230 PROTECTION AGAINST INSECTS. 



iv. The fellinj^-areas should he rapidly cleared of all refuse, 

 and all sickly and dominated undergrowth should he removed 

 before the area is planted up, as such growth affords very 

 favourable shelter for the weevils. 



V. It has been proposed by Heyer and other authorities 

 that planting should not be attempted until one or two years 

 after the felling. By this time it is hoped the remains of the 

 roots will have dried up and become unsuitable for breeding 

 places. Dr. Hess considers that this involves too great a 

 sacrifice of time and interest on capital, even if it avoids the 

 necessity for replacing 50 per cent, of the plants, and also 

 that the consequent deterioration of the soil entails more 

 expense than the cost of replanting the failures. He estimates 

 that an interval of at least 3 years, instead of 1 or 2 years, 

 is requisite to cause the roots to dry up and become incapable 

 of serving any longer as breeding places. 



vi. Strong transplants should be used, together with 1 to 2 

 years' temporary field crops. Ball and mound planting are 

 recommended, and Nordlinger prefers autumn planting, as the 

 plants are less liable than those put in in the spring to attacks 

 by the weevils. Temporary field-crops involve a thorough 

 working of the soil, and this requires complete eradication of 

 the roots of the former crop of trees. 



In Saxony, wherever there is danger of an attack of weevils, 

 sowing in patches is preferred to planting. 



vii. The plants may be dipped in a mixture of chalk and 

 water, up to half their length, before being planted. This, 

 near Coblentz, cost Is. Gd. per 1,000 plants and proved 

 successful. Plants in situ may also be dressed with cater- 

 pillar grease at the rate of 500 plants per day's work of ten 

 hours. The operator makes with his linger a small trench 

 round each plant, greases the stem and top of root, and then 

 heaps the earth again around the plant. 



viii. Broadleaved trees may be mixed with the conifers. 



ix. Sheep may be fed over the felling-area, as their 

 droppings are obnoxious to the beetles. 



X. Protection of insect-enemies : the fox, rook, crow, jay, 

 starling, etc. The Nematoid worm, Alhwionema ininiJnle, 

 is parasitic on this weevil. It lives in the abdomen of 



