Insect Identification and Control
To effectively control insect pests, you first have to be able to identify them. Use Penn State Extension’s resources and learn how to manage and control a variety of pests. Find information on leaf miners, spiders, mosquitos, mites, beetles, ticks, cockroaches, termites, wasps, hornets, slugs, earwigs, grubs, aphids, lanternflies, weevils, maggots, centipedes, and stinkbugs. Learn more about integrated pest management (IPM), and its practical application in the field, the backyard, or at home.
Insect Identification
The first step in adopting an integrated pest management system is proper pest identification, whether the pests are in the home, an equine facility, garden landscape, or an agricultural setting. Pests can also be a problem in high tunnels, red clover stands, and in soybean production. Help is available from experts such as Michael Skvarla, director of the Insect Identification Lab at Penn State’s College of Agricultural Sciences. Alternatively, you can learn to identify, prevent, and control the most common urban pests yourself.
Some of the most common insect pests include:
- Wood-destroying pests: Hymenoptera, such as bees, ants, and wasps, and wood-infesting beetles, subterranean termites, and other termites can cause severe damage to structural timbers in buildings.
- Mosquitoes: You can find more than 60 species of mosquitoes in Pennsylvania. The most widespread are the common house mosquito, white-dotted mosquito, rock pool mosquito, and the eastern tree-hole mosquito.
- Cockroaches: We commonly find three types in the US. You can control the American, Oriental, and German cockroaches by eliminating what they need to survive, such as food, water, and shelter.
- Spiders: You can find two dangerous spiders in Pennsylvania. Both the black widow spider and the brown recluse spider have a bite that may produce serious medical implications for humans.
- Stinkbugs: Not known for causing harm to humans, a large number of them flying around in your home can be distressing and if you squash them, they’re very smelly.
- Leaf miners: The larvae of these insects cause the damage. They mine their way through leaves and create blisters, hence the name. Vegetables most susceptible to this type of injury include beet, spinach, and chard.
- Tree fruit insects: The biggest issue with insects such as yellow jackets and hornets is the number of farmworkers who get stung. The general public is also at risk in farm markets and U-Pick operations.
- Spotted lanternfly: This is an invasive species that has spread throughout Southeastern Pennsylvania and nearby states.
Insect Pest Management and Control
Insect pests can cause substantial losses to crops and other types of plants. They can also cause human and animal diseases. For many years we have been dependent on pesticides as the only method of control, which has led to insect resistance and adverse effects of the environment, natural enemies, and human health. As a result, the ideal method for insect pest management and control is Integrated Pest Management.
Integrated Pest Management follows eight fundamental principles. These are:
- Prevention and suppression
- Monitoring
- Decision-making
- Non-chemical methods
- Pesticide selection
- Reduced pesticide use
- Anti-resistance strategies
- Evaluation
A key element for all these principles is identification. There are lots of resources available for both homeowners and commercial enterprises.
For homeowners and agriculture and green-industry professionals concerned about the spotted lanternfly, Penn State Extension has created multiple identification and management resources.
There are 900 species of ticks worldwide, 25 of which you can find in Pennsylvania. Penn State Extension provides an identification service and 90% of requests relate to two of these tick species.
East subterranean termites often cause damage to the structural timbers in buildings. Understanding their life cycle and the structural and chemical methods of control means you can reduce an infestation risk.
Integrated Pest Management can also be used to identify and control ants. The methods used are less hazardous to human health, less toxic to non-target organisms, easier and more cost-effective, plus are more likely to be effective in the long-term.
Mosquitoes are another common problem. They play a role in transmitting the West Nile virus, and one effective way to control them is to reduce potential mosquito breeding sites. Reducing the number of potential nesting sites is also a key element in spider management. For stinging insects such as paper wasps and yellow jackets, insecticides provide very effective control. If you’re using restricted-use, state-limited-use pesticides and regulated herbicides you will need a pesticide applicator license.
The monitoring of insect populations is one of the eight basic principles of IPM. You can monitor certain insects in the orchard using pheromone traps.
An increasing number of insect and mite pests have developed varying resistance levels to some of the insecticides commonly used. This has led fruit growers to adopt alternative approaches such as biological control by predators, pathogens, and parasitoids.
In this section, find plentiful resources on insect pest identification and management practices.
- Articles
Eastern Spruce Gall Adelgid
The eastern spruce gall adelgid is a key pest of Norway spruce, Picea abies, in northeastern United States. - Articles
Eastern Subterranean Termites
Eastern subterranean termites are present throughout Pennsylvania and often damage structural timbers in buildings. - Articles
Baldfaced Hornet
The baldfaced hornet is not a 'true' hornet - it is an 'aerial yellowjacket,' one of 7 or 8 species in the genus Dolichovespula in North America - Articles
Honeylocust Plant Bug
The honeylocust plant bug is a key pest of honeylocust. It is a particular concern with the thornless cultivars grown in nurseries and used in landscapes. - Articles
Hemlock Woolly Adelgid
In much of Pennsylvania, the hemlock woolly adelgid has caused significant damage to eastern hemlock in ornamental plantings and the forest. - Articles
Colorado Potato Beetle
Colorado potato beetle (CPB) feeds exclusively on solanaceous crops and weeds, and can be a significant pest of potatoes, tomatoes and eggplant. - Articles
Carpenter Ants
The black carpenter ant normally nests in logs, stumps, and hollow trees. However, the workers often invade homes in search of food. - Articles
Cluster Flies
In the autumn, cluster flies frequent the sunny sides of homes in search of protected over-wintering sites and may be found inside throughout the winter. - Articles
Cat Fleas
The cat flea, Ctenocephalides felis, is the primary flea found on cats and dogs. It will attack other animals and humans as well. - Articles
Brown-banded Cockroaches
Four species of cockroach are common pests in Pennsylvania structures. These are the German, brown-banded, Oriental, and American cockroaches. -
- Articles
Oystershell Scale
The oystershell scale is a common armored scale insect that causes injury to shade trees and shrubs, most often lilac, ash, dogwood, maple, poplar, and willow. - Articles
Oriental Cockroaches
One of four cockroaches common in Pennsylvania structures, Oriental cockroaches are often called water bugs due to their preference for dark, damp, and cool areas. - Articles
White Pine Weevil
The white pine weevil is considered the most destructive insect pest of eastern white pine in North America. - Articles
Spruce Spider Mite
The spruce spider mite attacks spruce, arborvitae, juniper, hemlock, pine, Douglas-fir, and occasionally other conifers. - Articles
Powderpost Beetles
Powderpost beetles breed in dead and dried hardwoods. Their presence may be overlooked until they are discovered in stored lumber, rafters, joists, floors, and furniture. - Articles
Grass-Carrying Wasp
Grass-carrying wasps construct nests from grass in tight areas, particularly in window tracks. They can be a minor nuisance but are easily ignored or removed if necessary. - Articles
Spotted Lanternfly Frequently Asked Questions
Get the answers to the most frequently asked questions about spotted lanternfly, including their damage to plants, how to manage them on your property, and what you can do to help! - Articles
Avoid Home Remedies to Control Spotted Lanternfly
Untested homemade solutions may harm people, pets, and plants. Their use can be unsafe and illegal. - Videos
Manejo Integrado de Plagas (MIP) en Huertos de Manzana
Length 9:46En este corto video, usted aprenderá principios básicos de exploración para enfermedades comunes en huertos – sarna o roña de la manzana - algunas plagas de ácaros y organismos benéficos. - Articles
Spotted Lanternfly Management Guide Supplement
Supplement for green industry professionals and natural resource managers on the spotted lanternfly and effective management strategies. - Articles
Potato Leafhopper on Alfalfa
The potato leafhopper is the most destructive insect to alfalfa in Pennsylvania, causing average annual losses of approximately $15 million. - Articles
What Should You Do With Spotted Lanternfly Egg Masses?
Information about locating, identifying, and treating egg masses. - Webinars
Free
Pennsylvania Invasive Species: Biosecurity
When 12/04/2026Length 1 hour, 15 minutesIntroductory webinar explores invasive insects, their spread, and impacts on agriculture and ecosystems, plus early detection and prevention steps for volunteers, professionals, and the public. - Webinars
Free
Pennsylvania Invasive Species: Lady Beetles
When 11/06/2026Length 1 hour, 15 minutesExplore the benefits and challenges of the multicolored Asian lady beetle and learn how this introduced species impacts homes, vineyards, and native ecosystems.




























