REMEDIES FOR INJURIOUS INSECTS 249 



been ploughed, and may with advantage be worked into the 

 soil by the harrow or grubber. Two tons an acre are per- 

 fectly safe (much larger quantities have been used with good 

 results). 



Poisoned Bait 



Mr Marlatt (" Important Insecticides ") recommends laying 

 poisoned slices of potato or bunches of clover in fields or beds 

 infested by insects. The bait should be dipped in a strong 

 arsenical solution, or dusted thickly with a dry arsenical, and 

 renewed as soon as it becomes dry. This is said to succeed 

 with wireworms and surface-larvae. 



Weed Destroying 



Weeds in neglected corners are often nurseries for insect- 

 pests ; fallen trees harbour bark - beetles ; stubble and chaff 

 protect corn-ravaging flies during the winter. Prompt de- 

 struction of rubbish of every kind is a precaution of no small 

 value. Compost-heaps made-of weeds often become breeding- 

 places for insects, and when the heap is carted on to the 

 land as a top-dressing, the eggs and larvae are distributed as 

 well The heaps should be turned over now and then, so as 

 to prevent grass growing on them, and forming a shelter. 



Traps 



Slices of potato or turnip, and strips of canvas ("burlaps") 

 fastened round tree-trunks (p. 243), come under this head. 

 Wood-piles, old sheds, etc., are often excellent insect-traps, 

 and lodge many pupae; but, being nearly always left un- 

 searched, they favour instead of hindering the enemy. Rape- 

 dust is very 'attractive to wire-worms, and may be used as a 

 trap. 



Grease and Tar-Bands 



Fastened about trees, to prevent larvs ascending from the 

 ground (p. 242). 



Mechanical Disturbance 



Trampling, harrowing, rolling, rope - drawing, and sheep- 

 driving have been found effective where multitudes of msects 



