SPRAYING FRUIT TREES FOR FUNGOID PESTS.

New Zealand Herald, Volume XXXII, Issue 9712, 7 January 1895, Page 3

SPRAYING FRUIT TREES FOR FUNGOID PESTS.

[BY L. HANLON, WHANGAREI.] (Continued.) Vines that; aro badly affected by black spot should have a winter dressing of sulphate of iron solution. The ingredients are :—Sulphate of iron 51b, sulphuric acid £lb, boiling water lgal. Place the greenstone in a wooden vessel, pour the acid oyer it carefully, then add the water very slowly. When dissolved, stir up, and ib is ready for use. After pruning and clearing up, and burning the cuttings and rubbish, paint the vines thoroughly with the mixture while warm. Very badly diseased vines thus treated have been almosb completely cured in one season. Root-fungus requires experimental work ; no cure is yet known. A good dressing of salt, 2 to 61b, according to the size of the tree, seems to prevent it from spreading to surrounding trees. Silver-leaf-blighb of plum, cause and cure are unknown. Collar rob of lemon and orange, cause and cure unknown.

In conclusion, I would Bay to get the upper hand of fungoid diseases a course of persistent spraying the first season must be maintained. One or two applications only is simply so much time wasted; afterwards two or three sprayings a year may suffice. Although nob a fungoid disease, the latest imported pest, peach-root-knot, should be mentioned in order that planters should be very careful in what they plant, as this is a deadly disease, and has already caused disappointment and loss to several growers here, and. is proving a most serious pest in some parts of California. It presents the appearance of large bumps on the roots at first, pinkish-white, or nob much harder to cub than a potato, afterwards growing hard and black. Then the tree dies. The cause of the disease is at present unknown. At first it was thought to be caused by microscopic insects known as nematoides, or eel-worms, but as they are not present it is now though to be a bacterial disease of the sap. At any rate, it is communicated to healthy trees by wounding the roots with spade or hoe after working about a diseased tree, or by buds from diseased trees, or even by the buddingknife having first cub a diseased plant then a healthy one. In California, ib is nob known to attack anything bub the peach, even the almond, the nearest relation to the peach, being proof againsb ib, but the little experience we have had of ib here would seem to indicate that the plum is susceptible of taking the disease. No cure is known. Young trees are killed by it almosb at once, old ones live for some years, gradually failing. California nurserymen who have a name to lose are using almond stocks more and more, or only selected peach stones from healthy seedling 1 trees, and never using peachstones from the canneries, as from such stones one is almosb sure to get the knot. It is to be hoped that New Zealand nurserymen will take the hint, and never use any Californian cannery peach-stones to raise stocks from.

While writing on the subject of fruit pests, it may be well to say something about two destructive insects which are becoming increasingly prevalent in many orchards, where they cause no small loss. The first I shall mention is that large green leaf-like grasshopper, known to many as the angularwinged katydid (Microcentrum retincrvis). This peat is becoming alarmingly destructive in orange groves. In the Whangarei districts lasb season it destroyed threefourths of the young crops in some plantations before being noticed. It eats the skin of the young oranges while they are about the size of small marbles. It likewise does a lot of damage to peaches, applet, etc., by eating large holes in the fruit and devouring the foliage. As a. remedy, I have tried Paris green at the rate of lib to 150 gals, water, with large shovelful of fresh lime added. In a few days this had destroyed all the katydids for • the time being. Others appeared later on, bub were easily cleared off in the same way. Several species of birds, such as yellowhammers, kingfishers, etc., devour these katydids. To thoroughly mitigate the pest, the Government Entomologisb ought to take immediate steps to introduce the natural parasite, which is a small chalcid fly, Eupelmus tnirabilis, Walsh. The eggs of this parasite are placed within the eggs of the katydid and destroy them. It is very common in Florida, whence parasitized eggs might be obtained through the American Department of Agriculture. When obtained, they should be placed in infested orchards, in boxes covered with coarse wire gauze, so that the parasites might escape without allowing the young katydids to do so. ■■' . . :.-' >' • - ■ ■'

The other insect is the small bronzo-beetle (Encolaspia brunea), by. many considered a worse plague than the codlin moth. It really does an immense amount of damage in many Northern orchards. In some I have seen it is so bad that to find an apple free from damage was quite impossible. lb also caused much damage to pear trees by eating the young growth all to bits, and also by nipping off the leaves on the young wood of plum trees. I have found much benefit from spraying with Paris green. As for codlin moth, at the rate of lib Paris green, a shovelful of lime, and 150 gals. water. It is rather difficult, however, to eradicate them from varieties by this means. Such thick clustering sorts as Irish peach shelter them to a great extent from the spray, and therefore it is well to take advantage of the habib the beetle has of falling from the tree when disturbed, to catch; and destroy ib. To do this, obtain sufficient lining boards, and fasten together in a square large enough to cover the ground beneath the branches of your largest)

trees. The square should be in two pieces, with a notch cub out of each where the trunk of the tree will come. Give the boards a good thick coat of gas-tar, and the apparatus is ready. Go to work by gently placing the tarred square beneath an infected tree ; then give each main branch a good sharp shake; a forked stick will greatly assist in reaching the upper ones. Down will fall the beetles and stick in the tar. Proceed in a similar manner with the resb of the trees. In two or three days go over the orchard again, and a third time a ' little later. This will usually suffice to clean out the pest for the season. Small trees may be cleared by shaking the beetles into an inverted umbrella and then emptying them into an old milk-pan, in which has been placed a small quantity of kerosene and water. Orchards which are kept well cultivated and free from grass and weeds 'suffer bub little from this pest.