20 REPORT ON INJURIOUS INSECTS FOR 1904. 



sulphur and soot, which should be applied in the early morning 

 when the dew is on the leaf. 



All cruciferous weeds, such "as" Charlock, Shepherd's Purse, 

 etc., should be destroyed, for on such the beetles breed and feed 

 before the young turnips appear. 



WIREWORMS. 



One of the most insidious pests infesting field crops, are 

 the larvae of certain beetles commonly termed wireworms. The 

 term wireworm, has, unfortunately, been misapplied to certain 

 other animals, the millipedes. The true wireworms are the 

 larvae of certain beetles popularly known as Click Beetles or 

 Skip Jacks. They may readily be distinguished from the milli- 

 pedes by the presence of three pairs of legs, one pair to each of 

 the first three segments behind the head, in addition to these 

 they have an anal foot on the ventral surface of the tail. 



The eggs are deposited in the earth or on the plant close to 

 the earth, from these the larvae hatch out in about four weeks. 

 They remain in the larval condition three or more years, seeking 

 the deeper layers of soil during the winter. When full-fed they 

 descend into the soil and construct a small oval cocoon, changing 

 into the pupae during July or August. In about three weeks time 

 the beetles emerge, and often remain in the ground until the 

 following spring. 



Many complaints have b^en received of really serious damage 

 done by these larvae. A Shropshire correspondent writes "they were 

 never more numerous, in certain fields there must be millions." 

 In this particular case I found on making inquiries, that mustard 

 and rape cake had been largely used in previous years. This 

 does considerably more harm than good. It no doubt attracts 

 the larvae, which feed upon it, and so allows the plants to grow, 

 but with a liberal supply of such food the wireworms flourish, and 

 the condition the following year is still worse. 



No effective remedy is yet known of treating these pests on 

 large areas. (0- Professors J. H. ComstockandM. V. Slingerland 

 in 1891 published the results of three years experimentation ( 2 )> 

 and the latter re-issued the same in 1896 in a condensed form, 

 bringing the information up to date. These experiments may 

 be considered under three heads, viz., i. Protection of Seeds ; 

 ii. Destruction of the Larvae ; and iii. Destruction of Pupae and 

 Adults. 



i. Protection of Seeds. Coating the seed with Paris green and 

 flour, and also with tar were tried ; soaking the seed in a saturated 

 salt solution, in a solution of copperas (sulphate of iron), in chloride 

 of lime and copperas solution, in kerosene oil, in spirits of turpen- 



i Mr. G. F. Strawson informs me that he used " Vaporite " with complete success for wireworms, 

 slugs, etc. 



2. Cornell Cniv. Agric. Exp. Station, Entomol. Div., Bull. No. 33, Nov., 1891 and Bull. No. 107, 

 Jan., 1896. 



