io8 Mites on Apple Trees. [may, 



The Board have received some specimens of apple bark 

 infested with a species of mite named Oribata lapidaria which 

 was stated to be damaging apple trees. 

 Mites on Apple These mites lay their eggs in crevices of 

 Trees. wood or on moss, fungi, and lichens, 



while other species of the family deposit 

 their eggs on the ground. From the egg issues a tiny larval 

 form with six legs, and after a few weeks in this stage the 

 larva moults. The stage succeeding this moult is known as the 

 nymph and is characterised by eight legs. The nymph moults 

 three times, increasing slightly in size with each moult, becom- 

 ing adult after the third change. The mites dislike bright 

 sunshine and readily shelter under moss and lichen. 



The best authorities on this family of mites, both in Great 

 Britain and America, hold that they do no harm to the trees. 

 A correspondent of the Board, however, who in 1904 sent 

 material from an apple tree similar to that lately received, 

 expressed the opinion, in spite of authorities quoted, that this 

 Oribata caused the destruction of his fruit-crop, causing the fruits 

 to wither and dry by eating round the root spurs. 



Treatment. — The mites may be destroyed by the application 

 of either of the following preparations : — 



(1) Soft soap, 5 lb. ; paraffin, 1 gallon ; and 40 gallons of 

 water. The soft soap should be dissolved in some boiling water 

 and the paraffin then added, the mixture being thoroughly 

 churned until a cream-like mass results. This " emulsion " 

 should be brought up to 40 gallons by adding water while con- 

 tinually stirring. 



(2) Caustic soda (98 per cent.), 2 lb. ; soft soap, \ lb. ; paraffin, 

 5 pints ; soft water, 10 gallons. The soap should be dissolved 

 in 1 gallon of soft water and the paraffin then added, and the 

 whole churned as in (1). The caustic soda should be stirred in 

 after dissolving in 9 gallons of soft water. 



In using (2), it should be noted (a) that it had better be used 

 before the buds burst, and (b) that as the spray is a caustic one 

 the operator should have his hands protected by rubber gloves. 



