ON METHODS OF PREVENTING INSECT ATTACK 51 



My suggestion for destroying these pests is to attack them when in their 

 quiescent stages, and to attack them with fire. I would run a leaf fire 

 through the infested forest and take care that it was kept a leaf fire, cutting 

 down areas of long grass or fire-tracing them. 



In the days before the Forest Dt^partment, and for some considerable 

 period afterwards, there was no fire protection. The annual fires did a great 

 deal to keep the insect pests in check. These pests now breed unhindered 

 from year to year, and the only possible outcome must be severe visitations. 

 Instances of such may be quoted. Deodar areas in pxirts of the Western 

 Himalaya are defoliated year after year. Areas of sal are completely 

 defoliated or the tree is infested for several years together by a scale like the 

 Monophlebus, and nothing is done to endeavour to diminish the pests or deal a 

 heavy blow at them when they are really numerous. 



That fire is effective two instances would seem to prove. With the 

 permission of the Conservator (Mr. B. B. Osmaston), Mr. R. C. Milward had a 

 small area in the Garhwal forests, in which the sal Boarniia w'as pupating, fired 

 for me in May igo8, and sent me the materials in the way of larvae, pupae, 

 etc., collected after the firing. I examined the mass carefully, and was of 

 opinion that the firing had resulted in practically killing off the majority of the 

 pupating caterpillars— and they were in thousands in the soil, or on their way 

 there from the trees overhead, at the time of my visit. Those which appeared 

 still to have some life in them and the pupae came to nothing, and not a 

 single moth issued. A week or two later in that year I was at Horai in the 

 Kumaun Division. A fire of some severity had overrun three compartments 

 just previous to my arrival. I made a careful examination in the burnt area 

 for pupating caterpillars, and also ascertained the result of the fire on the 

 cockchafer grubs. I found no instance of a living grub or larva in the soil, 

 though my men and myself took numbers of dead and often charred ones. 

 The fire had not killed nearly mature cockchafer beetles, which proves 

 how necessary it will be to fire, if fire is made use of, when the pest is in 

 its larval or pupal stages. These stages will be known from its life 

 history. 



(4) Root-feeding Insects. — I have already dealt with root-feeding grubs 

 in the forest. In the nurser}- and in patches of sowings in the forest and 

 in plantations there are one or more methods of destroying them which may 

 be tried. In the young conifer nurseries and sown areas in the Himalaya 

 (deodar and cryptomeria), in the babul plantations in the United Provinces 

 and Berar, in those of poplar in Baluchistan, and in casuarina plantations 

 in Madras, trouble has been experienced from the attacks of both internal 

 and external root-feeding insects. In the former class comes the Coclostcrna 

 longicorn in babul (fig. 8) and the Trochilium caterpillar in poplar, whilst in 

 the latter are the Melolonthinae (see pp. 77-81), the Elateridae (p. 230), and 

 the A gratis cutworm. Crickets also occasion harm, Bnichytynpcs achatinus 

 having destroyed Ficus elastica seedlings in nurseries. These latter insects 



D 2 



