The Canadian Horticultdrist. 179 



83>S« SrR, — I have trimmed all ray plantation to about six stems each, and shall 

 allow no new wood to grow till I have had three good crops ; then I shall cut one stem 

 away and permit a new one to grow in its place. Is this about right, and shall 1 not have 

 a larger crop of larger fruit, by allowing the bush to use all its sap for the growth of fruit, 

 instc^ of part of it going to the growth of new wood ? 



Reply by Stanley Spillett, Nantyr. 



In theory this seems about right, but in practice I find that just as large 

 berries, and as many of them, will be produced, it a couple of good strong 

 shoots are allowed to grow at the same time. 



The error seems to be in assuming that a tree has so much energy, and we 

 can do no more than direct this to either growing wood or fruit. 



Meehan, I think it is, contends that every plant regulates its root growth 

 to its foliage. The more leaves, the more roots. He maintains that the suckers 

 from the roots of apple or plum trees, though unsightly, and therefore ought to 

 be cut away, do not rob the tree of nourishment, as the root growth is propor- 

 tionally increased. 



Coal Ashes. 



836. SiB, — Would you kindly inform me if you consider coal ashes good for young 

 trees. Some whom I have been casually talking to state that it is, others claim that it 

 has a tendency to harden the land after the first year. If you would give me your opinion 

 in the matter it would oblige me very much. 



W. CowiE, Port CoCborm. 



Coal ashes have little or no value as a fertilizer. They form a good mulch 

 on the surface about a tree to retain moisture, and mixed with the soil it has a 

 useful mechanical effect, in rendering it more porous. 



Powdery Mildew in Greenhouse. 



837. Sir, — I have a small 8x10 greenhouse, 6 ft. high from front wall, for starting 

 flowers and early tomatoes. I have Black Hamburg grape vine in it, just coming into 

 bearing, but the leaves are turning brown through either some disease or some insect. 

 Could you suggest a remedy ? Wm. Dick-son, ParkhiU, Ont. 



Reply by Mr. J. Craig, of the Central Experimental Farm, Ottawa. 



I cannot gather from the above description what the disease or insect is or 

 might be which would cause the injury described. An effect of this kind is pro- 

 duced by a severe attack of the powdery mildew, one of the Uncinula tribe- 

 For this I would spray the vines with Bordeaux mixture early in the season, 

 and follow with sulphur applied in the ordinary way. Such an effect in a 

 general way is also produced when the leaves are badly attacked by the grape 

 vine leaf thrip. The remedy for this insect is kerosene emulsion. 



