By Mark Shour
Iowa State University
As the calendar page turns to November, a day near the end of the month, Thanksgiving, provides a time to reflect on important relationships, provisions of food, clothing, shelter and for life itself. This holiday also stands out prominently in childhood memories – family gatherings, football games on TV, and a cornucopia of smells emanating from the kitchen. And for a moment, let’s take the entomologist’s point of view: “How do insects impact the feast of Thanksgiving?”
If the menu includes wild turkey or free-range turkey, six-legged animals figure significantly in their growth. The diet of poults (young fowl) consists of 75 to 90 percent protein-rich insects, while adult turkeys consume 75 percent plant material and 25 percent insects. Among the insects eaten are carpenter ants, field crickets, walkingsticks and various grasshoppers, flies, caterpillars and beetles. Turkeys also eat spiders, ticks, centipedes, millipedes, harvestmen and other small animals.
Insects assist us by pollinating some of the common side dishes served at Thanksgiving – carrot, cucumber (pickles), parsnip, pumpkin, squash, rutabaga and turnip – as well as some fruits (apple, blueberry, cherry, cranberry, peach, raspberry and strawberry) used to make pies, jams and relishes. And dressing is incomplete without celery, onions and parsley, crops that are also insect-pollinated.
But the feast is not complete until the honey, honeycomb or spun honey butter is spread on freshly baked rolls or cornbread, compliments of the domesticated honeybee.
To keep a balanced perspective, insects can interfere with or destroy the foods we associate with Thanksgiving. Farmers are owed a note of gratitude for their efforts (crop rotation, new varieties, adjusting planting dates, providing proper cultural care and various other management techniques) to bring to market the wonderful produce we enjoy. Here’s a short list of insect pests and the ‘Thanksgiving’ crops they feed on:
- Apples – apple maggot, borers, coddling moth, European red mite, fall webworm, flower thrips, green apple aphid, green fruitworm, green June beetle, Japanese beetle, leafrollers, Oriental fruit moth, periodical cicada, plum curculio, rosy apple aphid, San Jose scale, spotted tentiform leafminer, stink bugs, tarnished plant bug, two-spotted spider mite, white apple leafhopper, woolly apple aphid
- Carrot and parsnip – aster leafhopper, carrot rust fly, carrot weevil, onion thrips, wireworms, yellow woollybear caterpillar
- Celery and parsley – American serpentine leafminer, beet armyworm, cabbage looper, carrot rust fly, cutworms, green peach aphid, melon aphid, swallowtail caterpillars, two-spotted spider mite, wireworms
- Cranberries – black-headed fireworm, cranberry fruitworm, cranberry girdler, cranberry rootworm, cranberry tipworm, cranberry weevil, false armyworm, humped green fruitworm, spanworms, sparganothis fruitworm
- Green beans – bean leaf beetle, corn earworm, European corn borer, Mexican bean beetle, potato leafhopper, seed corn maggot, stinkbugs, tarnished plant bug, wireworms
- Olives – black olive scale, California red scale, lacebugs, olive fruit fly, olive scale
- Onion – leafminers, lesser bulb fly, onion maggot, onion thrips, wireworms
- Pumpkin and squash pests – aphids, beet armyworm, cabbage looper, cucumber beetle, cutworms, garden fleahopper, melonworm, South American fruit fly, squash bug, squash vine borer
- Sweet corn – corn earworm, corn flea beetle, corn leaf aphid, corn rootworms, cutworms, European corn borer, fall armyworm, Japanese beetle, sap beetles, seed corn maggot, white grubs, wireworms
- Sweet potato and Irish potato – banded cucumber beetle, cabbage looper, Colorado potato beetle, cutworms, elongate flea beetle, European corn borer, green June beetle, green peach aphid, May beetle, palestriped flea beetle, potato aphid, potato leafhopper, potato psyllid, seed corn maggot, spotted cucumber beetle, sweet potato flea beetle, sweet potato weevil, tarnished plant bug, wireworm
- Turkey and chicken – bedbugs, chiggers, house fly, poultry lice, poultry mites
- Turnip and rutabaga – cabbage root maggot
- Wheat – army cutworm, Banks grass mite, bird cherry-oat aphid, cereal leaf beetle, chinch bug, English grain aphid, fall armyworm, false chinch bug, false wireworms, flea beetles, grasshoppers, greenbug, Hessian fly, pale western cutworm, Russian wheat aphid, two-spotted spider mite, wheat curl mite, wheat head armyworm, wheat stem maggot, white grubs, winter grain mite, wireworms