THE ORCHARD.

Hawke's Bay Tribune, Volume XI, Issue 243, 18 October 1921, Page 7

THE ORCHARD.

CONTROL OF INSECT PESTS, ETC. (By J. W. Whelan, Orchard Instructor) As stone fruits have now set, and th© majority of pip fruits are either in ’blossom or at the open cluster stage, care must be exercised ay to spraying. Bordeaux, although strongly recommended as a control tor iungus diseases, must now bo discontinued, as it is liable to burn fruit and foliage, even at- a weak strength-. roni now on lime-sulphur, 32deg. Baume test, will take the place of Bor deaux. A constant application of this solution should be applied at intervals of about 18 or 21 days, at a strength of 1-100 for pip fruits; 1-125 for stone fruits. These applications arc very necessary to prevent the germination of fungi spores which may have survived the control Bordeaux applications. As the season advances chewing or eating insects make their ap[K.'arance in the orchard, the most troublesome of these being codlin moth, leaf roller, caterpillar, bronze beetle, and pear slug. These pests obtain their food direct from the fruit or foliage of the trees. They are comparatively easy to control if such fruit or foliage is kept covered with a film of poison ; for this purpose use arsenate of lead, at a strength of 31b paste, or jib powder, to 100 gallons water. The first flight of codlin moth occurs very early in the season, the moth laying her eggs at this period in the calyx of the apple or pear necessitating the first application of arsenate of lead when 75 per cent, of the petals have fallen, or before the calyx closes. Applications must be applied at intervals of 18 to 21 days; not only must the fruit be covered with this poisonous compound, hut every portion of the tree, thereby protecting such portions as are liable to- attack from any of tho various eating insects. When desired the following sprays can bo use*d in combination subsequent to tho calyx application of arsenate of load Arsenate of lead and lime-sul-phur solution; arsenate of load and black loaf 40; arsenate of load lime sulphur, and black leaf 40. This is often done as a time and labour saver* although the risk of russetting the fruit is much greater. Caro must he taken when combining arsenate of lead with lime-sulphur. It is advisable to make a heavy dilution of both before mixing To ensure maximum safety against damage to foliage add a dilute solution of limo to the arsenate, using approximately the same weight of lime as arsenate of lead. In every ease spray in-g must bo thorough; use a fine nozzle with force sufficiently strong to drive the solution into every corner and crevice of the iron ,