200 MANUAL OF GARDENING 



branches, particularly where much exposed to sun. The dead and 

 sunken appearance of the bark indicates its presence. The round- 

 headed borer works in the wood of apples, quinces, and other trees ; it 

 should be hunted for every spring and fall. On hard land, it is well 

 to dig the earth away from the base of the tree and fill the space with 

 coal ashes ; this will make the work of examination much easier. 



The peach and apricot borer is the larva of a clear-wing moth. The 

 larva burrows just under the bark near or beneath the surface of the 

 ground ; its presence is indicated by a gummy mass at the base of 

 the tree. Dig out the borers in June and mound up the trees. At the 

 same time, apply gas-tar or coal-tar to the trunk from the roots to a 

 foot or more above the surface of the ground. 



The bronze birch borer is destroying many fine white birch trees in 

 some parts of the country. Its presence is known by the dying of the 

 top of the tree. There yet is no known way of preventing this borer 

 from attacking white birches, and the only practicable and effective 

 method so far found for checking its ravages is promptly to cut and burn 

 the infested trees in autumn, in winter, or before May 1. There is no 

 probability of saving a tree when the top branches are dead, although 

 cutting out the dead parts may stay the trouble temporarily. Cut 

 and burn such trees at once and thus prevent the spread of the insect. 



Bvd-moth on apple. — The small brown caterpillars with black 

 heads devour the tender leaves and flowers of the opening apple buds in 

 early spring. Make two applications of either 1 lb. Paris green or 4 lb. 

 arsenate of lead in 100 gal. of water ; the first when the leaf-tips ap- 

 pear and the second just before the blossoms open. If necessary, 

 spray again after the blossoms fall. 



Cabbage and caulijlower insects. — The green caterpillars that eat 

 cabbage leaves and heads hatch from eggs laid by the common white 

 butterfly (Fig. 295). There are several broods every season. If plants 

 are not heading, spray with kerosene emulsion or with Paris green to 

 which the sticker has been added. If heading, apply hellebore. 



The cabbage aphides, small mealy plant-lice, are especially trouble- 

 some during cool, dry seasons when their natural enemies are less 

 active. Before the plants begin to head, spray with kerosene emul- 

 sion diluted with 6 parts of water, or whale-oil soap, 1 lb. in 6 gal. 

 of water. 



