Hi jane,
Found the following for you. Hope it helps a little !
;) :)
To control wireworms, remove previous crop residue to reduce alternative food sources for larvae. Because wireworms are attracted to grass cover crops, delay cover-crop planting until fall, and leave fields intended for sweet potatoes fallow in the summer. Control weeds adjacent to and within the field before and after planting. Deep plowing will also kill wireworm larvae. Because wireworms are inactive in the spring, plant fields as early as possible. As recommended for whitefringed beetle, harvest sweet potatoes as early as possible because the potential for damage increases with time.
Evaluating new fields for the potential for wireworm problems is difficult, but you should check for wireworms when plowing and discing, and you can set wireworm bait stations in the fall or spring when soil temperatures are above 45 degrees F. Soil-sampling using a 6-inch post-hole digger gives a more accurate estimate than baiting, but it is labor intensive. Use the following procedure to make and set wireworm baits.
Mix a 1:1 combination of wheat:corn or wheat:oatmeal as bait.
Wrap a fist-sized amount of bait in a nylon stocking.
Bury the wrapped bait 4 to 6 inches deep, placing it in random locations in the field to obtain representative samples. Place more bait stations in suspected trouble spots, such as next to weedy or low areas. Use at least one bait per acre--the more stations, the better.
Mound the soil above the bait, and cover it with clear plastic if the soil is cool.
Mark the locations of the bait stations with flags.
Wait 7 to 10 days, and then dig up the bait stations and check for wireworms. Very loose treatment thresholds that have been developed for potatoes are as follows:
0 wireworms/bait = no control needed
0.5 to 2.0 wireworms = moderate chance of damage
3 to 4 wireworms = high chance of damage
5 or more wireworms = do not plant
If observations of wireworms in the field indicate that chemical treatment is warranted, broadcast soil insecticide applications are more effective than banded applications. See the table at the end of this publication for recommended soil insecticides. Soil fumigation will also kill wireworms if they are in the treated soil profile, but wireworms can burrow in the soil below the chemical residue.
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