Wireworm populations can be estimated by taking square foot soil samples to a depth of
about 2 to 3 inches around mint plants from several different locations in the field.
Usually, wireworm larvae, if present, also will be collected at the same time samples are
taken for redbacked cutworm, strawberry root weevil, mint root borer, and symphylans. Soil
should be screened in the field or placed in Berlese funnels to extract these pests.
No treatment threshold has been developed for wireworms on mint. Wireworms seldom cause
serious damage on established mint, but they may be devastating to new plantings. Damage
may occur if mint is to be planted in fields with a previous history of wireworm injury or
in noncrop or fallow land. Fields that have been fallowed for several years or planted in
potatoes, cereals, grass seed crops, or sugarbeets should be sampled before planting mint.
Using mint roots free of insects to establish new fields is of utmost importance. If mint
is to be planted in fields with a previous history of wireworm injury, growers should
consider fumigating the soil prior to planting mint. Use Telone II or C-17 at the rates
recommended on the label. Fumigation is expensive and therefore usually used to control
multiple pests. Fields with a previous history of wireworms may be fallowed and frequently
cultivated to kill weed hosts for 1 year prior to planting mint, but, since wireworms may
take up to 3 years to complete development, some wireworm larvae may remain in the field
even after 1 year of fallow.