1934 BRIEFS ON THRIPS 
Thrips Can Be Controlled and Eliminated: This is Past History. 
Read on another page what a noted investigator said about our article in last season’s 
Catalog, “Co-operation vs. Thrips Control”. We were flooded with letters of approval. 
We can still supply this article on request. 
Nearly all growers who have had several years experience have eliminated thrips. 
The best method for the amateur and small grower is naphthalene. After you dig your 
bulbs, let them dry a few weeks, then remove roots and put the bulbs in bags, and after 
adding 1 ounce or more of naphthalene to each 100 bulbs, tie bag and put in a room 60 F. 
or above for three weeks. Then remove from bags and place bulbs in shallow boxes or 
trays and place in a cool, well ventilated storage. If you can maintain temperature below 
50 F. it will be more desirable as thrips do not increase in storage that is held below 50 F. 
About three weeks before you are ready to plant, give bulbs a second naphthalene treat¬ 
ment. If you have larger lots, and wish to leave them in trays, you can add the naphtha¬ 
lene, then cover boxes tightly with heavy paper and stack in a solid pile. The main 
object is to confine the fumes; if you have a small, tight room or even a very large, tight 
dry goods box on which you can place a tight cover, you will then have an ideal “fumi- 
gator” in which to stack your boxes and trays of bulbs. One man used an old trunk. 
Because your plants seemed entirely free of thrips the past season is no reason to relax 
your vigilance. Remember a very few insects as a rule are never even discovered, as it is 
only when conditions are favorable and they increase in large numbers that damage is 
noticeable. 
Naphthalene Flakes (or crude) will keep your bulbs 100% free of thrips in any 
storage. We have proven this in our investigations. 
OUTSIDE INFESTATION: This is an ever present hazard, as it is my belief that in 
nearly all cases where the insect is still troublesome in sections where the ground freezes 
it is caused by people who do not know about the PROVEN METHODS OF PREVEN¬ 
TION as many other commercial bulb Growers as well as myself have pointed out in the 
past two seasons. Just a few days ago our State Nursery inspector said to me that practi¬ 
cally all persons who grew glads around the city of D- had thrips the past summer 
except Mr. S-, and Mr. S. bought all his bulbs from us, and used the naphthalene 
treatment as we advised him. In 1932 I remember that one man had a planting of glads 
that became infested by migratory insects. They appeared late in August, and in such 
large numbers on the outside leaves of the plants that you could count fifty or more adults 
on many single plants. What do you think was the cause of this heavy migration? 
About 400 feet away Was a residence and small garden in which grew a very few plants, 
I do not think over 200 or 300 mixed varieties. These were untreated stock and were 
heavily infested. After they had destroyed the host plants they migrated to the larger 
planting nearby. 
There are millions of persons who grow a few glads in an indifferent manner. In 
most cases they do not come in contact with any publication or information about thrips 
control or elimination and not knowing the cause of their loss, ascribe it to various other 
causes and go on replanting, storing and increasing thrips. As far as the INFORMED 
public is concerned, you need have no worry at all concerning thrips control. It is an as¬ 
sured and proven fact. 
Thrips made their first destructive appearance in the year 1930, causing damage in 
Eastern Canada and Ohio, and they have now spread to every state in the Union. They 
were very severe last season on the Pacific Coast. I have letters in my file that show 
the damage to have been as high as a 75% loss of the entire cut flower crop. Do not be 
misled by false advertising from any section claiming entire freedom from thrips damage. 
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