204 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 



Throughout the summer and autumn the chafer grubs seemed to 

 feed from the points of the roots upwards to about i inch from 

 the surface of the ground, but we got more at from 3 to 4 inches 

 from the surface than at any other depth. 



One Sunday towards the end of August, while walking in the 

 nursery, I noticed a 2-year i-year Scots pine transplant in Break 

 I. making part of a revolution on its axis and then returning. 

 This motion was kept up until, by digging the earth from the 

 stem of the plant with my penknife, I discovered a chafer grub 

 at a depth of 3 inches with the stem of the plant between its 

 mandibles. The root was completely severed from the stem just 

 below that part, but it must have taken a considerable amount 

 of energy to turn and re-turn the plant, which was not a large one, 

 in 3 inches of soil. 



In November, while lifting 2-year i-year larch, we got a 

 number of grubs at a depth of about i foot from the surface. 

 Once, in September, while bastard-trenching the break w^hich 

 had been in tares for the following year's seedlings, one of the 

 men noticed a vertical burrow, and following it downwards, got 

 a fully-developed male chafer at a depth of 18 inches. 



August I found to be the month in which most damage was 

 done by the grub to the roots of the plants. 



With large plants, say of 2-year i-year and over, the most 

 economical and at the same time the most effective way of expos- 

 ing the grubs is to lift the plants wholesale and transplant to 

 ground free from the pest, choosing for this operation, when 

 possible, showery or wet weather; and with good luck the 

 plants may be none the worse for the unseasonable removal. 

 I also tried trapping with potatoes sunk below the surface of 

 the ground, and examined once a day. By this means we 

 trapped over two thousand wire-worms which were destroying 

 seedlings, but these potato traps seemed to be a failure so far 

 as the capture of chafers was concerned. Another plan, which 

 was also a failure, was to lay willow rods with sappy bark below 

 the surface of the ground and between the lines of plants. 



The following, applicable to i- or 2-year seedlings recently 

 lined out in the break, was the most successful plan tried. 

 Towards the end of May 1903 I noticed that in the case of 

 2-year i-year plants and upwards, the chafer grubs invariably 

 confined their attack to the rind of the roots, injuring the woody 

 part but slightly. In the case of i-year and 2-year seedlings, 



