Rules, Notes and Recipes 
201 
Shading, Wash for. — A very good wash may be made as follows. 
Ingredients: 1 lb. of wheat flour, % lb. of whiting, and l lb. of common 
candle or tallow. Make the flour into a paste and then put in the 
candles while the paste is hot; crush the whiting into a powder, mix 
with cold water, and then add to the paste, also adding as much 
Brunswick green as required. When required for use warm it in a 
pail and paint the glass when the sun is shining upon it. In many 
cases, however, lime-wash by itself is simply sprayed upon the roof 
glass of greenhouses, and if some salt is added it sticks better. 
Sings and Snails. — To get rid of these pests, so destructive to 
young plants and seedlings in greenhouses and in the open air, the soil 
may be dusted with slaked lime, or soot, or with the proprietary 
preparation called “Slugicide,” an English compound. There is also 
the V. T. H. patent slug trap, by which the slugs, also sow- 
bugs, weevils, wireworms, and leather-jackets are attracted and fall 
into salt and water. More than 200 slugs and many more sowbugs have 
been caught by this trap in a single night. Salt is sometimes recom- 
mended as good where it can be used without injury to the plants 
or crop. Moistened bran in which some sugar and Paris green have 
been mixed, placed alongside the plants, may destroy some snails. Other- 
wise, place pieces of boards of convenient size flat on the soil. Under 
these the snails and slugs collect and can be gathered each morning and 
destroyed. A speedy and sure way to get rid of these pests is to hunt 
for them in the evening, with a light, or during showery weather, and 
if stabbed in the shield portion behind the head they die at once. 
Soil Sterilization. — Within th<* last few years we have heard 
much of the artificial sterilization of soils, and had it advocated as a 
desirable factor in horticulture or of plant cultivation under glass. The 
term is a bad one: what is inferred is partial sterilization, and the prac- 
tice of partially sterilizing one’s soil depends upon the fact that the 
soil contains certain forms of protozoa that are inimical to the nitri- 
fying bacteria, and that while the bacteria pass a portion of their life 
in the state of spores, the inimical forms have no such resting period. 
They are, therefore, vulnerable all the time and are killed off by the 
sterilization processes more rapidly and in larger numbers than the 
bacteria that are beneficial. The latter, therefore, quickly multiply 
again, and this multiplication results in an Increase of the available 
nitrate supply, which tells its tale in the quicker, larger growth of the 
crops. Sterilization is performed best of all by heating the soil. Ex- 
treme dryness, continued for some little time, will cause sterilization. 
But in large establishments sterilization is performed by steam pres- 
sure. The soil is filled into a vat, or bin, or box, with a lid, and com- 
prising, say, 70 up to 260 cu. ft., with 2in. piping underneath, such 
piping being perforated every Sin. or 4in. apart, through which the 
steam from a boiler is forced. The pressure maintained is just suf- 
ficient to cause the whole mass of soil to become heated to about 205 
deg. F. and is maintained for 25 minutes at a pressure of 20 lbs. 
