POTATO INVESTIGATIONS LABORATORY
Mimeo Report 56-3 September 27, 1955
CONTROL OF INSECT PESTS OF CRUCIFERS AND IRISH POTATOES IN THE HASTINGS AREA
T. Mj Dobrovsky
Insecticides are prisons. Some are more violent than others, but all are
dangerous to human life. Even rotenone,-if introduced directly into the blood
stream is toxic to man. It is necessary, therefore, that people who handle insec-
ticides and the consumers of produce treated with insecticides be properly pro-
tectedl Anyone handling insecticides should follow the safety precautions printed
on the labels of insecticide containers. For the protection of consumers, growers
should observe the recommendations given here regarding last applications prior to
Parathion and TEPP are good insecticides but they are highly dangerous to man
when used carelessly They can, however, be handled safely, as demonstrated by the
thbusands'of people who have applied numerous tons of these poisons without any
accidents. For your own protection, read carefully and observe all safety precau-
tions printed on the labels of parathion and TEPP containers.
Cabbage and Related Crops
The attention of cabbage and cauliflower growers is called to the new regula-
tions in regard to spray residues on vegetables. Growers bf other vegetables are
also cautioned to become familiar with the new regulations. Our recommendations
on dosages, as well as those concerning the last applications of insecticides be-
fore harvest are bated on experiments conducted at Hastings and at other"Florida
Experiment Stations. These recommendations should be followed carefully.
Early control of insect pests of cabbage and related crops is more effective
than control applied after insect infestations have become heavy. That is espec-
ially true of aphids. Even a small aphid infestation in the bud of a-young cabbage
plant may prove serious if neglected: once the leaves begin to "cup", the colony
of aphids may be difficult to reach with contact insecticides. Treat cabbage for
aphid control when few aphids are found, and continue this policy throughout the
The waxy nature of cabbage and cauliflower foliage creates special problems in
the application of sprays. Generally speaking, dusting cabbage for insect control
is more effective than spraying. But spraying can also be highly effective when
properly done. If you spray, use a good wetting agent,* unless the insecticide
concentrate contains an excess of emulsifyer.
Use any good wetting agent and follow manufacturer's instructions onte: the
label for amount to add.
Table 1.- Common Insect Pests of Cabbage and Related Crops in the Hastings Area,
Amount in Last Applica-
Insect Insecticides 100 gals./A or tion Before Remarks
_.___Total dust/A Harvest
Aphids 2 l-rathion dust 20-30 bs Some of he 50 para-
25% parathion 7 days thion concentrates
S emulsion 1 pint have excess emulsifyer
505 parathion and can be used with-
S concentrate 1 /2 pint out any wetting agent.
0% TEPP I or1 day Use a wetting agent.
S____ TEPP dust. .-1 30-35 lbs 1 day Effective when fresh.
Army- 105 toxaphene dust 25-30 lbs.
worms 70% toxaphene 21 days
emulsion 1 pint
Cabbage 10, toxaphene dust 25-30 Ibs,
loopers 705 toxaphene 21 days
emulsion 1 pint
5% DT dust 25-30 lbs.
2l DDT emulsion l quart 21 days .__.___
1._ rtenone d 335 Ibs, For worm control less
55 rtenone 0 than 21 days before
wettable powder 4 pounds cutting,
Cabbage 25% pirathion If a 50- parathion con-
webworm emulsion 1 pint 7 days centiate is used, add'
2% parathion dust 20-25 lbs. pt t./1O0 gals, water,
25, DDT emulsion 1 quart 21 days Use a wetting agent
5,7 DDT dust 25-30 Ibs; __with the spray
Cutworms 10$ toxaphene dust 25-30 1bs. To protect newly trans-
70 toxaphene 21 days planted cabbage, a
emulsion 1 pint toxaphene bait or 10%
ST DT dust 25-30 Ibs, granular toxaphene may
25A DPT emulsion 1 quart 21 days be applied to the tops
_._____ of the rows.
Diamond- 5 DT dust 25-30 bs
back moth 25% DOT emulsion 1 quart 21 days
Imported 105 aphene dust 25- lbs; Late applications of
cabbage D5% DDT dust 25-30 Ibs. 21 days toxaphene may leave
worms 70% t
emulsion 1 pint
25% DT emulsion 1 quart _
1% rdStenone dust I30-35 lbs, For worm control less
5% rotenone 0 than 21 days before
weatable powder 4 pounds cutting
Leaf- 25% p4rathion Not a serious pest in
miners emulsion 1 pint 7 days the Hastings area
2% parathion dust 20-25 ibs. every year.
Mole Aldri4 emulsion Apply to surface of
crickets (2 IbW. actual/gal.) 1 or 1i gals soil 2-3 weeks before
and Heptachlor emulsion planting seedbed in
Wireworms (2 Ibs. actual/gal.) 1 or 1 l gals. field, disk in.
Complete Insect Control Program
Soil Insects.-- Spray soil surface rith aldrin or heptachlor emulsion 2-3
weeks before planting. Use 1 or'li gallons of concentrate, containing 2 lbs, of
technical insecticide per gallon, in 100 gallons of water. Apply 100 gallons of
this spray per acre. Disk after spraying and rebed.
Be sure to lower the nozzles of the spraying machine within'a few inches from
the soil surface. And also, lower the pressure to about 200 lbs, so that the
spray may not blow up in the air but may all be deposited on the soil.
The dosage of li gallons (3 Ibs. actual insecticide per acre) in 100 gallons
of water is recommended only for soils izhich are heavier than sandy.
Spray: Use 1 quart of 25% DDT emulsion and 1 pint of 25% parathion
emulsion (or 1/2 pint of a 50% parathion concentrate) in 100 gallons of water.
Apply 100 gallons of spray per acre every 2 weeks of the spray season,
'Dust: Use a mixture of 5% DDT and e2 parathion dust at the rate of
20-30 Ibs. per acre, Apply every 2 weeKs.
Note: The regular use of DDT throughout the growing season is an insurance
against cutworms at harvest time.
The use of insecticides on potatoes as recommended does not involve
any poison residue problem
Table 2.-- Common Insect Pests of Irish Potatoes in the Hastings Area.
Insect Insecticides 100 gals./A or Remarks
Aphids 25% parathion emulsion 1 pint
2% parathion dust 20-25 lbs,
25% DDT emulsion 1 quart Controls mild infestations.
Cutworms 70a toxaphene emulsion 1 pint Some years, treatments for
109 toxaphene dust 25-30 lbs, cutworms are needed before
25 DDT emulsion 1 quart the regular spray season
5 DIDT dust 2-30lbs. begins.
Leaf-footed 25/ parathion emulsion 1 pint
plant bug, 2 parathion dust 2- bs,
green stink 72 chlordane emulsion 1 pint
Serpentine 25, parathion emulsion 1 pint
leaf-miners 2%3 parathion dust 20-30 Ibs. _
Wireworms Aldrin' emulsion Apply to moist soil 2-3 weeks
(2 lbs. actual/al) 1 or 1 before planting, disk
Heptachlor emulsion promptly and rebed.
1(2 Ibs. actualal.) 1 or 1 gals. ______