12 



THE REPORT OF THE 



No. 19 



Older to destroy the lice when they are hatched from the egg-masses and are 

 moving about in search of a final resting place. At this particular time they 

 are exposed and can be reached by spraying, but as soon as they attach them- 

 selves to the leaves and become covered with their scale they are practically 

 invulnerable. The Park Superintendent was instructed to try these methods 

 on selected trees and report results next year, but it was felt to be beyond the 

 power of the city authorities to deal with the immense number of shade trees 

 throughout the city, unless they were quite sure of exterminating the pest. 



By way^ of encouragement I mentioned to the Council that this insect is 

 well known in many cities in the United States, and the general experience has 

 been that after a few years of abundance it ceases to be numerous for a time 

 owing to the attacks of parasitic insects and the effects of atmospheric condi- 

 tions. It does not, as a rule, kill the trees, because its attacks do not strip off 

 the foliage nor entirely prevent the leaves from discharging their function, 

 though when so numerous as at present they must certainly impair the vigor, 

 if not the vitality, of the trees they infest. As an illustration of their num- 

 bers, I may mention that on a single maple leaf picked at random from a tree 

 r counted 707 scales on the under side and 72 on the upper surface. When we 

 consider the number of leaves on a large tree, the majority of which are in- 

 fested, the specific name innuTnerahilis seems most appropriate. 



There were several other insect attacks during the year that may be men- 

 tioned, but they did not attract public attentijDn. 



Fig. 6. May beetle . 1 pupa, 

 grab, 3 and 4 the beetles. 



the w lute 



White grubs (larvae of Lachnosterna or May Beetles) (Fig. 6), were 

 complained of in some cases both in Woodstock and London on account of the 

 damage they had clone to lawns by devouring the roots of the grass. As they 

 work underground and spend three years in the larval state, it is not easy 

 to prescribe a remedy. In the case of old pasture fields, where they sometimes 

 become very abundant, a simple remedy would be to plough up the sod and 

 turn in pigs or turkeys, and then to grow a root crop. Where lawns are badly 

 damaged it would be worth while to dig up the affected parts late in the 

 autumn and expose the grubs to the frost, or during the summer to remove the 

 tiod and soak the ground below with coal oil. Subsequently new earth could 

 be filled in and fresh turf laid. 



Wire-worms (larvae of Elateridcv or Click-beetles) were very abundant in 

 many market gardens in the neighborhood of London. As these creatures also 



