PINE-SAWFLY. 75 



fifteen years are sometimes attacked. Specimens can commonly be 

 taken upon still older trees, and they will probably attack any tree 

 the lower branches of which are not more than seven feet from 

 the ground, above which height they do not ascend. They cannot 

 injure old bark, and the damage done to trees above ten years old is 

 usually insignificant. 



The preventive treatment of this insect consists in keeping the 

 ground as free as possible from unbarked logs and trunks, heaps of 

 rubbish and of sawdust, and in preventing egg-laying in the stumps of 

 recently-felled areas. This is done by barking the exposed parts of 

 stumps, earthing them over and beating down the earth, or by washing 

 them with an arsenical wash either of sodium arsenate, Paris-green, or 

 London-purple. Young plants can be protected by surrounding the base 

 of the stem with dry earth beaten flat with the spade, or with gas-lime or 

 similar compounds, or by " grease-banding " the base of the stem, and in 

 the case of Spruce, by planting with them a few Pines, which will be 

 attacked in preference. If the area planted is clean, beetles can be 

 prevented from entering it from outside by surrounding it with dry 

 trenches with vertical sides about a foot deep. Into these they drop, 

 and can be collected in large numbers, especially if brushwood be 

 placed at the bottom. 



Fissodes. Two insects which somewhat resemble Hylobius abietis 

 deserve passing mention ; these are the beetles of the genus Pissodes, 

 P. pini and P. notatus. Both occur chiefly in the North of England 

 and Scotland ; but P. notatus is likely to occur in any artificially- 

 formed Pine plantation if the young trees have been imported from a 

 locality which it frequents. Neither species is very common, but 

 P. notatus at least has been reported as injurious in Scotland. The 

 weevils are smaller than Hylobius abietis, more variegated in colour, and 

 the thighs are not toothed. They lay their eggs on Pine trunks, and the 

 larvae feed under the bark where they hollow out pupal chambers. 

 P. notatus attacks young trees from three to six years old, P. pini 

 older trees. The injury caused by both is to be met by careful 

 removal of attacked trees and others which, being sickly, are liable to 

 cause attack, and by selecting sites for nurseries so that the trees 

 shall enjoy good general health. They do most mischief to Pines 

 planted in unfavourable situations. 



Pine-sawfty. As the trees grow up they suffer less from Hylobius 

 abietis, but new enemies arise, especially defoliating larvae. In Great 

 Britain, the most important of these are the Pine-sawflies, Lopliyrus 

 pini and other species of similar habits. The females in late spring 

 cut a longitudinal slit in a Pine-needle and lay in it from ten to 

 twenty eggs, repeating the process on the adjoining needles till about 

 120 eggs have been deposited. The larvae hatch in a fortnight or 

 rather more, and live together in small companies on Pine-shoots, 

 feeding 011 the needles, from the midribs of which they strip away 

 the sides. They fortunately confine their attacks to the older needles, 

 and not to the young ones of the first year. Towards the end of 

 their two months' life they devour the needles completely, disregarding 

 the mid-rib. They are caterpillar-like, with twenty-two legs, and are 

 somewhat variable in colour, being usually lighter or darker green, 

 darker along the back, with a blackish head and a lateral series of 

 black spots. After five or six moults each larva makes a very small 



