New York Agricultural Experiment Station. 459 



It may be stated, however, that in some sections of the State this 

 species of woolly aphis is doing very serious injury every year 

 both in the nurseries and young orchards. The insect and its 

 work are illustrated at Plate XXIII, figs. 1 to 5. All of the 

 photographs for this plate were made from an infested apple 

 tree taken from a nursery at Geneva. The insect works on both 

 roots and branches. Those infesting the former are referred to 

 as the root inhabiting form and those on the branches as the 

 aerial form. The injury to the roots caused by the lice is shown 

 at Fig. 3. The larger roots are more or less deformed and are 

 covered with galls. A nearer view of some of the galls is shown 

 at Fig. 4. Fig. 1 shows the appearance of a badly infested twig. 

 The lice collect on the under sides of the limbs and twigs and 

 secrete a bluish white cottony substance which completely covers 

 them. If these lice are removed it will be found that they have 

 formed numerous galls and pits on the bark. At Fig. 2 one of 

 these galls and some of the lice, with most of the cottony sub- 

 stance removed, are shown enlarged to about four times natural 

 size. 



The lice are distributed in the nursery or orchard by means of 

 the migrating females, but they are distributed over the country 

 by means of infested nursery stock. Many trees with infested 

 roots are shipped, but the lice are frequently found in the scars 

 along the trunks of the young trees as shown at Fig. 5. The 

 lice hibernate in these scars and other similar places on the 

 trees. The winter eggs may also be frequently found among 

 these hibernating lice. In a large majority of cases the infested 

 trees found on the packing grounds during the past two seasons 

 by the writer, were harboring the lice in these scars on the 

 trunks only, very few of them having infested roots. It is im- 

 por-tant that nurserymen and buyers take x^ains to avoid selling 

 or planting stock thus infested. The lice can be easily and 

 quickly killed by touching these infested scars with a cloth 

 saturated with kerosene oil. 



This insect is widely distributed throughout the United States 

 and is well known in Europe. It is probably found in this State 



