SPRAYING TO kILL WEEDS.

Dominion, Volume 2, Issue 522, 1 June 1909, Page 10

SPRAYING TO kILL WEEDS.

The search for chemicals which will kill weeds bnt not injure tho crop in which they are grow-ing achieved success-some years ago, and improvements are still going on. Tho Bangor College, in North Wales, has beon working on charlock with sulphate of copper. ' The charlock, which generally flourishes in' corn crops, is unassailable by any other means, but oven if hoeing or pulling were practicable tho expense would bo much greater than that incurred by. spraying with a solution of copper sulphate. Last year experiments were conducted at fifteen centres, and at each centre three dressings of different strengths were usod, namely, a 3 per cent, solution, a 4 per cent." solution, and a '5 per cent, solution, or. 151b., 20lb:> and 251b. copper sulphate respectively to ■fifty gallons of water. At the. whole of the stations tho effects were conclusive, both as to tho efficacy of the treatment and tho superiority of the strougest dressing. In the drier districts Lof England' & 3 per coat, &olution at' the

rate of fifty gallons per aero is generally sufficient, -but in North Wales cither a 4 or 6 per,cent, solution, and preferably the latter, should be applied. Charlock is not tho only weed which is susccptiblo to the fatal influences of tho copper sulphate spray. A 5 por cent, solution also killed spUTrey, a weed common in the district, and, like charlock, a wasteful encumberer. of tho ground: No.mention is mado this year of tho influences of tho dressing upon tho yield of corn obtained, but _ that tho yield and quality of grain aro improved by the destruction of the weeds was demonstrated some years ago, and iB generally observable where tho spraying operation is systematically adopted. At one of tile farms last yoar a crop of peas was sprayed when the' charlock was 'just comin" into flower, and while tho weed was completely destroyed by tho 4 and 5 per cent, solutions, tho peaß suffered no injury whatever, and woronot oven tinged. This result encourages tho belief that thero may be extensive possibilities in tho use of copper sulphato solutions in combating tho plaguo' of weeds in cultivated crops. ... ■ ■ ■