PROTECTING PLANTS FROM THINGS THAT PREY ON THEM - Continued
Always be ready to resort to hand-picking. We have grown so accustomed
to killing insects by other means that we have almost forgotten that
hand-picking is often the surest and sometimes even the most expeditious
means of checking an invasion in a home garden. Many insects can be
jarred off early in the morning. Egg-masses on leaves and stems may be
removed. Cutworms may be dug out. Diseased leaves may be picked off and
burned; this will do much to combat the hollyhock rust, aster rust, and
other infections.
[Illustration: Fig. 220 A compressed-air hand pump for garden work.]
[Illustration: Fig. 221 A bucket pump.]
[Illustration: Fig. 222 A bucket pump.]
[Illustration: Fig. 223 A cart-mounted pump.]
Keep close watch on the plants, and be prepared to strike quickly. It
should be a matter of pride to a gardener to have in his workhouse a
supply of the common insecticides and fungicides (Paris green or
arsenate of lead, some of the tobacco preparations, white hellebore,
whale-oil soap, bordeaux mixture, flowers of sulfur, carbonate of Copper
for solution in ammonia), and also a good hand syringe (Fig. 218), a
knapsack pump (Figs. 219, 220), a bucket pump (Figs. 221, 222), a hand
bellows or powder gun, perhaps a barrow outfit (Figs. 223, 224, 225),
and if the plantation is large enough, some kind of a force pump (Figs.
226, 227, 228). If one is always ready, there is little danger from any
insect or disease that is controllable by spraying.
[Illustration: Fig. 224. A garden outfit.]
[Illustration: Fig. 225. A cart-mounted barrel pump.]
[Illustration: Fig. 226. A barrel hand pump.]
[Illustration: Fig. 227. A barrel outfit, showing nozzles on extension
rods for trees.]
[Illustration: Fig. 228. A truck-mounted barrel hand spray Pump.]
Screens and covers.
[Illustration: Fig. 229. Wire-covered box for protecting plants from
insects.]
There are various ways of keeping insects away from plants. One of the
best is to cover the plants with fine mosquito-netting or to grow them
in hand-frames, or to use a wire-covered box like that shown in Fig.
229. In growing plants under such covers, care must be taken that the
plants are not kept too close or confined; and in cases in which the
insects hibernate in the soil, these boxes, by keeping the soil warm,
may cause the insects to hatch all the sooner. In most cases, however,
these covers are very efficient, especially for keeping the striped bugs
off young plants of melons and cucumbers.
[Illustration: Fig. 230 Protecting from cut-worms.]
Cut-worms may be kept away from plants by placing sheets of tin or of
heavy glazed paper about the stem of the plant, as shown in Fig. 230.
Climbing cut-worms are kept off young trees by the means shown in Fig.
231. Or a roll of cotton may be placed about the trunk of the tree, a
string being tied on the lower edge of the roll and the upper edge of
the cotton turned down like the top of a boot; the insects cannot crawl
over this obstruction (p. 203).
The maggots that attack the roots of cabbages and cauliflowers may be
kept from the plant by pieces of tarred paper, which are placed close
about the stem upon the surface of the ground. Fig. 232 illustrates a
hexagon of paper, and also shows a tool used for cutting it. This means
of preventing the attacks of the cabbage maggot is described in detail
by the late Professor Goff (for another method of controlling cabbage
maggot see p. 201):--
[Illustration: Fig. 231 Protecting trees from cut-worms.]
"The cards are cut in a hexagonal form, in order better to economize the
material, and a thinner grade of tarred paper than the ordinary roofing
felt is used, as it is not only cheaper, but being more flexible, the
cards made from it are more readily placed about the plant without being
torn. The blade of the tool, which should be made by an expert
blacksmith, is formed from a band of steel, bent in the form of a half
hexagon, and then taking an acute angle, reaches nearly to the center,
as shown in Fig. 232. The part making the star-shaped cut is formed from
a separate piece of steel, so attached to the handle as to make a close
joint with the blade. The latter is beveled from the outside all round,
so that by removing the part making the star-shaped cut, the edge may be
ground on a grindstone. It is important that the angles in the blade be
made perfect, and that its outline represents an exact half hexagon. To
use the tool, place the tarred paper on the end of a section of a log or
piece of timber and first cut the lower edge into notches, as indicated
at a, Fig. 232, using only one angle of the tool. Then commence at the
left side and place the blade as indicated by the dotted lines, and
strike at the end of the handle with a light mallet, and a complete card
is made. Continue in this manner across the paper. The first cut of
every alternate course will make an imperfect card, and the last cut in
any course may be imperfect, but the other cuts will make perfect cards
if the tool is correctly made, and properly used. The cards should be
placed about the plants at the time of transplanting. To place the card,
bend it slightly to open the slit, then slip it on to the center, the
stem entering the slit, after which spread the card out flat, and press
the points formed by the star-shaped cut snugly around the stem."
[Illustration: Fig. 232 Showing how paper is cut for protecting cabbages
from maggots. The Goff device.]
Fumigating.
An effective means of destroying insects in glass houses is by
fumigating with various kinds of smoke or vapors. The best
material to use for general purposes is some form of tobacco
or tobacco compounds. The old method of fumigating with
tobacco is to burn slowly slightly dampened tobacco stems in a
kettle or scuttle, allowing the house to be filled with the pungent
smoke. Lately, however, fluid extracts and other preparations
of tobacco have been brought into use, and these are so effective
that the tobacco-stem method is becoming obsolete. The use
of hydrocyanic acid gas in greenhouses is now coming to be
common, for plant-lice, white-fly, and other insects. It is also
used to fumigate nursery stock for San José scale, and mills
and dwellings for such pests and vermin as become established
in them. The following directions are from Cornell Bulletin
252 (from which the formulas in the succeeding pages, and
most of the advice, are also taken):--
"No general formula can be given for fumigating the different
kinds of plants grown in greenhouses, as the species and varieties
differ greatly in their ability to withstand the effects of the gas.
Ferns and roses are very susceptible to injury, and fumigation
if attempted at all should be performed with great caution.
Fumigation will not kill insect eggs and thus must be repeated
when the new brood appears. Fumigate only at night when
there is no wind. Have the house as dry as possible and the
temperature as near 60° as practicable.
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