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that the tree may have put out after the rains. The emergence 

 holes left by the moths are frequently entered by ants, bees, wasps, 

 etc. The larvae of the 3rd, 4th and 6th generations pupate towards 

 the base of the hollowed shoot after constructing at least one silk 

 partition in addition to the cocoon. Larvae of the fifth generation 

 generally pass the winter without pupation in silken hibernacula. 

 The adult moths are rarely seen in flight and have not been observed 

 to feed. They hve in captivity up to 10 days. The average number 

 of eggs found in dissected females was 472, and these are laid singly, 

 attached to flowers, young fruits, and on developing leaves and 

 leaf-buds. 



The seasonal history of the insect as observed at Dehra Dun in 

 1914, 1915 and 1916 is given in detail. The life-cycles of the 3rd and 

 4th generations occupy from 17 to 19 weeks each and that of the 

 5th, or overwintering, generation from 28 to 31 weeks. 



Trees infested with Hypsipyla robusta suffer in two ways ; the 

 consumption of the flowers and fruits by the first two generations 

 amounts sometimes to complete destruction of the seed crop. In 

 the Punjab and Bengal it has occasionally been diflficult to collect 

 sufficient sound toon seeds for sowings, and in Austraha heavy seed 

 crops of Cedrela australis have been almost entirely ruined by this 

 borer. The injury to the growth of the tree, described above, is the 

 more obvious form of injury. It has been found impossible in India 

 to estabhsh young toon in plantations in the proximity of old toon 

 trees, and the same difficulty arises with mahogany and, in other 

 parts of the world, with various species of cedar. 



The pruning and burning of infested shoots on saphngs has been 

 found useless as a remedy. It is suggested that the simplest method 

 of estabhshing a sound plantation lies in the previous removal of all 

 old trees in the vicinity. Young trees are hable to attack from their 

 second or third year and the following measures are recommended 

 for their protection. As the flowers appear, the trees should be 

 banded with a strip of sacking about 12 in. wide and long enough to 

 overlap by 6 in. This should be tied with a cord at breast-height and 

 folded double over the binding-cord. These bands should be inspected 

 at intervals of not less than ten days during the flowering and fruiting 

 season and all larvae and cocoons destroyed. The removal of large 

 flakes of bark within reach and the cutting away of undergrowth at 

 the base of the tree will add to the value of the bands. About one 

 month after the fruits are ripe all infested shoots should be cut out 

 and burnt. In the case of bad infestations, a second pruning should 

 be done in the cold weather or three months before the normal flowering 

 date. Gaps in roadside avenues of toon should be filled up with some 

 other species. The extension of avenues, shade-trees, etc., should 

 be preceded and accompanied by sack-banding of the flowering trees. 

 The number of flowering trees it may be necessary to band in 

 order to protect a plantation varies. The width of the protective 

 zone is roughly estimated at 1,000 to 500 yards, but no experiments 

 have been carried out on the ffight of moths or the distance travelled 

 by migrating larvae. As many as 500 larvae may be found on one 

 examination of a banded tree. At the period of maximum abundance, 

 a cloth bag with draw-string and funnel-shaped mouth-piece is useful. 

 The contents of the bag should be emptied into a hole and buried. 



