Garden Pests in Otago.

Otago Witness, Issue 2179, 28 November 1895, Page 8

Garden Pests in Otago.

The leaf spot on the cherry tree, Septona ceratiua, is a minute fungus, making its appearance on the leaves in yellow spots, afterwards developing into dark masses, which absorb the fluids, dry up the tissues, discolour the leaves, and cause them to fall prematurely. The fungus is propagated by thread-like, 6lender, minute sporidea, which get wafted to fresh lexves, germinate and bore into the tissues, making fresh spots. After the leaves fall tbe cherrits get stunted, discolour, and fall off. Tho cure which has been favourably spoken of is spraying the trees with a solution of lib of : bluestone to 20gal of water. This spraying ! should be dono before the buds unfold — when the leaves are about one-third grown. The trees should be sprayed with a solution of am- [ monia, curbonate of copper diluted with twice t the quantity of water used for tho first spr&y- ; ing ; thi3 to be followed by two further spray- , ings during tbe season. # ' The silver blighb, apple mildew (Oidium , farinosum). — This parasite attacks the tenderest terminal leaf shoots, flower buds, and , frequently expanded flowers, covering them with a greyish-white powder, giving the parts affected ( a frosted, silvery appearance. As the disease , progresses >all the tender parts become swollen, blistered, curled, and distorted, and in virulent • cases become bl ack. The effect produced is an imperfect pollenation, and the setting of the fruit is retarded, and what does set is more or less injured or destroyed. The oidium fungi is found to consist; of a mass of woven spawn threads, of a silvery-white colour, much resemj bling the finest part of a spider's web. They are furnished with minute suckers, which 1 pierce the leaves, suffocate the trees, and set ' up decay. The slightest breath of air will i separate the spores, which are all so potent , with life that they frequency germinate while . flying through the air, and invade any tree that 1 affords them a suitable habitation. Careful culture and clsanlines-i are naces- > sary to keep this pest in check. All pruuings - and fallen leaveß should be burnt, and the soil c around the trees forked over, and a quantity of some good fertiliser applied. Tbe tree 3 should be sprayed over before the blossom ' buds commence to swell wilh a solution of lib bluet tone to 30gil water, and after the blossoms have expanded thc-y should be sprayed 1 over with a Folution of Boz softsoap and 4oz s sublime sulphur in sgal soft water, thoroughly - dissolved and mixed. This will tend to arrest b the progress of the disease, and hslp to secure f the setting' of the fruit.— North Oago Times.