24 MONTHLY NOTES ON GRUBS AND OTHER CANE PESTS. 



some of the statements that appeared, inadvertently, in reporting last 

 mouth. As was then stated, it is still rather early to draw definite 

 conclusions, but the splendid appearance of certain fields, both at 

 Meringa and at Greenhills, is encouraging. 



Late planting (October) appears to be of considerable importance 

 for infested areas. If cane is regularly cultivated, the soil is actively 

 worked during the flight and oviposition of the beetles; and from 

 present observations this constant stirring of the soil either deters the 

 beetles from laying their eggs or, if they are laid, breaks up the egg- 

 chambers, which are only a few inches below the surface, and prevents 

 the hatching of the young grubs. At any rate, cane planted in October 

 this season is in very good condition in both of the above regions, even 

 though the fields are situated right in the midst of the infested areas, 

 Avith grub-destroyed cane immediately adjoining. 



By cutting these fields late, say next November or December, it may 

 be possible to ratoon them so as to again avoid an attack of the beetles, 

 for the ploughing and cultivation will coincide with their period of 

 ' oviposition. We are led to this conclusion from observations at Green- 

 hills, where certain fields, which were cut during last December, situated 

 right in the midst of the infested f;rea, have been successfully ratooned 

 with little apparent injury from the grubs. 



We had experiments planned for planting areas at Greenhills both 

 in November and December this last season, but a rush of cutting and 

 other work made it impossible to get in these experimental plots. Now, 

 however, since the October planting looks so well we are doubly anxious 

 to see the results of experiments in later planting on soils v/hich will 

 permit working during the rainy season. We shall be very grateful for 

 information from growers who have had any experience with late 

 planting as a means of grub-control. 



Though our experiments in summer fallowing were not as complete 

 a success as we could have washed in either of the districts noted above, 

 due to the rapid development of certain grasses upon the ploughed 

 ground, there was certainly a very decided decrease in the number of 

 grubs turned up by the ploughs in these plots, as compared with areas 

 that had not been fallowed. Undoubtedly, if the infested fields could 

 be well worked and kept clean during December, or through the period 

 of oviposition of the beetles, very lew eggs w'ould be laid in them, and 

 most of the resulting grubs would be destroyed by subsequent plough- 

 ing, preparatory to early planting. Eight along this line we recently 

 had an excellent letter from a grower, who claims that after suffering 

 from the ravages of the grubs for twenty-five years he has at last 

 succeeded in raising a clean crop by having his ground well worked 

 by December, preparatory to early planting. He states that he does 

 not tr}^ to ratoon on this infested land, for ratooning multiplies the 



