Hastings ARC Research Report PR-1975-7
POTATO INSECT CONTROL IN THE HASTINGS AREA
R. B. Workman, Assoc. Entomologist
FOLLOW ALL DIRECTIONS FOR USE AND SAFETY ON THE PESTICIDE LABEL AT ALL TIMES
Insect Insecticide Amount Cutoff Notes
(E=Emulsible) per acre (days)
Azodrin 5E 13 oz. 7 Aphids on potatoes are re-
Aphids Dimethoate 2.67E 1 1/2 pts. None sistant to DDT, Parathion,
Meta-Systox-R 2E 1 1/2 pts. 7 Phosdrin, and Thiodan.
Monitor hE 1 pt. 14
Systox 2E 1 1/2 pts. 21____ _odi
Armyworms, Azodrin 5E 13-26 oz. 7 Spray up to 1 week of dig-
Cutworms, Lannate,Nudrin90S 1/2-1 lb. 14 going for cutworm; i tuber
Tuberworm, Monitor hE 1-1 1/2 pts. 14 worms. Hillin f er ro-
Other Worms Parathion 8E 1/2 pt. 5 tects tubs nse ts
Phosdrin 2E 1 pt. 1 and gr
Thiodan 2E 1-2 qts. None
Leaf-footed Guthion 2E 1 qt. 7 ,Jkr ffectiv\ tube
Plant Bug. Parathion 8E 1/2 pt. 5'. A
Green Phosdrin 2E 1 pt. 1
Stinkbug Thiodan 2E 1-2 qts. None -
Wireworm Diazinon 4E 1-2 qts. None Prdplant soil t "Ot .
Parathion 8E 1 qt. None See 'Wirewormsal'w.
Leafminer May be numerous at harvest but rarely cause damag.'
*Adjust dosage for other formulations.
APHIDS: Aphids start on the underside of the lower leaves netto the soil sur-
face. Under certain conditions, they multiply until hundreds occur on all leave
to the top of the plant. To control aphids, apply a systemic insecticide when
the plants are 12-16 in. high and beginning to bush out. Systemic insecticides
allow aphid parasites and predators to build up, however, they are less effective
on older plants. Drop nozzles and a spray pressure of 200-300 psi will give the
best coverage. Aphids cannot be reduced under about 1-2 per leaf. Watch the
plants and if aphids are becoming numerous and moving up on the vines another
treatment is needed. Strong vigorous growing plants can withstand fairly large
numbers of aphids. The large aphid populations of some years ago which killed
untreated potato vines have not occurred during the past few seasons.
CUTWORMS: Cutworm eggs are laid on and around the lower part of the potato plant
The worms hide in the soil, feeding first on the leaves, later on the tubers.
Most cutworm damage occurs to tubers close to the soil surface or those exposed
by cracks or washing rains. Keeping tubers covered with soil will reduce most
damage from cutworms and tuberworms.
TUBERWORMS: Tuberworms are most abundant during hot-dry seasons. They attack t.
tubers through cracks in the soil. Potatoes stored during the summer should be
screened to prevent tuberworm buildup and carryover to the next season.
WIREWORMS: Little damage from wireworms has been found on potatoes the past
TUBER DAMAGE: Nearly all nondisease injury to potatoes at the graders last seas
was caused by greening, from light exposure, and cutworms. Much of the cutworm
damage was on greened tubers.
AGRICULTURAL RESEARCH CENTER