APPLE DISEASES

Timaru Herald, Volume CXLVI, Issue 21244, 14 January 1939, Page 13

APPLE DISEASES

DUE TO THE EACK OF BORON SUPPLYING THE DEFICIENCY Recent experiments have demonstrated that internal cork of apples, and the crackling and die-back disease affecting pears, result from a deficiency of boron in the soil. Boron, in the form of borax or boracic acid, applied in small quantities to the soil, is taken up by the trees and completely checks these troubles. An application of from one-half to on,e pound of borax a tree is said to be sufficient for at least two years, though it is not yet known how long a single dressing will remain effective. When boron is applied through the medium of a sprayed solution, much smaller quantities have proved sufficient. The concentration recommended is a 1 per cent, solution and the sprays may be combined with lime sulphur or lead arsenate, and may be applied as late as early November in the case of trees which have not received a boron dressing during the previous two years. It is not known for how many seasons these dilute sprays remain effective, but tests are in progress to secure information on the point.