ORCHARD WORK FOR DECEMBER.

New Zealand Journal of Agriculture, Volume 3, Issue 5, 15 November 1911, Page 419

ORCHARD WORK FOR DECEMBER.

W. A. Boucher.

Cultivation.

It is . most important that the soil of the orchard or garden should receive proper attention. This applies equally to districts where . December .is usually dry and to others where there is generally more or less rain. Thorough working of the soil is essential ; in the former case to destroy such growth of weeds and grass as may have followed the last cultivation, with a view .to the conservation of as much moisture as possible, and in the case of the latter to prevent the growth . becoming so. rank that the ordinary light orchard cultivator would prove valueless for its removal and render the use of the plough necessary.

Codlin-moth, Leaf-roller Caterpillar, Apple and Pear Scab.

Spraying for the control of codlin-moth will require the careful attention of all growers in districts infested with this pest, as, with warmer weather setting in, the moth will be on the wing in increasing numbers. The first spraying of the season always presents some- difficulties on account of the irregularity with which different varieties come into bloom, necessitating the spraying of some and passing-over of others for the time being. This difficulty should' be obviated at the second spraying, for, the blossoming period being over , and all fruit set, it should be possible 'to spray all apples and pears without distinction.

Growers may again be reminded that careful and thorough work is essential for the control of the pest. The underlying principle upon which successful spraying with arsenate of lead for the control of the moth depends should not be lost sight of. Arsenate of lead will not prevent the laying of the eggs by the moth or the hatching of the young grubs, so that prevention of infection can only lie in depositing a thin coating of poison on every part of every fruit, in order that the newly hatched grubs may find 'it impossible to penetrate the skin without taking, sufficient of the arsenate to cause instant death. Complaints are occasionally received that the use of brands of arsenate of lead known to be of standard quality and thoroughly reliable has not prevented infection. In such instances there can be no doubt that failure has been due to the method of . application and not. to any defect in the material used.; in fact, in some cases this

has been actually demonstrated by altering the method of application but making no change in the material. In many districts of the Dominion showery weather frequently prevails during this month. Frequent showers and a humid atmosphere. produce conditions especially favourable to the development of apple and pear scab, so that, in addition to previous steps that may have been taken to prevent infection, varieties known to be particularly subject should be kept under observation and sprayed with the Bordeaux mixture, 4-5-50 formula, if either of these fungi threatens to become troublesome.. As mentioned in the October issue of the Journal, 1| lb. of arsenate of lead should be added to the Bordeaux mixture in districts where codlin-moth exists, in order to save the trouble and expense of spraying for pest and fungus separately.

Bronze-beetle.

In some districts growers have found it difficult to keep bronze-beetle under satisfactory control, in spite of spraying freely with arsenate of lead. It will be found that the addition of a small quantity of resin-solution will much increase the effectiveness of the arsenate of lead in preventing serious blemish to fruit through attack by this pest.

Resin-solution.

Proportions : 1| lb. resin, 1 lb. washing-soda, 2 gallons water. Preparation : Boil the water, dissolve the soda, add the resin, and continue boiling until the resin has thoroughly dissolved. Add about 3 quarts ,to each 50 gallons of arsenate-of-lead spray.

It is possible that in many instances the necessary treatment for the control of leech, mussel scale, red spider, scale on citrus trees, and pearmite may not have been carried out, or perhaps proved ineffective, owing to faulty methods of applying or preparing the spraying-compounds. In such cases it is not yet too late to adopt the lines of treatment suggested in the October issue of this Journal.

Irish Blight of Potatoes.

' It has often been the case that a main crop of potatoes has been suddenly attacked and destroyed by the Irish blight during the month of December, owing to climatic conditions prevailing which have proved exceptionally favourable to the rapid increase and spread of the fungus. Such conditions may recur during any season, so that to prevent possible serious loss precaution against infection should be taken by spraying with the Bordeaux mixture, 4-4-40 formula.

Tomatoes.

In some districts tomato crops will now be well developed and subject to attack by both fungus and caterpillar. An effective combined pre-

ventive of injury by either will be found in the Bordeaux mixture, 4-5-50 formula, to which 1| lb. arsenate of lead will be added. Spray at intervals of about three weeks.

Black-spot and Mildew of the GbapE.

Conditions that are favourable to the rapid' reproduction and distribution of parasitic fungi occur frequently during December in many localities. Constant care at this season is . therefore necessary to prevent attack involving injury to canes, foliage, and crop. Consistent spraying at regular intervals with the Bordeaux mixture, 4-5-50 formula, may be regarded as the only safeguard.