3f)6 EXPERIMENT STATION RECORD. 



The pine geometer moth (Fidonia piniaria), R. S. MacDougall 



(Trans. Highland and Agr. 800. Scotland, o.ser., 9 (1896), pp. 106-123, 

 figs. .-?). — This is an account of a study of the ravages in the Bavarian 

 forests near Nuremberg in 1895, of the pine looper or pine geometer moth, 

 whose caterpillars defoliated the trees, caused their death, and neces- 

 sitated the felling of millions of Scotch pine. The characteristics of 

 the Geometrida? and of this particular species are described ; and its 

 distribution, food plants, and habits considered, as well as the remedial 

 measures. The moths are reported as frequenting plantations of very- 

 young trees, and as laying from 58 to 66 eggs in a row on the inner 

 side of the pine needle in June. The eggs hatch in from a fortnight 

 to 3 weeks. The young caterpillars gnaw the surface of the leaf here 

 and there, but the older ones attack the needles at the edges, generally 

 near the apex, and work downward, leaving patches here and there and 

 the midrib uninjured. The larvae finally make their way to the ground 

 and pupate in the moss or litter of fallen needles, often in numbers as 

 great as 313 to 771 per square yard. 



Defense against the pest, once it has begun its work, is difficult. 

 The eggs being laid high, burning the branches might have some effect; 

 the attraction of the moths by electric lights is helpful, as also the use 

 of sticky bands about the trunk of the tree for the larva? which may 

 chance to fall and try to reascend. The method of shaking caterpillars 

 from the trees is valueless, since the larva? cling tightly to the leaves, 

 and also since it is somewhat injurious to small trees. The best plan 

 is to attack the pupse, and this may be done by leading swine to the 

 infested areas and supplementing their rooting by collecting. The 

 larva? may be raked out of the forest and burned, but this will not 

 destroy all the pupa?, for from an extended series of countings it has 

 been estimated that 35 per cent of the pupa? are to be found in the moss 

 and fallen needles, 60 per cent in the humus, and 5 per cent in the 

 mineral layer of the soil. Further, the author points out that consid- 

 erable help is received from nature in the form of weather influences, 

 insectivorous animals, birds, and in sects, as well as the fact that mixed 

 forests tend to discourage attacks. In addition, the author considers 

 briefly the predisposition of the weakened pines to attack from injurious 

 beetles, the chances of recovery after defoliation, under which head he 

 points out that, inasmuch as the insect is a late feeder, a moderate 

 destruction of needles is not fraught with very serious results, but that 

 when taken into consideration with other unfavorable circumstances 

 thousands of trees may be killed, as in the case of Nuremberg forests in 

 1895. 



Finally, there are considered the lessons of the devastation at Nurem- 

 berg, under which head he points out that remedial measures must be 

 started in the beginning of a plague, and that for the carrying out of 

 this principle a knowledge of insects and of their habits is absolutely 

 necessary. 



