Requirements of Predators and Parasites

Food. Many natural enemies of pests and weeds rely 

on plants for growth, development, and reproduction. They may feed on pollen, nectar, seeds, sap, 

or plant parts, or consume the honeydew produced 

by other insects. Some eat additional, non-pest prey 

living on plants in and around the farm.

Shelter. Many natural enemies—both vertebrates 

and invertebrates—require specific plant habitats 

for nesting or overwintering, or to provide favorable 

micro­climates such as lower temperature or higher 

humidity in the summer. If criticalre­quirements are 

missing at key stages in the life cycle of insects, birds, 

or bats, they will not stay on your farm.

Protection from pesticides and disturbance. Insecticides may be toxic to predatory and parasitic species; 

herbicides may remove critical plant resources; and 

intensive cultivation may reduce population densities of these beneficial organisms.

Principles of Farmscaping for Natural Enemies

1. Determine which species are most likely to be 

helpful. Find out which predators and parasites feed 

upon the pests that attack your crops, the time of 

year they are active, and the habitat resources (food 

and shelter) that they need.

2. Know and map farm habitats. Identify fields and 

margins—and the times of year—where habitat resources for these beneficial species are lacking.

3. Manage your farm to attract and retain natural 

enemies. Use the illustration in this brochure as a 

guide to protect and enhance valuable habitat and 

to add appropriate plants and other features.

Getting Started

Here are two things you can do to improve the situation for natural enemies of pests and weeds:

Start small by experimenting with a single tactic. 

Estab­lish an insectary flower border or block, as 

illus­trated in this bro­chure, in a readily accessible 

location. Observe this habitat regularly to determine 

whether beneficial species are present when they 

would be most helpful on your farm.

Avoid a harmful practice. Choose an alternative 

pesticide that is not toxic to beneficial species, or 

experiment with reducing intensive cultivation in 

an area of your farm. Watch to see whether predators 

and parasites are more active in these areas. 

Going Further

The practices listed in this brochure will generally 

increase beneficial insects and reduce pest species. 

Many pests, however, also have specialized predators and parasites that are highly efficient; these may 

require specific practices to attract and retain them. 

Consult with biological control experts such as extension workers or other growers to determine what 

you might do for these species on your farm. 

What to Expect

Many predator and parasite species have limited dispersal capacity and reproduction rates, and populations may therefore be slow to increase. Don’t be 

surprised if it takes more than one growing season 

for your habitat improvements to yield results. 

Habitat for Predators and Parasis

Many insects and spiders, as well as bats and 

birds, eat crop pests and weeds. Providing food 

and shelter for these useful animals can help 

suppress unwelcome pest spe­cies.

This brochure illustrates how farmers can attract and retain helpful predators and parasites 

by providing some of the key resources that they 

require. Many of these practices benefit pollinators and other wildlife as well, and are eligible 

for support by Farm Bill programs. 

Inside, you will find more information and 

a guide to help you manage your farmland for a 

wide variety of the beneficial insects that are the 

natural enemies of crop pests and weeds. 

Habitat for Predators and Parasites

Published by the Xerces Society in collaboration with the Integrated Plant 

Protection Center. Financial support provided by USDA Smith-Lever IMP (3d) 

funds and the USDA-NRCS. Text by Paul Jepson and Mace Vaughan. Illustrations by Andrew Holder. Designed and produced by Press-22. Copyright 

© 2007 by the Xerces Society, an equal-opportunity provider and employer.

The Xerces Society for Invertebrate Conservation

628 NE Broadway, Suite 200, Portland, OR 97232

855-232-6639 www.xerces.org

I establish beneficial insect habitat because it 

makes me money. For example, increased predator activity has allowed me to eliminate sprays for 

black cherry aphid.

—Mike Omeg

Omeg Family Orchards

The Dalles, Oregon

Striking a balance between beneficial organisms 

and pests is the key to biological pest management on our farm. We don’t want to kill off all 

the bad bugs. We want just enough out there to 

feed our good ones.

—John Eveland

Gathering Together Farm

Philomath, Oregon

More Information About Beneficial Insects

The Xerces Society is a nonprofit organization that 

protects biological diversity through conservation of 

invertebrates and their habitat. We work with farmers and scientists across the country to protect habitat for beneficial insects that pollinate crops and prey 

upon crop pests. More information about predatory 

and parasitoid insects is available on our website at 

www.xerces.org/conservationbiocontrol/. 

Financial and Technical Assistance

The USDA’s Natural Resources Conservation Service 

(NRCS) provides financial and technical assistance 

to support conservation efforts for pollinators and 

other beneficial insects on farms. For information 

on NRCS conservation programs, contact your local 

NRCS or conservation district office. The office nearest you can be located at www.nrcs.usda.gov.

FARM I NG

F OR 

PE ST MANAGEMENT

Invertebrate natural enemies include hoverflies, lady beetles, parasitic wasps, spiders, lacewings, predaceous mites, and pirate bugs.

The Integrated Plant Protection Center at Oregon 

State University houses the statewide Integrated 

Pest Management program. The Center also runs the 

Farmscaping for Beneficials program, which undertakes participatory research and education programs 

with farmers. More information about the Center 

can be found at http://ipmnet.org. 

integrated plant protection center

XS 0212
Native Trees

Food and Shelter

Alone or in windbreaks, trees such as conifers, willows, or 

maples provide resources, travel routes, and safe haven for 

predators, parasites, and insect-feeding birds year-round.

Perennial Shrubs

Food and Shelter

Native shrubs such as oceanspray, elderberry, or rose 

provide pollen, nectar, and homes for non-pest prey—as 

well as undisturbed habitat—for predators and parasites.

Sunflowers

Food and Shelter

Sunflowers support alternative prey and provide 

nectar and pollen for predators and parasites. 

They also offer escape cover for insect-feeding birds.

Insectary Field Borders and Strips 

Food and Shelter

A variety of strip plantings—blocks of calendula, alyssum, 

yarrow, or phacelia, for example—interspersed in and around 

crops are easily managed to provide resources for beneficial 

insects at the times and places where they are most valuable.

Harmful Practices

Cultivation, field burning, and broad-spectrum pesticides disturb or kill natural 

enemies and their non-pest prey. Reducing disturbance and using selective 

pesticides and non-chemical controls will help minimize impacts.

Bolting Crops

Food and Shelter

Retaining bolting or flowering crops for a 

while after harvest may provide beneficial 

insects with an important nectar source 

when and where pests are active.

Insectary Blocks

Food and Shelter

Blocks planted with a variety of annuals and 

perennials such as rose, elderberry, or yarrow 

can provide resources throughout the year.

Beetle Banks

Food and Shelter

Creating permanent raised banks near 

fields, and densely planting them with 

bunch grasses, will provide overwintering 

habitat for predatory beetles and spiders.

Bat and Bird Nest Boxes

Shelter

Bats forage in the air above crops, where they feed upon the flying stages 

of insects, including pest species. Birds may eat insects and rodents. 

Providing nest boxes for these animals gives them a home on your farm.

Cover Crops

Food and Shelter

Including cover crops such as buckwheat and clover in planting 

rotations helps to build soil and add nutrients while providing 

patches of flowers to support predator and parasite populations. 

Wildflower Patches

Food and Shelter

Patches of volunteer annuals or innocuous 

weeds allowed to flower along field edges 

help provide an unbroken sequence of nectar 

and pollen during the growing season.

Conservation Cover

Food and Shelter

Sowing crop alleys or field roads with 

clover or other flowering plants can add 

soil nutrients and provide resources for 

predators and parasites through the year.