DAHLIADEL NURSERIES 
CULTIVATION 
By cultivating at least once a week, twice preferably 
in the early season, and as soon after rain or irrigating 
as the ground can be worked, the weeds will be held 
in check and a soil mulch formed which will conserve 
the moisture and lessen the need of irrigafion. 
As the plant develops and the feed roots come 
toward the surface, the ground should be worked 
rather shallow around the hill for the radius of at 
least a foot. Still work the balance of the ground 
rather deep and bring some fresh soil to the plant at 
each cultivation, giving the plant a new supply of food 
and protecting the surface roofs from the heat of the 
sun. Have the hills mounded 3 to 5 inches by the 
middle of September. This will help support the stalks 
and protect the roots from freezing should an unex¬ 
pected cold spell catch you before digging. 
PESTS 
THRIPS are tiny insects which in the nymph stage 
are less than i/g of an inch long and a greenish gray 
color. They enter the growing leaf bud and chafe the 
newly formed leaves, injuring them so that they de¬ 
velop malformed and curled, also injuring the small 
flower buds and stems. These insects seem to enjoy 
the life blood of certain varieties on account of its 
flavor and do not molest the adjacent bush. If the 
attack is not checked the leaves will be gnarled and 
twisted, the buds one-sided or so injured that they dry 
up and fall off. This usually results in a stunted bush, 
which in reality is only debilitated by insect ravages. 
LEAF-HOPPERS are larger than thrips and of a 
pale yellowish green color, a little over l/g Of an inch 
in length. They fly when the bush is touched during 
the heat of the day. These sucking insects do much to 
keep a plant from getting a good start. 
APHIDS (plant lice) are soft-bodied, sucking in¬ 
sects which usually work on the under side of the 
leaves in groups, causing the leaves to curl. Thrips, 
leaf-hoppers and aphids are possible common carriers 
of virus diseases and should be kept in control for this 
reason, if for no other. 
A good control method is to spray with pyrethrum 
soap. This can be done at any time of day and re¬ 
gardless of weather conditions, except rain. We have 
found this very effective for leaf-hoppers, thrips, red 
spiders and aphids. Use 4 ounces to 5 gallons of water. 
For all beetles, grasshoppers, ants and more hardy 
insects, use double strength or half the amount of 
water. Should a bush be infested with ants, spray 
bush and pour a few quarts of spray down the ant 
hill, or enough to fill the hill. This will do the dahlia 
no harm, but kill the ants. A number of our customers, 
as well as ourselves, have had wonderful results by 
using a pyrethrum soap, 4 ounces to 5 gallons, and 
adding I l/j teaspoonfuls of Black Leaf 40 to each 
gallon. This kills not only by asphyxiation, but also by 
the toxic action of the pyrethrum. 
Another control of thrips, leaf-hoppers and aphids 
is dusting with a good nicotine dust. Apply in sunshine 
with the temperature above 70 degrees at weekly in¬ 
tervals as a preventative from the time the plants are 
set or roots start to grow, and if any should appear 
then about every four days until they are controlled. 
For small plants a paper funnel on the end of the 
duster spout, held over the plant for about one minute 
when dusting, will increase the kill materially. 
During the windy weather when dust cannot be 
applied to advantage, overhead sprinklers used during 
the heat of the day will control red spider and check 
the leaf-hoppers and thrips. See "Irrigation." 
By dusting or spraying before the presence of in¬ 
sects, it is doubtful if you will see any. As it is difficult 
to procure nicotine dust and pyrethrum soap in most 
localities, we are listing them under "Dahlia Growers' 
Supplies." 
RED SPIDER in late years has caused considerable 
damage to dahlias. This insect is barely discernible 
with the naked eye and works with such rapidity that 
you may have a row of dahlias today and within a few 
days or a week all the lower leaves will be as brown as 
cured tobacco leaves. There will be a very fine white 
web in evidence on the under side of the leaf. These 
insects multiply very fast in dry, hot weather, do not 
like strong air currents, and cannot stand cold water, 
especially applied with pressure. Syringing or spray¬ 
ing will help in their control. A spray of one level 
teaspoon of Colloidal Sulphur to one quart of water 
will be found very effective, and two sprays two or 
three days apart should clean up the infestation 
entirely. 
CUT WORMS are easily controlled by scattering 
about a teaspoonful of poison bran bait around the 
plant (but not touching it) as soon as plants are set 
or shoots appear from roots. The early evening is the 
best time to apply it. 
2 tablespoonfuls of molasses or brown sugar (dis¬ 
solved ). 
I level teaspoonful paris green mixed in. 
Juice of an orange or equivalent in water. 
I quart of bran or enough to make a reasonably dry 
mash. 
STEM BORER. This black-and-white-striped worm 
when small enters the stem just above the ground and 
usually works upward. It will be noticed in the early 
season by the shortening of the internodes and later 
on by wilting. When noticed early, cut the plant off 
near the ground and get the borer with your knife. 
If the borer is below where you want to cut back, use 
a hooked wire from the top. A plant cut back not 
later than July 15th should be in full bloom early in 
September. Wax or plaster paris may be used to 
close up top of plant after borer is out so water will 
not get in and rot the plant. 
Should a plant be too large to cut back when borer 
is discovered, use pyrethrum soap at strength of 2^2 
ounces to gallon and inject with ear syringe. This will 
kill the borer or drive it out. Drain stalk out by slitting 
at the bottom to prevent stem rot. 
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