50 



In the case where the one insect attacks both trees, I will only 

 mention it once, as the remedy would apply to either of the trees. 

 1 will divide the insects into two sections : 



1. Sucking Insects. 



2. Biting Insects. 



I will take the former first, which need " contact washes." 



INSECTS ATTACKING THE APPLE TREE. 

 " SUCKING INSECTS." 



i. WOOLLY APHIS, Schzioneura lanigera. ORDER RHYNCHOTA. 



This insect is also known as American Blight and the Apple Root 

 Louse. It is called the former name wrongly, as the insect is of 

 European origin. 



It is mostly seen in old and neglected orchards, but unfortunately 

 it is often seen in newly-planted orchards on account of its being sent 

 out with nursery stock. 



Its dispersal is by the wind, but it has now become a cosmopolitan 

 pest on account of dirty stock being sent out by nurseries. 



The pear tree is also attacked, the young material being generally 

 the most infected. 



It is easily recognized by white cottony threads fastened to the 

 limbs of the trees, this substance being excreted from glands by the 

 old and young females. 



Trees with a soft rind are most affected, and apples on the crab 

 stock resist this pest more than on the paradise stock, Northern Spy 

 and Winter Majetin being very resistant to its attacks. These aphides 

 pierce the bark with their rostra and suck the juices from the tissues 

 below, finally making the bark to split, this often being the fore- 

 runner of the canker fungus, Nectria ditissima. 



They are seen on the main trunk, the branches and the roots, and 

 only in an overwhelming attack are they seen on the leaves. 



The genus Schizoneura, to which this aphis belongs, is distinguished 

 by the nerves or veins on the wings. In this aphis, the chief vein of 

 the fore wing gives off three branches, and the branch furthest away 

 from the insertion of the wing forks into two. Also this aphis is 

 devoid of cornicles situated on the abdomen, as in certain other 

 aphides. 



There arc to be seeii four forms in a year : 



1. Wingless females which produce young by a process of " budding." 



2. Winged females doing the same. 



3. Males without wings which pair with 



4. W T ingless egg laying females. 



The wingless, viviparous females are oval in shape and purplish- 

 brown in colour, having reddish-brown or black antennae and legs, 

 both of which are very short. These females can be seen almost all 



