News Flash

Insects are often considered “pests” but not all bugs are bad. Out of nearly one million known insect species, only about one to three percent are really pests. What about the rest of them? Some insects actually help us by keeping pests in check. 

If we let them do their jobs, many types of insects, spiders, and other creepy crawlies actually help us out. 

• By preying on “pest” insects. Spiders and some types of beetles, flies, true bugs, and lacewings are predators of insects. Ladybugs can eat more than 5,000 aphids and other soft-bodied pests during their one-year lifetime. 
• By parasitizing pest insects. Parasitic insects, like some small wasps, lay their eggs inside insects or their eggs, thereby killing them. This can help drive the pest population down. 
• By pollinating plants. Insects such as native bees, honey bees, butterflies, and moths provide this service, helping plants bear fruit. 
• By acting as decomposers. Insects and other decomposers help break down dead animals and plants in our environment. 
• Don't forget about animals that depend on ‘bugs’ for food! Insects and other invertebrates are underappreciated for their role as a base in the food web. Birds, bats, amphibians, fish, and other animals depend on these organisms as a food source and they themselves often reduce the number of ‘pests’. For example, in one season, an opossum can eat about 5,000 ticks just by grooming. Meanwhile, bird populations are declining around the world, perhaps because pesticides have eliminated their food sources 

What can you do to cater to beneficial insects and other creepy crawlies? 

1. Attract beneficial insects to your yard, garden, or other landscape. Include a variety of native plants to provide a variety of food sources (like nectar and pollen).
2. Keep your lawn and other plants healthy. Give them appropriate amounts of water and sunlight, and do regular upkeep. A healthy ecosystem will have fewer pest outbreaks. 
3. Practice Integrated Pest Management (IPM) 
   • Identify the pest – make sure it’s not actually a beneficial! 
   • Decide how many of the pests are tolerable. Remember, some pests are necessary to feed beneficial insects and some plant damage is natural for any ecosystem. 
   • Think about using alternative control methods while you wait for the beneficial organisms to take over for you. Be patient, it can sometimes take several days for them to make a difference. Handle minor pest problems by hand-picking or dislodging them with a spray of water. 
   • If non-toxic methods aren’t enough, diagnose the problem first, then use insecticidal soaps, BT (Bacillus thuringiensis) or milky spore (two kinds of natural bacteria), or dormant oil sprays, as appropriate. 
   • Use pesticide only when other methods have failed. (Is it necessary or just cosmetic?) Pesticides can have disastrous unintended consequences for human health as well as the environment. Systemic pesticides, such as neonicotinoids, are absorbed by a plant’s vascular system, making the entire plant toxic to harmful and beneficial insects alike. If you choose to use a pesticide, consider selecting one that will target your pest specifically, rather than a broad-spectrum product. Choose the least toxic (EPA label says “caution”, rather than “warning” or “danger”). 
   • Buy only the amount you need, and apply the smallest amount needed to do the job. Follow the label exactly; overdosing will not do a better job; it will only cost you more and risk poisoning you or contaminating your water. Apply only on calm, dry days when no rain is forecast for at least 24 hours. 
   • Avoid spraying pesticide over sidewalks, gutters, or other paved areas, where it can wash into waterways, or to bare ground or eroded soil. Never apply near wells or waterways. 

Most insecticides are like double-edged swords . . . they kill pests, but can kill beneficial insects as well. In general, the ones that are most detrimental to beneficial insects are the broad-spectrum insecticides that have long residual action. “Broad-spectrum” means they kill a very wide range of insect species. “Long residual” materials means the residue still kills insects that walk over the sprayed surface for many days after it is sprayed.

Additional Resources

• Beneficial Insects in New Hampshire Farms & Gardens - UNH Extension Service 
• Learn about your Pest - National Pesticide Information Center 
• Insect Pests of Home Lawns - UNH Extension Service 
• Beneficial Insects, Spiders, and Other Mini-Creatures in Your Garden: Who They Are and How to Get Them to Stay - WSU Extension

Thanks to the National Pesticide Information Center for images and much of this information.