258 



THE TROPICAL AGRICULTURIST. 



[October i, 1884. 



the behaviour of the cockchafer grubs on those patanas I 

 which are believed to be their original homes. In 

 Europe the cockchafer grubs eo eat away tbe roots of 

 grass on swards and lawns, that the stems and the 

 surface soil in which they grew, could be rolled up, 

 as if separated from the earth below by a lawn-mower 

 or similar machine. We have never heard of the 

 insects doiDg anything like this in Ceylon, nor indeed 

 have we ever heard of pataua grasses being seriously 

 injured bv grubs, although their presence and pro- 

 pensities " become at once apparent when foreign 

 plants, such as cinchonas are placed on the patanas. 

 We know that when Mr. Elphinstone propounded 

 the theory now endorsed by Sir William Gregory, 

 that to the non-burning of patanas was largely 

 attributable the prevalence of grubs, a well-known 

 planter in Dimbula, possessor of large expanses of 

 patana, repudiated the idea. We should like to hear 

 him on the whole question, including the prospects of 

 tea culture on patana lands. It is important to know 

 that although some species of beetles, which hauut 

 coffee blossoms are not harmful, any more than bees 

 are, the cockchafers and the allied species of beetles, 

 should be destroyed wherever found, not only because 

 of the destructive grubs they propagate, but because 

 the winged insects themselves damage the flowers of 

 coffee and other plants by des'roying the pistils and 

 stamens and so preventing fructification. How far has 

 observation here confirmed this position of Mr. 

 McLachlan's. That naturalist effectually disposes of 

 the popular idea, not yet banished from scientific 

 works, that the "free-flying" life of the cockchafer 

 beetle is exceedingly ephemeral. We are sorry to 

 learn that their mischief-working lives are _ much 

 more extended than we imagined. Whether in our 

 hot climate the periods both of grub and winged 

 life, are not shortened is a question for solution. 

 We shall all agree that their continued existence in 

 any stage could well de dispensed with. And yet, 

 who can say ? in view of the mischief the man who re. 

 places forest by coffee is accused of doing by disturb- 

 ing "the harmony of nature." The cockchafer 

 " cneses" : the " notorious Mclolanlha vulgaris," 

 ' May bugs " or "dors" (not from dormancy by any 

 means, but from their humming), may be necessary to 

 the harmony of nature, however, discordant their notes 

 may seem to us. In that case Mr. McLachlan's final 

 recommendation, that a small experimental garden 

 should be established, in which the pests must be bred 

 in order to be observed, will not seem bo very 

 preposterous. Mr. McLachlan is utterly unable to suggest 

 any poison to which the beetles might be partial. Whis- 

 key toddy is too expensive to be tried, but an 

 experiment might be made with Paris purple, or red, 

 or green, mixed with coarse jaggery? 



Turning to Miss Omerod's "Manual of Injurious 

 Insects," we tiud the cockchafer associated with the 

 oak and described thus :— 



The Cockchafer, known as the May Bug, is injurious 

 both in the larval and perfect state. As a grub it feeds 

 under ground on the roots of grass, vegetables, and 

 young trees ; as a beetle it feeds on the leaves of Oak, 

 Elm, and other trees, sometimes entirely stripping the 

 foliage. The eggs are white or pale yellow, and are 

 laid (early in the summer) about six or eight inches 

 below the surface of the ground, the female burrowing 

 down to deposit them, and laying thirty or more, near 

 together amongst the disturbed earth. 



Tbe grubs are thick and fleshy, white or yellowish in 

 colour, with strong jaws, and three pairs of legs; and 

 usually lie on one side, somewhat curved together. 

 At the commencement of spring they come up 

 to within a few iuches of the surface of the ground, 

 where they feed on roots of growing plants ; and at 

 the end of the third summer, when full fed, they again 

 go down into the earth to a depth of two feet or 

 more, and change to pupie in oval cells. 



During the following winter they develop into the 

 perfect chafers, but do not come up through the ground 

 until the next summer, that is, the fourth year since 

 they were hatched, when they may bo found as early 

 as May hanging half-torpid or sluggish beneath the 

 leaves during the day, and coming out on the wing 

 during the evening, when they fly in search of their 

 mates or feed on the foliage of the trees. 

 Then come 



Prevention and Remedies. — When the May Eugs or 

 Cockchafers appear in the large quantities sometimes 

 recorded, as when eighty bushels are stated to have 

 been collected on one farm (' Encyc. of Agriculture,' 

 2nd ed., p. 1,100), it is worth while to beat or shake 

 them from the trees, preferring noon-time or early on 

 a bright warm day, when the beetles are clinging be- 

 neath the leaves and are dull and sluggish. 



They may be shaken down on to large cloths spread be- 

 neath the tree, or may be swept together and destroyed 

 taking care in either case that the chafers are collected 

 before they have time to recover from the fall and take 

 wing ; or, as pigs and poultry devour these beetles greedilly, 

 it would save trouble to drive them below the trees and 

 shake the chafers down to them, Poultry would take some 

 time about the work, but pigs would make a rapid and 

 effectual clearance. 



In field or garden cultivation, where many grubs are 

 turned up by the spade or plough, some means should 

 be taken for destroying them, Hand-pickiug by children 

 is of use, but probably in the fields the pigs would be 

 the better helpers. Their instinct and fondness for the 

 grub makes them hearty and well-qualified searchers. 



Wild birds, such as Rooks and Sea Gulls, should on no 

 account be driven off. The Black-headed or Peewit Gull 

 follows the plough in the same manner as the Kooks, 

 and feeds on cockchafers both in the grub and beetle stages ; 

 the Common Gull will go for miles inland to follow the 

 plough in search of insects and grubs ; and the Nightjar, 

 by " feeding almost entirely on cockchafers and moths " 

 during the morning and evening hours, is also of great 

 service. 



In pasture lands, where the grass has been seriously 

 injured by cockchafers grubs feeding 'on the roots, much 

 service has been done by Rooks turning up the grubs and 

 devouring them : in such cases the birds should be care- 

 fully protected from molestation ; they pull up little— if 

 anything — more than the infested plant (which would have 

 died), and are in this case almost our only means of clear- 

 ing off these large grubs, which otherwise excepting when 

 changing their skins or torpid during severe cold, would 

 continue feeding for three years. 



In garden cultivation, where the ground is in- 

 fested, a tame Rook is of much service. The bird will 

 set to work as soon as it is introduced, and keep on 

 steadily at the task, clearing the grubs from spots that 

 could not be reached otherwise without injuryto the plants. 

 _(W. S.) 



From the circumstance of the cockchafer grubs feed- 

 ing amongst roots and giving no signs of their presence 

 till the fading of the attacked plant draws attention to 

 the injury going forwards, it is difficult to find any re- 

 medy, excepting by means of the insectivorous birds, 

 which appear to have an instinctive knowledge of the 

 position of the larva below the surface ; but where ex- 

 amination of the roots of injured plants shows this grub 

 to be present, it would be worth while to try the effect 

 of good drenchings of some fluid, such as tobacco- 

 water (properly diluted), gas-water, fluid drainings from 

 pigsties, or anything else preierred that would not be 

 injurious to the plant, but would be sufficiently offensive 

 to the grub to drive it from the roots. — ('Brit. Birds, 

 ' Illus. Brit, Birds,' &c.) ' 



AVhen in Australia we visited a vineyard where 200 

 turkeys had been turned out to abate a plague of 

 grasshoppers. But tbe insects were on the surface of 

 the ground. Turkeys here are too expensive and delic- 

 ate for the purpose and we fear to propose even 

 flocks of common fowls, because of the objections 

 that if hawks or jackals did not attack then, they 

 would be speedily disposod of by Ramasami vulgaris, 

 who would probably plead the affinity of kuli with 



