These are enemies, and serious ones, though not insects. By rendering the tree foul they greatly impair its health. The Californian wash of caustic soda and pearlash, No. 11 in the list of washes, will be found the best remedy; and with a preliminary scraping by means of a piece of hoop iron even bad cases may be Cured. It should, however, always be remembered that lichen and moss are much the worst in cold, undrained soil.
Gardeners dread this pest, and well they may, for if once it gets a firm hold it is most difficult to get rid of. An early attack is of the greatest importance. Vigorous syringing is very good practice, for so simple a thing as cold water has its effect if applied hard and often. As an insecticide, see No. 5.
This tiny pest causes trouble with more than one class of fruit, both under glass and in the open. It worries the Grape grower, and gives the Gooseberry cultivator many an anxious hour. It thrives in an arid atmosphere, and does its worst when the plants which it is attacking are in difficulties owing to drought. Moisture is a great help in keeping red spider in check. With a moist, buoyant atmosphere under glass it has very little encouragement to spread. In the garden a deeply worked soil, kept loose on the surface, is of advantage, because it holds moisture. Mulchings of manure are also good. For a wash, see No. 5.
This fungus attacks both leaves and fruit. As in the case of so many other pests, the encouragement of healthy, wholesome, vigorous growth is the best preventive. Should the disease appear, attack it early with No. 7 or No. 8.
A, small scabbed Apple, natural size, showing a, black spots; b, depressed brown or black patch with cracks; c, point of advance by Fungus, prostrate hyphoe or mycelium beneath the skin of fruit.
B, section of a bit of the fruit tissues where the skin was broken through by the Fungus, showing d, skin (epidermis) turned up; e, spores of Fungus (Fusichadium dendriticum) in position; f, mycelium of Fungus; g, cells of Apple.
C, leaf of Apple tree, natural size, showing h, black dots and blotches caused by Fungus.
D, Fungus broken through membrane of Apple tree leaf: i, spores; j, mycelium.
E, small scabbed Pear, natural size, showing depressed patch caused by Fungus, with scabbed places where this has broken through the skin.
F, the Pear Scab and Croaking Fungus, Fusichadium dendriticum or pyrinum: l, spores; m, mycelium.
There are several forms, all dangerous. Lime washing the trunks of trees (No. 2) is a good and inexpensive plan. As destroyers, try (1) dabbing with a small brush dipped in methylated spirit, (2) syringing in winter with water heated up to 160° to 180°, (3) "soaparite," No. 1. With respect to (1), the plan is only suitable to small infestations and careful workers.
A particularly lively and troublesome enemy, attacking a great many different crops. A splendid remedy will be found in No. 6. In this and every other case attack the pest before it has assumed overwhelming proportions.
In the following list of the principal pests attacking the different fruits no pretence is made to give an elaborate essay on each, but concise hints are given embodying preventives and remedies.