352 COMMON WEEDS 



and poured into the soft soap and paraffin emulsion. 

 After a thorough churning the mixture should be 

 applied to the trees at once by means of a spraying 

 machine. Such a mixture as this effectively removes 

 the Moss and Lichen from the bark of trees. It should 

 be applied in fine weather between the middle of Feb- 

 ruary and the end of March, when the trees are dor- 

 mant before the buds burst. This caustic soda wash 

 not only removes Moss and Lichen, but aids largely in 

 the suppression of insects and other enemies of fruit 

 trees. 



An improvement of the formula given above has 

 been recommended by Mr. S. U. Pickering, F.R.S. 

 (Director of the Woburn Experimental Fruit Farm), 

 and the new wash suggested should consist of : Sulphate 

 of iron, J lb.; caustic soda, 2 lb.; lime, i lb.; paraffin 

 (solar distillate), 5 pints; and water to make up to 10 

 gallons. (See Eighth Report, Woburn Experimental 

 Fruit Farm, 1908, p. 27.) 



Care is needed in the application of washes contain- 

 ing caustic soda and other alkalis, as these substances 

 have a deleterious or "burning" effect on the skin and 

 also damage clothes. The hands should be protected 

 with gloves (preferably made of rubber), and spraying 

 should take place on a calm day when the " spray " 

 will not blow on to the face and into the eyes of the 

 operator. The eyes may be protected with goggles. 



Ivy (Hedera Helix L.), which forms such an excel- 

 lent and beautiful covering for unsightly walls, buildings, 

 and houses, frequently occurs where it is riot wanted, and 

 becomes a weed which it is necessary to eradicate. This 

 must be done by cutting down and removing as much of 

 the Ivy as possible, grubbing out the roots, and thereafter 

 regularly removing any new growths that may appear. 



