Gardeners’ queries

Press, Volume CXI, Issue 32660, 16 July 1971, Page 11

Gardeners’ queries

Could you give me a reason for the black coating on my manuka trees and the best thing to eradicate it?—H. H. (Christchurch). This deposit is known as sooty mould, a fungus which manifests itself on the honey dew excreted by some aphides and species of scale insects, the latter being the probable cause in.this case. Spray with white-oil. More than one spray will most likely be necessary.

One of my apple trees has been doing rather poorly during the season. In pruning it I noticed much of the woofl appears rather pimply on the bark

and many of the tips look dead. Could you offer any explanations? T. S. (Christchurch). The twigs are very heavily infested by San Jose scale and their sap-sucking mode of feeding would account for the general lack of vigour of the tree. If left unchecked these pests can cause the ultimate death of the tree. These scales together with oyster shell scales have been found to be very prevalent on local garden apple trees. Control consists of spraying all parts of the tree with either winter (red) oil or lime sulphur.

Could you, please shed reason as to why a Camellia sasanqua Hiryu loses all its buds at present? The plant is several years old and appears quite healthy. —P. P. (Christchurch). This problem is quite prevalent with many camellias and generally a physiological factor is involved. One of the most likely causes is dryness at the roots; frost damage cannot be excluded as the possible cause.

Gardeners’ queries should be addressed to Mr M. Lusty, 32 Brockworth Place, Christchurch 1. Any specimens sent for identification should be securely wrapped, to ensure that they arrive in a recognisable condition.