FUNGOID PESTS 



the winter, and the ground thoroughly drenched with a solution of sulphate 

 of iron. The solution may also be used for spraying in January or early 

 February, before the buds begin to swell. When the buds are expanding 

 the trees may be sprayed with very weak Bordeaux mixture. 



Fruit-tree Pustule, Eutypella prunastri, is a fungoid disease which attacks 

 young fruit-trees and nursery stock, Plum and Apple suffering most severely, 

 and Peach, Apricot and Cherry to a less extent. It is often abundant on 

 Wild Plum, Bullace, Blackthorn, &c. In the orchard it probably enters the 

 tree through wounds made by pruning. In the first stage there is a drying 

 up, browning, and shrivelling of the bark, and threads bearing conidia ooze 

 out through minute elongated cracks. These are followed in the second 

 season by larger transverse cracks or perithecia from which asci are produced, 

 each containing eight sporidia. These are ripe in late spring or early summer, 

 and carry on the infection. The fungus growing in the bark and cambium 

 must ultimately kill the young tree. All diseased plants should be burned, 

 and wounds on the stem should be coated with gas tar. 



Gooseberry Mildew, Microsphcera Grossitlarhc, forms white patches on 

 both sides of the leaves, giving them the appearance of having been sprinkled 

 with flour. The powder consists of myriads of spores or conidia, which, unless 

 destroyed, will rapidly spread the infection. When the disease is severe the 

 leaves die and fall early, hindering the development of the tree. Later in 

 the season minute black points are seen among the mycelium. These are 

 the globose receptacles, each furnished with 10-15 colourless radiating fibres, 

 and containing 4-8 sacs, or asci, each enclosing four or five sporidia. 



Being an epiphyte, the disease may be checked by the application of 

 sulphur, but the most effective treatment is spraying with a solution of 

 potassium sulphide. All dead fallen leaves should be burned in winter, and 

 the ground around the bushes should be well dug to bury stray spores. 



American Gooseberry Mildew, Sphcerotheca Mors-uvce, usually makes its 



appearance on the expanding leaf-buds, extending later on to the young 



wood and fruit. It has a cobwebby appearance, becoming white and powdery, 



and may be readily peeled off. In this country the fungus appears to be 



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