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POTATO INVESTIGATIONS LABORATORY
Mimeo Report 62-3*
October 6, 1961
CONTROL OF INSECTS ATTACKING IRISH POTATOES IN THE HASTINGS AREA
Ralph B. Workman, Assistant Entomologist
FOLIAGE INSECTS: Green peach aphids are the most important foliage insects of
potatoes in the Hastings area. Large numbers of these aphids develop on the lower
leaves of cabbage and migrate to potatoes. Cabbage fields should be well disked
shortly after the last cutting to prevent further movement. Aphid infestations
begin on the lower leaves of potatoes. Insecticide coverage must be thorough for
best control. Check periodically to see where the insecticide is being deposited.
Spreader-stickers are not necessary with good application.
SOIL INSECTS: Trapping of southern potato wireworm adults has continued at the
Potato Laboratory. Numbers from May to November for 1959 and 1960 were 27,254 and
71,448 respectively. Numbers from May to October 6, 1961 were 121,065. High adult
numbers can result in high wireworm numbers under favorable conditions. Little
wireworm damage to potatoes was reported last season. Insecticides for wireworm
control should be applied prior to planting and thoroughly disked into the upper
4-6 inches of soil as soon as possible. Treat when there is good soil moisture as
wireworms move downwards below the treated zone in dry soils.
Table 1.- Insecticides Recommended for Control of Insects Attacking Irish Potatoes
in the Hastings Area.
Insecticide Amount Min. days
Insect (E=Emulsible) per before Notes
Endrin 1.6E 1 pt. 3 Parathion is not effective
Aphids Thiodan 2E 1 qt. NTL1 against green peach aphids.
Endrin 1.6E T1 pt. 3 1 To soil and foliage when
Cutworms Toxaphene 8E 1-2 pt. NTL cutworms appear.
Leaf-footed Endrin 1.6E 1 pt. 3
plant bug, Parathion 4E -1 pt. 5
Stink bug, Thiodan 2E 1 qt. NTL1
Worms Toxaphene 8E 1-2 pt. NTL1
Serpentine Parathion 4E --1 pt. 5
Rarely occur in area.
leafminer Diazinon 250AG 1 pt. 14 Rary o r in
jParathion 4E 2 qt. NTL1
Wireworms i250 2-4L1 Preplanting soil treatment
1Diazinon 250AG 2-4 qt. NTL
INo time limitations.
If other concentrations or formulations of the insecticides above
the amount specified accordingly. Dusts may be substituted for e
at the rate of 20-35 pounds per acre. If control does not appeal
at least three days and check once more before retreating. Som
insecticides are slow acting and all of the chemicals listed ab v
several days as foliage treatments.
*Revision of Mimeo Report 61-2.