that many will not survive. In the nursery I have observed that some trees were practically immune, though growing side by side with others whose branches touched them and were covered with the Chermes ; but having marked these trees and watched them after they were planted out, I have not as yet been able toraeetiS myself that this immunity is permanent. Though I have not found this insect attack Japanese, American, and Siberian larches at Colesborne as severely as the common species, yet I have seen it upon them all, both there and elsewhere. Blandford’ says that washing the trees in April with a soft soap and paraffin mixture in hot water may prove effective, and suggests other forms of wash; yet it is evident that such remedies cannot be economically employed in plantations, and I know of no means of preventing the ravages of this insect ; though thin planting, mixing with hardwoods, and the avoidance of thin dry soils and damp shady situations are undoubtedly the best means of avoiding severe injury from this pest, as well as Peziza.
Leaf-Miner of the Larch.’—The only other insect that I know of which causes serious injury to larch in this country is a small tineid moth, Coleophora laricella. This is extremely prevalent almost every year in some of my own plantations having a south-west aspect, and has been supposed by some authors to be directly connected with the attacks of Peziza, which usually accompany or succeed it. According to Stainton the larva is hatched in the autumn, and at first feeds as a miner inside the leaves, and at the approach of winter retires to the stem of the tree, where it passes the winter without feeding. In the spring as soon as the leaves appear it begins to work, and frequently becomes so numerous that most of the buds have several leaves injured. In May it is fully fed, and attaches the case which it has formed for itself from the leaves of the tree to a twig, and appears as a perfect insect in July. The tree is undoubtedly very much weakened by severe and repeated attacks, which render it more liable to die from Peziza, but as far as I know there is no practicable remedy for it in plantations.
A new enemy to the larch which has recently appeared in the north of England was described in the Journal of the Board of Agriculture in 1906, p. 375, and more fully in a paper by Mr. J. Smith Hill.® This is the larva of a sawfly, Nematus Erichsonii, Hartig, which was first noticed about 1904 by Mr. Cyril F. Watson, of Cockermouth, and which has done considerable damage in the Lake district of Cumberland by defoliating the larch. Mr. Gillanders has recently found the larva near Rothbury, and Mr. Forbes in Chopwell woods, but I have not heard of its appearance in the south of England.
I am informed by Mr. R.D. Marshall, of Castlerigg Manor, that he has known periodical visitations of the same insect for several years, and that, owing to the late period of the season at which the larva appears, the trees have not suffered as seriously as they would if attacked earlier. He states that the plantation alluded to by Mr. Smith Hill first suffered from this cause as much as forty years ago, and has survived the attack in three consecutive years recently. It was noticed that during these
Journ. Roy. Hort. Soc. 1892, P. 170.
Cf. Gard. Chron. xxxvi. 181, figs. 70, 71 (1904).
3 Quarterly Journal of Forestry, i. p. 67 (1907).
