830 



Root Tumours of Sugar-beet. [Jan., 



(i.) Various substances have been tried upon the surface of 

 the bark, e.g., grease and paraffin, bone oil and paraffin, etc., 

 none of which, however, were more than partially successful. 



(ii.) Two experiments were made , with a view to prevent 

 the newly hatched larvae from entering the bark. In one case 

 the lower part of the stem was covered with pitch and gave 

 very fair results, whilst in a second case the pitch was mixed 

 with slaked lime, the two well worked together, and then 

 applied to the lower part of the stem with a stiff brush. Before 

 drying the whole of the surface was well dusted with lime. 

 This proved most successful, no larvae entering the bark. 

 Kollar (op. cit., p. 237) mentions that egg laying may be pre- 

 vented and the caterpillars prevented from entering the inner 

 bark, if the trees are washed about the end of May, and again 

 in September, with a solution of lime. 



(iii.) Where the larvae were known to be in the bark a mixture 

 consisting of one part of powdered napthalene and three parts 

 of clay were mixed together with water to the consistency of a 

 paste and the trees were smeared over to a height of between 

 two and three feet. This mixture was applied to the trees in 

 June and again in November. In the latter case the larvae 

 were particularly numerous, but no further trouble was noticed 

 after the mixture was applied. Any composition which will 

 adhere to the tree and make the surface obnoxious to the 

 moths will in all probability prevent egg laying. 



In the case of the trees I saw in Kent, many had had the 

 tunnels cut open and the larvae destroyed by hand, but this 

 constant cutting into the bark and sapwood undoubtedly in- 

 jures the trees, apart from disfiguring them and leaving 

 crevices for any stray moths to lay their eggs in. 



The methods described above are both cheap and effective, 

 and may prove of service to fruit growers who are troubled 

 with this undesirable pest. 



Specimens of diseased sugar-beet have recently been sub- 

 mitted to Kew for investigation, from Norfolk, where this 

 crop has been somewhat extensively 

 Root Tumours grown during the past season. The 

 of Sugar-Beet . roots bore large tumours or out- 

 growths, attaining in one instance to the 

 size of a cricket ball. These outgrowths, which vary from one 



