GEOMETERS. 



1 . "When the caterpillar is still in the buds 

 it must be left to the bullfinches and titmice, 



human exertions fail to effect any consider- 

 le diminution of its numbers. It is not, 

 however, to be supposed that bullfinches only 

 ick off those buds which are infested with 

 ese caterpillars: the contrary is most 

 suredly the case, and a little company of 

 ese pretty birds they travel in little com- 

 ities of four, five, or six will not unf requently 

 ttle in a gooseberry bush, or plum tree, and 

 ot leave it until half the buds have been 

 picked off. It is a remarkable fact, and one 

 that I have repeatedly verified, that scarcely 

 half of the buds thus destroyed are eaten ; the 

 remainder may be observed scattered on the 

 ground beneath. When the caterpillars have 

 emerged from the bud, fed for some fortnight 

 or three weeks, and are nearly full grown, 

 shaking or striking the trees with a stick will 

 cause them to fall to the ground, or to hang 

 by a thread. "When on the ground they can 

 be crushed under foot, or caught in cloths and 

 ed. Before shaking the tree some per- 

 ns daub the stem near the ground with a 

 sticky mixture, or pour coal tar on the ground 

 round the stem, to cut off their escape, as they 

 etreat : a good plan where the trees stand 

 one, but of little service where there is an 

 ndergrowth of gooseberry or currant bushes, 

 the caterpillars will ascend them. 



2. Little can be done against the insect in its 

 rysalis state. Digging the ground under 

 e trees in August has theoretical advantages : 



it displaces the chrysalis from its self-selected 

 habitation, and subjects it to the chance of 

 more or less moisture than is congenial to 

 its nature : and breaking up the soil exposes 

 it to the attacks of beetles, earwigs, and birds, 

 all of which feed upon it. Several years' 

 experience has failed to show much practical 

 benefit from' the process. It can only be 

 recommended as auxiliary to other means of 

 destruction. 



3. The third campaign is the most important. 

 The female moth, having no wings, is com- 

 pelled to climb the tree to deposit her eggs, 

 and may be caught by a sticky composition 

 placed in her path. 



In Germany this is done by surrounding 

 the stem with a four-sided box about twelve 

 inches high, the lower end of which is fixed 

 in the ground, and the upper end coped. Tar 

 daubed every few days on the outside qf the 

 box, below the coping, catches the females in 

 their ascent. This box plan was found to be 

 expensive for thickly-planted orchards, so it 

 became important to get a composition which 

 might be applied directly to the stem without 

 injury to the tree. Various things were tried, 

 of which Stockholm tar and cart-grease mixed 

 in equal proportions proved to be the best. 

 This compound remains sticky four or five 

 days, and the experience of eight years shows 

 that it does no material injury to the trees if 

 applied in November and December, the period 

 when the moth is out ; but applied in the 

 warm weather of April and May it has proved 

 destructive in many cases, probably from its 

 greater fluidity in the latter case, allowing the 

 tree to absorb it prior to drying. 



The composition rather tightens the bark, 

 which should therefore be slit the next sum- 

 mer, but in other respects does no injury that 

 can be perceived, even when trees are cut 

 down and split open ; and the growing bark 

 sliced off with a knife is the same colour where 

 the daub is applied as in other parts. It may 

 be employed without fear, but where fear does 

 exist, a coat of whitewash made of whitening 

 and glue size applied before the daub will 

 afford additional safety, as thick grease will 

 not penetrate glue. 



From the 20th of October to the 20th of 

 December, the gardener should examine his 

 plantation every evening with candle and 

 lantern, and destroy by hand all the moths 

 within reach. The couples are mostly on the 

 stem or within reach, and very visible. If he 

 find the moths numerous and sometimes 

 they are (the men say) as thick as bees he 

 should the following day daub his trees with 

 a ring of this composition round the stem or 

 branches in the most convenient places, taking 

 care to leave no other path to the tree, such 

 as side shoots, or contact with the branches of 

 other trees, for the ascent of the female. By 

 this means hundreds, nay thousands, of females 





