176 TREES IN- WINTER 



The lime-sulphur wash is the standard remedy for the control of 

 scale insects on fruit trees. It may be made up at home, but it 

 is disagreeable and exacting work. It may be purchased in con- 

 sentrated form at from twenty to thirty cents per gallon and 

 is ready for spraying after diluting it with eight parts of water. 

 In this proportion it is used only while the trees are dormant. It 

 has extremely caustic properties and corrodes and discolors every- 

 thing with which it comes in contact. For this reason it should 

 not be used in proximity to painted buildings. 



Miscible or ''soluUe' oils of which there are many brands on 

 the market, are useful and convenient preparations for the control 

 of scale insects. Compared with the lime sulphur-wash, they are 

 less corrosive, not so disagreeable to handle, and may be safely 

 used about buildings. They may be purchased at thirty cents to 

 one dollar per gallon, depending upon the quantity required. They 

 should be diluted with water in the proportion of one to fifteen 

 and should be used only during the dormant season. The con- 

 tainer should be shaken well before drawing off the oil. A few 

 drops of oil in a glass of water should produce a milky solution. 

 If the oil does not mix readily with water as indicated by this test, 

 it should not be used. 



Carbon bisulphide is a heavy volatile liquid and is sometimes 

 used for the control of borers affecting the trunk, and of other 

 insects affecting the roots of trees. It readily evaporates when 

 exposed to the air. The fumes are poisonous and very inflamable. 

 A teaspoonful poured into the burrow of a wood boring insect, and 

 the opening stopped up with wax, will usually kill the pest. The 

 fumes being heavier than air, settle to the lower places and it is 

 well, therefore, to get the chemical into the top of the burrow. If 

 a tree trunk is badly infested it is sometimes advisable to arrange 

 an oil-cloth jacket around the trunk, tying it tightly above and 

 below the affected area. A saturated sponge holding about a cup- 

 ful of the liquid may be hung beneath the jacket and at the upper 

 part of the trunk. The fumes will penetrate into all crevices, and 

 within twenty-four hours the inclosed insects will be suffocated. 



FUNGICIDES 



The use of fungicides is to kill fungus spores and to prevent 

 their access into the tissues of the plant. The standard fungicide 

 is Bordeaux mixture which may be made up as follows : 



