Page 6 
THE GLADIOLUS FANCIER’S GUIDEBOOK FOR 1934 
INSECT PESTS AND BULB DISEASES 
This subject, fortunately, has again be¬ 
come relatively unimportant to the well in¬ 
formed, who have learned that simple, 
preventative measures are better than com¬ 
plicated and sometimes ineffective curative 
measures. 
Likely, your bulbs are clean and need 
none of these treatments, but we are present¬ 
ing this information for those who may need 
it. 
Inspect your bulbs before planting. If 
doubtful looking, remove entire husk, 
though the husk does function to ward off 
from the planted bulb frost, fungus diseases, 
grubs and wire worms. A few specks of 
disease spots, wire worm injury or scab may 
be gouged out without the slightest harm to 
the plant provided the bulb retains a good 
eye and root base. Cutting out these seg¬ 
ments only cuts away that much food to 
start off the new plant. Best dust the cut 
surface with powdered charcoal. Next best 
common sulphur or at least dry until bleed¬ 
ing stops before planting. You may do these 
things any time during the storage period, 
too. 
A plump bulb of 1)4 inches diameter has 
plenty food to start production of a show 
specimen spike. If the bulb is 2 inches or 
more in diameter it may have two or more 
prominent eyes or sprouts, indicating that 
it will make as many stalks and spikes. Now 
this one bulb cannot be expected to make two 
or more spikes of the same show specimen 
quality it would produce if held to a single 
eye and spike. If you want to bring renewed 
youth and vigor to your bulbs and beat the 
other fellow, just disbud the bulb, i.e., gouge 
out all eyes except the most prominent one, 
just as you gouged out the little specks of 
scab or disease, dusting as before. 
In the hot, dry season of 1930, rather 
generally across the northern and eastern 
states and southern Canada, a small thrips 
insect which had theretofore been too few in 
number to cause enough damage to blooms to 
warrant active steps towards their elimina¬ 
tion, multiplied greatly, as did most other 
insects. 
Many growers, unaware even of the nature 
of the damage to their blooms, attributed it 
to the dry soil and wilting heat and care¬ 
lessly left the foliage on their bulbs when 
dug and otherwise allowed the thrips to fly, 
blow, crawl or shake onto the bulbs, bring¬ 
ing them into storage where they proceeded 
to feed on the bulbs, leaving russett brown 
spots wherever they were able to penetrate 
and laying eggs right in the tissue of the 
bulbs. There the eggs hatch and start 
further life cycles if the place of storage is 
above 50 degrees or, if under 50, remain un¬ 
hatched until perhaps the heat of June or 
July reaches down to the planted bulb. If 
infested thus the young remain inside the 
crevices of the plant, substantially out of 
reach of insect sprays. 
Unfortunately, the first light infestation 
from without usually comes late in the 
season, perhaps not even injuring the latest 
blooms and escapes notice. By getting a 
few introduced into your storage and then 
not using any control methods, you face a 
possible total loss of the next year’s bloom. 
Some growers took measures to kill the 
insects which got into their bulbs in storage 
but failed to kill the eggs and unwittingly 
helped disseminate them about the country. 
Your neighbor may get some of these 
bulbs and spread his crop of thrips over 
your lot. For your own protection, tell him 
how to rid his bulbs of the pesky thrips or, 
better still, give us his name and address and 
we will inform him. 
For several years we have been among the 
foremost disseminators of information re¬ 
lating to this subject in numerous publi¬ 
cations in U. S. and Canada, firm in the 
belief that — the sooner discussed, the 
sooner eliminated. 
Probably a hard winter without too much 
snow, will again make the gladiolus the only 
“fool proof’’flower to grow. Meanwhile, if 
any glad thrips have reached your locality, 
you need only give your glad bulbs and 
plants their share of the attention you have 
always been devoting to spraying your 
roses, dahlias, asters and vegetables and to 
caring for the wintering of tubers, shrubs 
and tender perennials. 
There are many kinds of thrips. We have 
always had thrips of one sort or another on 
corn husks, grapes, oats, onions, lilies, 
peonies, iris, field daisies and the like. 
Some of them do occasional consequential 
damage to the plant giving them their 
common name (“oat thrips,” etc.) Others 
may feed upon pollen only and never do 
noticeable damage. A few thrips other than 
the so called “glad thrips” may migrate 
upon your gladiolus with little or no 
damage. 
The male “glad thrips” is about l-16th 
inch long, female both larger and longer. 
Male has five cream colored bands around 
its body, the female a broader band above 
but none below. End of body of male is 
rounded, that of female a rather pointed, 
saw-like appendage. Main body color of 
both a black brown. Four stages, adult, 
egg, larva, pupa. The young are without 
wings, considerably smaller and lemon 
yellow. A generation develops in about 20 
days at 70 degrees and in but 12 days at 80 
degrees. Since they secrete themselves in 
the leaf sheath, one has to examine his 
plants very carefully or a severe infestation 
may come upon them before he is aware. 
The U. S. Department Entomology is 
profoundly of the belief that, in northern 
