rid of those 

 very small Hies that come out of the rich earth 

 in the potted plants ? Does it show it is too 

 rich ■; 



R. H. Light, Kingston. 



Reply by Dr. /as. Fletcher, Entomologist, 

 Experimental Farm, Ottawa. 



It is impossible to give the exact name 

 of the fly referred to above without spe- 

 cimens, because there are several spe- 

 cies, the lanw or maggots of which occur 

 in the earth of house plants. It is pro- 

 bably a species belonging to the genus 

 sciara, and is possibly sciara iiiconstans 

 of Fitch, but it is just as likely to be 

 some other species. 



I do not know of any better method 



of preventing the presence of these mag- 

 gots than the liberal use of very finely 

 ground tobacco du^. This, of course, 

 is a very safe thing to use, and other 

 remedies would probably be less safe 

 with the comparatively tender house- 

 plants. The use of such substances as 

 kerosene emulsion, or hot water even, 

 and especially of bisulphide of carbon, 

 are all attended with some danger, ex- 

 cept when used with caution and some 

 preliminary experience. The efficacy of 

 the tobacco dust is much greater if 

 finely ground. 



The question as to whether the soil 

 is too rich must be decided by the be- 

 haviour of the plants. If too rich soil 

 is used, the plants are apt to run too 

 much to leaf instead of blossom. The 

 maggots of these flies feed on the decay- 

 ing vegetable matter in soils, so that 

 their presence would merely indicate 

 that the soil contains this material. The 

 tobacco dust not only destroys insects 

 but has valuable fertilizing qualities. 



Borer in Acacia. 



939. .Sir, — Can you give me a preventive, 

 or a destroyer of the borer that has begun 

 working in the blackthorn acacia ? We have 

 beautiful specimens of the honey acacia, forty 

 feet in height and thirty-five years old, and 

 our grounds would be spoiled if these were de- 

 stroyed. 



Mrs. \V. L. Tvson, < larUhunj. 



Reply by /as. Fletcher, Experimental 

 Farm, Otta^va. 



I regret to say that there is no prac- 

 tical remedy for the Locust Borer. When 

 the trees are not too large, they can, of 

 course, be washed with one of the alka- 

 line washes, which are so efficacious 

 against the well-known borers in fruit 

 trees ; but when the locust or acacia 

 trees have grown to a large size, it is 

 impoisible to do anything to preserve 

 them against the attacks of the borer. 



