GELSER BROTHERS — DALTON, NEW YORK 
GLADIOLUS THRIP 
The Thrip is a very small insect about 1/20 of 
an inch in length and not easily seen, except when 
numerous. Thrips do not overwinter outdoors, 
where the ground freezes. The main source of in- 
fection is from planting bulbs infected with the 
insects. If your gladiolus did not blossom as well 
as in former years, it may have been due to the 
Thrip and you should treat your bulbs before 
planting. 
For treating a small number of bulbs, the sim- 
plest and most convenient method is by the use of 
NAPTHALENE FLAKES. This material is inter- 
mixed with the bulbs at the rate of 1 oz. to 100 
large bulbs, in a paper bag or box gives complete 
control. After 2 or 3 weeks all insects should be 
dead. Do not delay this treatment too long, as the 
small root-nobs that form toward spring may be 
injured by the napthalene. Also remove the nap- 
thalene from the bulbs after treating. 
Bichloride of Mercury will give good results in 
the control of Thrips. Use one ounce to seven gal- 
lons of water and leave in the solution over night, 
twelve hours or more at a temperature of 70 de- 
grees or warmer. You must use a non-metal con- 
tainer, as a crock, glass or wooden pail. Varieties 
can be kept separate in cloth bags. This solution 
is a deadly poison and must be used and disposed 
of with extreme care. 
Napthalene and Bichloride of Mercury may not 
be available for the duration. In that case you 
can use LYSOL, which you can purchase at any 
drug store. Use 4 teaspoonfuls of Lysol to one 
gallon of water and leave bulbs in this solution 
for 6 or 7 hours. 
The Bichloride of Mercury and Lysol treatments 
should be used just before planting. 
Tartar Emetic Spray for Gladiolus Thrips. 
Tartar Emetic can be purchased from almost 
any drug store. Use one ounce of Tartar Emetic 
and four ounces of brown sugar to three gallons 
of water. Spraying should be started as soon as 
the plants are 6 inches high and continued until 
buds show color. 
The plants should be sprayed every 10 days and 
after every hard rain when the foliage is dry. A 
very fine mist is most effective. 
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