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[Sbpt. mm. 



PLANT SANITATION. 



Entomological Notes. 



By E. Ernest Green, Government Entomologist. 



Specimens of tea leaves, attacked by the ' Ribbed Mite' (Phytoptus carnnatus) 

 and the ' Yellow Mite ' (Tarsonymus translucens) have been received from several 

 correspondents. Both these pests are readily amenable to the sulphur treatment. 



Another small outbreak of the ' Morawak-korale Nettle Grub ' (Thosea recta) 

 has been reported from tea in the Yatiyantota district, but the pest has been kept 

 in hand by prompt measures (the collection and destruction of the caterpillars). 



The ' Red Slug ' (Heterusia cingala) has put in an appearance on tea in the 

 Norwood district. 



Signs of ' Tortrix ' (Capua coffearia) have been observed in the Yatiyantota 

 district, but this pest does not seem to thrive at low elevations. 



I have reports of injury to the foliage of Cacao plants, in the Kurunegala 

 district, by a small species of Thrips (Physopus rubrocincta, Giard) which infests 

 the under surface of the leaves. The consequent fall of leaf interferes with the 

 proper ripening of the crop. Sulphur (as recommended for tea mites) will be found 

 a useful application. 



Examples of the large caterpillar of the ' Death's Head Moth ' (Acherontia 

 lachesis) hive attracted attention by defoliating young plants of 'Dadap' 

 (Erythrina). The caterpillars can be easily collected and destroyed by hand. 



The annual invasion of bungalows by the small hairy caterpillars of Azura 

 (Nepita) conferta has commenced. They have an inconvenient habit of concealing 

 themselves in hats, clothing and towels hung up to air. Such articles should be 

 examined and well shaken before being used. The resulting moths may now be 

 observed on the Aving. They are of a dull orange colour, the wings barred 

 with black. 



A somewhat alarming caterpillar pest of cinnamon is reported from the 

 Moratuwa district. About 40 acres are infested. A similar outbreak is said to have 

 occurred about two years ago when slaked lime was applied without success. It 

 was subsequently found necessary to cut down and burn the whole of the infected 

 cinnamon. If Paris Green had been mixed with the lime, in the proportion of 

 one part to six by weight (equal to about one to ten by measure), the loss of the 

 cinnamon might have been avoided. Arsenical preparations are the only effective 

 remedy for leaf -eating caterpillars. 



The caterpillar in question proves to be that of a common moth (Euproctis 

 fratema, Moore). It is of a dull brown colour, with a crimson head ; there are 

 short tufts of ochreous brown hair on the back, and longer greyish hairs on the 

 side of the body. The resulting moth measures from one to one-and-a-half inches 

 across the expanded wings which are of a bright yellow colour with some indistinct 

 darker bars and three small black spots on the outer margin. The caterpillar is 

 practically omnivorous and is widely spread, but does not usually appear in trouble- 

 some numbers. It is probably kept in check by Ichneumon flies, under ordinary 

 circumstances. 



I have been experimenting with a patent insecticide brought out by the 

 well-known Strawson's Co, (and supplied by their local agents in Colombo). It is 

 sold under the name of ' Vaporite,' and is designed for use against all subterranean 



