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pests succumb readily to treatments of pyrethrum powder as recommended for the 
celery leaf tier, and arsenical applications are not necessary. 
Cutworms 
The use of a poisoned bait is the only practicable means for the control 
of the majority of the species of cutworms attacking celery. The risk from 
poison residue can be eliminated by distributing one of the standard cutworm 
baits between the rows, provided care is taken to keep the bait from falling 
on the plants. 
In the Florida celery district the southern armyworm is usually consid- 
ered as a cutworm, inasmuch as it exhibits similar habits in the late stages of 
its development. The successful control of this species, however, depends on 
the prompt application of an arsenical at the time the eggs are hatching. Paris 
green added to the regular bordeaux mixture and applied when the presence of the 
young worms is first detected may be used, provided no applications are made on 
plants which will be harvested within a period of less than 6 weeks. From 1 to 
2 pounds of paris green per 100 gallons of bordeaux mixture have been used 
successfully. 
Cultural practice 
Under Florida conditions, the cleaning up of the crop refuse during 
harvest is valuable in pest control, particularly of the celery leaf tier. 
LETTUCE AND SPINACH INSECTS 
There are several leaf-feeding forms which may attack lettuce and spin- 
ach, and on occasion cause considerable damage. Pyrethrum or derris is recom- 
mended as a substitute for the arsenicals in the control of these pests, using 
the same dosages as given for cabbage worms. 
MELON WORM AND PICKLE WORM 
The indications are that the melon worm and the pickle worm may be con- 
trolled satisfactorily on squash in the coastal areas of North Carolina and 
South Carolina, and probably elsewhere when the returns from the crop will 
justify the expense involved, by dusting with a derris-sulphur mixture con- 
taining from 1 to 1.5 percent of rotenone. In instances of light to moderate 
infestation the 1-percent or even 0.5-percent strength rotenone dust should be 
sufficient if it is applied early and regularly. Where the infestation is 
heavy the 1.5-percent dust should be used. While finely ground dusting sulphur 
seems to be the most effective diluent for derris powder for use in melon worm 
and pickle worm control on squash, this material may cause slight injury to the 
foliage of this crop. The addition of from 10 to 25 percent of tobacco dust, 
clay, or talc to the derris-sulphur mixture will improve its dusting qualities. 
The treatments should be begun when the worms first appear on the leaf 
buds of the squash plant, which may be within a week or 10 days after the plants 
appear above ground, and continued at 7-day intervals as long as the worms are 
present or the crop is being harvested. The rate of application will depend 
