· 22 Bulletin N0. 147., - -
l T ever, destroy the adults of all hothouse pests, and has no effect I D 3
  at all on the scale insects nor on the immature White fly.   V ` ‘ C
T For the more hardy plants the following dose has been _ E
, used, though with a little injury to some of them. For each - l
T 1000 cubic feet enclosed: _   T
. j 0.50 ounce cyanide of potassium · ]
0.60 fluid ounce sulphuric lacid. o ; -
` 1.50 fluid ounce water A ‘  
` Start at eight o’clock in the evening and leave until ten- ` I
thirty, then air out. q »_ J
For more tender plants, and for use against the adult
white fly and the wheat and lettuce aphis: ` »
` 0.25 ounce cyanide of potassium ;
. 0.30 ounce commercial sulphuric acid ·
0.75 ounce water ·
1 Start at eight o’clock p. m. and leave all night. 0 T
Insects are sometimes less dimcult to suppress than the h
more or less invisible plant parasites, causing the various  
blights, mildews, rots and scabs. As a rule, too, fungi must Q
be fought with other remedies, and these are not yet in all '
_ cases as satisfactory as could be wished. Some of the in-, j
secticides serve also as fungicides, and where they do not j
the two can often be combined in one preparation which will
serve for both. The lime—sulphur wash is one of the best of l
‘ those which serve to check both insect and fungus pests. ’ ·
Bordeaux mixture is not so good an insecticide, though when  
used in midsummer on foliage it often prevents much of the ; l
injury from gnawing insects. By adding arsenate of lead to b
it we get one of the very best insecticide-fungicide sprays _ _
yet devised. ,  
This is the active and most essential ingredient of Bor- .
deaux mixture. Concentrated solutions of it cannot be used .