GUIDEBOOK FOR 1939 
Page 33 
CORROSIVE SUBLIMATE 
Also known as mercuric chloride treatment. 
This produces such wonderful results, 
with so little effort, with so little cost, 
that no one, whether he grows a bed of 
glads four foot square or four acres, 
should fail to so treat his bulbs. Re¬ 
gardless of where or how the bulbs grew the 
preceding year. This gives the bulb a coat¬ 
ing that wards off various bulb diseases 
and fungus attacks. We used to keep our 
bulbs healthy by this process long before we 
ever heard of thrips. Now, it has been con¬ 
clusively proved, this treatment also kills any 
thrips and their eggs, and, if used, you only 
need keep a watchful eye for thrips infestation 
from outside sources. Remember soaking pro¬ 
cesses are only advisable just before planting. 
This is not a fall treatment. If your bulbs are 
husked, they need only be soaked half as long, 
but we do not advise husking unless you 
know your bulbs are infested badly and you 
wish to take no chances on penetration to the 
bulb. Many have inquired if the treatment is 
safe to use on badly sprouted or rooted bulbs. 
This will not harm them. 
We read an article in a Canadian “quarter¬ 
ly” by someone who called himself “I Dip- 
pern,” who said he had a lot of little batches. 
To keep them separate he obtained some of 
the women folks’ old stockings, slipped a 
batch into a toe with wooden label, tied the 
stocking above the batch and so proceeded 
until all the batches were conveniently ready 
to soak, remove and drain. 
Note Important Revision of formula by 
U. S. Dept. Ent. to allow additional time for 
penetration of stubbornly tight husks. 
Dissolve 1 oz. of the powder first in a bit of 
hot water, then pour into 7 gal. of water, pre¬ 
ferably above 60 degrees. Remember, cold 
water may render the treatment ineffective. 
This must be poured into a non-metal con¬ 
tainer, such as a crock, wooden pail, glass or 
unchipped granite ware. Varieties kept sep¬ 
arate in cloth bags. No difference if bulbs are 
then planted wet or dry, but the sooner the 
better as much of the coating may be lost if 
bulbs become dry. Solution weakens with 
use, so replenish 100% if used again. Soak 12 
to 17 hours, preferably night before planting. 
Be sure bags are fully immersed. Do not use 
this substance in tablet form unless you learn 
exactly how much of the tablet, in weight, is 
actually corrosive sublimate. You want a 
final solution of about 1-1000. This solution 
is safe to the hands but is a deadly poison and 
must be used and disposed of with extreme 
care. 
Our bulbs get the napthalene treat¬ 
ment a week or two after digging, the 
Ethylene gassing late January and the 
unsold bulbs get the corrosive sublimate 
before planting. Advertising “treated” 
bulbs means little unless you know the 
method used and when last used. 
“In regard to coating metal containers for treating 
bulbs with corrosive sublimate, we would suggest a rubber 
base paint such as is used by mirror manufacturers to 
paint the back of mirrors. Asphalt paint commonly con¬ 
tains sufficient creosote to make injury to the bulbs a 
possibility." 4-12-'37. Sidtiey L. Dryfoos, (Fertilizer 
Expert), Dartmoor Rd , CLaeland Ills., O. 
INSECTICIDES 
If thrips appear on your plants they must 
be controlled before the bud spikes emerge 
from the foliage. Watch for any silvery gray 
streaks on the foliage. If permitted to in¬ 
crease unmolested they will extract juices 
from the buds resulting in a burned appear¬ 
ance, they will eat streaks of color off the 
petals even before they unfold and if they 
unfold at all, the petals may crimp up their 
edges and dry to a dull brown. Even the 
young, lemon colored thrips may do this 
damage to the bud so it is important to kill 
such adult thrips as may arrive before they 
lay eggs, also because the young have the 
bad habit of staying inside the bud and crev¬ 
ices of the plant where they are hard to reach 
with insecticides. The silvery gray (feeding) 
streaks on the foliage, in badly infested cases, 
turn brown, stopping both plant and bulb 
growth. 
In our opinion, thrips come more into the 
open during the hours of 4-6 P.M., so spray¬ 
ing is most effective if done at that time. 
Also, the less heat the safer for the plants 
and evaporation is retarded. If plants are 
thirsty when spray is applied, spraying 
hazards are increased. Plants should be 
well watered but the foliage should be dry 
before the spray is applied. Spraying but 
one part of the patch only is inadvisable on 
account of the migratory habits of the insect. 
Plainly we want an insecticide that will not 
burn the plants and that will act as a “double 
action” insect poison effective on both suck¬ 
ing and leaf eating forms of insects. Rotenone 
in proper concentration, with a spreader 
that will not deteriorate the ingredients, 
is both inexpensive and more effective than 
any other formula that has come to our 
attention. Above all, we beg our readers 
not to put off inspecting the plants for thrips 
infestation until blooms appear. If they 
already have a good foothold at that time 
you may have a very discouraging task on 
your hands. 
We recommend preventive spraying, 
using a somewhat lighter concentration than 
advised for serious infestations. Either about 
once every 10 days after plants are up 6 or 8 
inches until blooming, or else about 4 spray¬ 
ings about 4 days apart beginning about 20 
days before blooming, i.e., about when the 
bud spikes begin to fatten the stalk. If an 
infestation is actually present, use full 
strength concentration. In any event, have 
your insecticide on hand to use if needed. 
