Agronomic Crops

Sugarcane
Beetles
Sugarcane beetle adults may enter fields from root enlargement until harvest. e beetles burrow down to the roots
and feed. Currently no effective insecticides have been identified for controlling sugarcane beetles in sweetpotatoes. In
fields that historically have had sugarcane beetle problems, crop rotation may be beneficial. Sweetpotato fields near pastures
or hay fields appear to be more at risk for sugarcane beetle infestations. Planting more productive fields (fields
with higher yield potential) first and harvesting them as soon as possible may allow these fields to be harvested before
sugarcane beetle infestations get severe. Sugarcane beetles may also be brought into storage facilities on or in infested
potatoes. Sugarcane beetles are strongly attracted to lights. In storage areas kept in darkness for periods of time (such as
overnight), light traps may be helpful in capturing beetles and reducing damage to stored sweetpotatoes.
Thrips
Insecticide
Amount of
Formulation per Acre
Pounds Active
Ingredient per Acre
Acres 1 Gallon or
1 Pound Dry Will Treat
PHI
(days)
Comments
soil Application:
imidacloprid (N)
Admire Pro 4.6 SC
7–10.5 oz.
0.25–0.38
18.3–12.2
125
Foliar Application:
λ–cyhalothrin (P)
Karate Z 2.08 CS
1.28–1.92 oz.
0.02–0.03
100–66.7
7
Does not control western flower thrips.
spinetoram (SPN)
Radiant 1SC
6–8 oz.
0.05–0.06
21.3–16
7
spinosad (SPN)
Blackhawk
2.25–3.5 oz.
0.05–0.08
7.1–4.6
3
tHRIPs can stunt and reduce growth in young transplants. ey can quickly infest freshly planted fields, especially when alternate
hosts (weeds and border plants) are senescing or have been destroyed by chemical or mechanical means. Scout for thrips by
beating plants onto a white surface and counting them as they move about. Sample at least 50 plants.
tHResHoLD: Treat when plants are stunted and thrips are present.
Storage
Insects
Insecticide
sweetpotato Weevils
phosmet (OP)
Imidan 5D
4 oz./50 bu
Amount of Formulation per Acre
Threshold and Comments
Apply to stored Sweetpotatoes in areas of suspected sweetpotato weevil infestation
as a preventive treatment.
Fruit Flies
pyrethrins
Apply 1 gal. of solution/100,000 cu ft. Refer to label for proper
dilution.
Space spray for stored sweetpotatoes.
sugarcane Beetles
Supplemental Information
Sugarcane beetles may also be brought into storage facilities on or in infested potatoes.
Currently no effective insecticides have been identified for controlling sugarcane
beetles in sweetpotatoes. Sugarcane beetles are strongly attracted to lights. In
storage areas kept in darkness for periods of time (such as overnight), light traps
may be helpful in capturing beetles and reducing damage to stored sweetpotatoes.
Based on historical data, the following pests could be expected at different stages of plant development. is is a generalized
statement; conditions may be different on specific farms or in specific seasons.
stages of Plant Development
Plant beds
Planting to runner development
Canopy closure to full root development
Root maturity to harvest
Post-harvest storage
Insect Pests
Sweetpotato weevils, flea beetles, aphids, whiteflies
Wireworms, white grubs, root worms, flea beetle adults and larvae, whitefringed beetle
larvae, cutworms, thrips
Wireworms, root worms, white grubs, flea beetle larvae, caterpillars
Wireworms, root worms, white grubs, flea beetle larvae, sugarcane beetles, caterpillars
Sweetpotato weevils, sugarcane beetles, fruit flies
Foliar Insecticide Application Recommendations
Adequate coverage can be difficult but is essential with most products. Best results from contact insecticides will be with application
volumes of 5 to 10 gallons per acre. Apply foliar insecticides with hollow cone nozzles and do not exceed 12 gallons per acre
application volume.
80 Sweetpotatoes