Pest Prevention: Maintenance
Practices and Facility Design
Effective pest management for schools depends on more than just a skillful pest control operator. The conditions that attract and support pests, that is, the presence of food, water, harborage, and access are often under the control of other individuals who may not think in terms of how their activities affect pest populations. For example, plumbers, electricians, custodians and others all have a role in managing pest problems. A successful prevention program should therefore include everyone involved in management and maintenance, as well as other school staff, teachers, and students.
Prevention is the key to effective, least-hazardous pest management programs in schools. If the conditions that attract and support pests are not eliminated, other control tactics are likely to prove ineffective or temporary. Below are some techniques that managers, staff, and contractors should understand and practice. Sources listed in the References section contain many additional suggestions.
- Remove lights on or near the building(s) that may attract night-flying insects.
- Maintain a plant-free zone of about 12 inches around buildings to discourage insects from entering.
- Design weep holes in window frames to prevent access by paper wasps. Design windows to prevent harborage and access for pests, with no clear passageways to inside.
- Correct structural features that provide opportunities for bird roosting or nesting.
- Avoid locating decorative lattices, that may inadvertently serve as bird roosts, over entrances to food services facilities.
- Install bird-proof barriers that are designed to prevent both pigeon and sparrow access to preferred nesting sites.
- Design exterior light fixtures so that birds cannot roost or nest on or in them.
- Fit eave roof tiles with bird stops (that will also exclude bats, bees and wasps).
- Correct structural features that provide opportunities for rodent harborage or burrowing.
- Screen or otherwise eliminate animal access under decks, porches, stairways. Seal porches and ramps to the building foundation with ¼-inch hardware cloth screen mesh to form a barrier to digging pests such as rats and skunks. This screen must extend 12 inches into the ground and must have a right-angled, 6 inches wide, outward extending shelf to prevent burrowing under the screen.
- Screen ventilation louvers with ¼-inch hardware cloth screen mesh to exclude birds, rodents, cats, etc., (coordinate with mechanical requirements).
- Maintain a 2-foot pea gravel strip around buildings to prevent rodent burrowing.
- Use a 3" layer of sand for the sand barrier underneath slab construction. Use 1-3 mm particle size in place of unsifted sand to provide a permanent sand barrier to termites (both western subterranean and Formosan termites). This will prevent termites from penetrating cracks in slab construction.
- Place outdoor garbage containers, dumpsters, and compactors on hard, cleanable surfaces and away from building entrances (at least 50 feet from doorways). Design site with properly graded concrete or asphalt pads to help prevent rats from establishing burrows beneath them.
- Design site with solid enclosure that extends all the way to the ground. Use metal or synthetic materials, as opposed to chain-link, wood, etc. to prevent rodents from gnawing and climbing the enclosure.
- If trash will be stored, design storage areas that can be closed off from the rest of the building.
- Locate storage areas for boxes, paper supplies, and other materials in areas separate from where food or trash is stored. When stored together, these materials put food and shelter together, favoring pests.
- When selecting plants, choose proven performers, plants known to do well in the area intended for planting. Avoid those known to have a history of pest problems. Use resistant plant species and cultivars when available. Check with your university or cooperative extension service for recommendations.
- Give preference to plants that shed a minimum of seeds and fruits, since the seeds and fruit may attract and support insects, rodents, and undesired birds.
- Design with diversity. Include a wide variety of plants in the landscape to reduce the pest damage potential.
- Provide a properly prepared site. Site selection is critical; the
site must be compatible with the plants' requirements.
- Design landscaped areas with flexibility to allow for campus additions, which may change drainage, exposure to sunlight, ventilation, or other plant requirements.
- Avoid crowding of landscape plantings.
- Group plantings with similar cultural requirements.
- Install or retrofit fence lines and other turf or landscape borders with cement mowing strips.
- Avoid planting vegetation directly against buildings as this provides shelter and sheltered runways for rodents. For the same reason, avoid planting dense vegetation that completely covers the ground.
- Do not plant vines which climb building walls, as these create runways for rodents and harborage for undesired bird species.
- Plant trees away from buildings to prevent easy access to buildings for insects and rodents.
- Give careful consideration to placement of deciduous trees. Leaves which accumulate along foundations provide harborage and sheltered runways for rodents.
- Ensure that new kitchen appliances and fixtures are of pest-resistant design, i.e., open design, few or no hiding places for roaches, freestanding and on casters for easy, thorough cleaning.
- Provide space under and around appliances and equipment in kitchen areas to allow maximum ventilation and ease of (steam) cleaning.
- Use coving at floor-to-wall junctures to minimize build-up of debris and to facilitate cleaning.
- Slope floors in kitchen areas to provide good drainage after cleaning.
- Do not install pegboard in kitchens, animal rooms, or laboratories.
- Insure that all pipe insulation has a smooth surface and that there are no gaps between pieces.
- Refrigerate trash/recycling storage rooms.
- Ensure that new office and classroom furniture that is rarely moved (e.g., staff desks, bookcases, filing cabinets) is designed to permit complete cleaning under and around the furniture, or to allow ready movement for cleaning purposes.
- Design or retrofit construction to provide adequate ventilation, preventing trapped moisture and condensation.
- Equip area with self-closing doors.
- Keep vegetation and wood mulch at least 12 inches away from structures, and away from breathing vents of foundation.
- Keep tree limbs and branches that might provide vertebrate pest access to buildings at least six feet away from building exteriors (ten feet if tree squirrels are a problem).
- Seal all plumbing and electrical service entrances.
- Seal all access to bird nesting sites.
- Keep doors closed tightly; equip doors with self-closures and door sweeps.
- Repair all broken panes in windows and/or skylights.
- Monitor buildings for access holes, and repair/seal all holes, cracks, and crevices to discourage hiding places or entry points for pests.
- Clean up wooden debris from under and around structures.
- Eliminate all soil-to-wood contact. Stack pallets off the ground and away from building.
- During landscape renovation, do not raise the soil level against the building.
- Avoid placement of discarded equipment and/or materials next to building(s).
- Store materials and equipment on elevated racks at least 12 inches off the ground.
- Clear weeds, grass and brush from building perimeters and from fence lines.
- Keep walls reasonably clean and free of dust, moss, and debris.
- Ensure that paving is in good repair.
- Discourage feeding of birds and other wildlife on campus.
- Discourage feeding of feral dogs and stray domestic cats on campus.
- Prevent sprinklers from wetting stucco.
- Keep area under structures dry. Maintain proper drainage away from structures.
- Keep drains clean so water flow is unimpeded.
- Inspect roofs and basements periodically to insure that there is no standing water or flooding. Where problems recur, frequent inspections are necessary.
- Where feasible, install gravel on the area around foundations and grade these areas away from the building to avoid basement flooding.
- Prevent shrubbery from blocking breathing vents in the foundation.
- Allow food and beverages only in limited designated areas.
- Ensure that there is no spillage or trash that may attract pests.
- Regularly sweep and/or steam clean outdoor lunch areas.
- Equip all outdoor garbage containers with plastic liners.
- Equip all outdoor garbage containers with tight-fitting, spring-loaded lids to exclude pests.
- Elevate trash receptacles off the ground where possible to prevent rodent access.
- Empty garbage cans in outdoor lunch areas immediately after lunch and remove any food debris on the ground, so that insects, rodents and birds will not be attracted to the site.
- Empty outdoor garbage containers frequently to prevent accumulated trash, particularly near doorways.
- Collect and properly dispose of litter from all school ground areas at least once weekly.
- Collect and move recyclables and stored waste off site at least once weekly.
- Clean all garbage cans and dumpsters regularly. Wash outdoor garbage containers on at least a monthly basis, including spill-contaminated areas around containers.
- Eliminate standing water on school grounds that may attract pests. Correct improper grading and poorly functioning drainage that may lead to standing water.
- Remove containers, potholes, and other features that collect water.
Turf weed control is best approached with preventive strategies, emphasizing maintenance of healthy turf. This involves proper selection of turf grass species for each environmental setting; proper irrigation, fertilization, drainage, mowing and aeration; and proper selection and placement of ornamentals which will not limit turf growth. Check with your university or Cooperative Extension service for recommendations on turf types and management practices.
- Raise mowing height for turf to enhance its competition with weeds; adjust cutting height of mower, depending on the grass type; sharpen mower blades; and vary mowing patterns to help reduce soil compaction.
- Water turf infrequently but sufficiently during morning hours to let turf dry out before nightfall; let soil dry slightly between watering. Check with your local Resource Conservation District or Cooperative Extension service for information on soil types and watering needs in your area.
- Provide good drainage, and periodically inspect turf for evidence of insect pests or diseases.
- Allow grass clippings to remain in the turf (use mulching mower or mow often) or compost clippings with other organic material.
- Test soil to determine pH and fertilizer requirements. Time fertilizer application appropriately to prevent problems caused by excessive fertilization.
- Use a dethatcher to remove thatch. Do this in early fall or early spring when over-seeding operations are likely to be most successful.
Pest prevention in landscape plantings is best accomplished with a strong emphasis on proper plant selection, placement, and care.
- Prevent water stress in plants. Avoid over-watering. Wherever possible, group plantings with similar water and other maintenance requirements. Maintain the optimum moisture requirements for each plant type.
- Use the appropriate pest-resistant plant variety. Select replacement plant material that is disease-free, disease resistant, and locally adapted (check with your local Cooperative Extension service).
- Use correct planting techniques. These are an invaluable investment in the future health of plants.
- Use established soil fertility management practices.
- Avoid mechanical injury to plants.
- Remove wind-damaged branches.
- Use sanitation practices including the removal of diseased plants, pruning infected parts of plants, and removal of diseased branches.
- Remove susceptible plants if a plant disease recurs and requires too many resources to treat.
- Maintain smooth floor surfaces free of cracks and holes. Repair cracks and crevices in walls, floors and pavement.
- Keep exterior doors throughout the building closed when not in use.
- Place weather stripping and door sweeps on doors to exclude pest entry.
- Seal openings around potential insect and rodent runways (electrical conduits, heating ducts, plumbing pipes).
- Caulk permanent bulletin boards, mirrors and other wall fixtures.
- Screen floor drains.
- Allow food and beverages only in designated areas.
- Communicate pest management roles to staff and students, including removing food or food wrappers from lockers and desks on a daily basis.
- Remove any leftover food items from classrooms (e.g., snack food in kindergartens) or store in sealed containers.
- Remove accumulated debris along wall/floor junctures, on top of equipment, etc.
- Keep food or other perishable products away from walls.
- Collect and remove waste materials in all rooms within the school building to a dumpster, compactor or designated pickup location daily.
- Promptly and properly dispose of, or recycle, packing and shipping trash (bags, boxes, pallets).
- For animal wastes (from classroom pets or laboratory animals), either flush down toilet or place in sealed containers before disposal.
- Empty and thoroughly clean lockers and desks at least twice per year (e.g., winter break and at the end of each school year).
- Give furniture in classrooms and offices that is rarely moved (e.g., staff desks, bookcases, filing cabinets) a thorough cleaning around and under to remove accumulated lint, etc., at least annually.
- Ensure that the inside of vents and ducts are inspected at least every three years and cleaned when needed by a certified contractor.
- Remove out-of-date charts or paper notices from walls monthly.
- Maintain walls and windows free of dust, cobwebs, etc.
- Frequently vacuum carpeted areas.
- Maintain clean drains.
- Keep areas as dry as possible by removing standing waters and water-damaged or wet materials.
- Correct moisture sources (e.g., ventilate areas where condensation forms frequently, repair plumbing, roof leaks, dripping air conditioners).
- Keep sewer and water lines in good repair.
- Close off unused drains or drainpipe openings.
- Seal pipe chases.
- Clean floor drains, strainers, and grates on a regular basis.
- Promptly repair leaks and correct other plumbing problems to deny pests access to water.
- Keep areas dry. Avoid conditions that allow formation of condensation. Increase ventilation if necessary.
- Inspect pipes and other sources of water, such as restrooms, kitchens, or climate-control equipment, routinely to guard against leakage.
- Wrap sweating pipes with insulating tape.
- Store paper products or cardboard boxes away from moist areas and direct contact with the floor or the walls.
- Seal all permanently installed furniture in kitchens and laboratories at points of attachment, under counter tops, and inside to prevent harborage of pests in the gaps. All built-in cabinets, closets and similar casement/millwork must be sealed, leaving no gaps for pests to hide in.
- Create inhospitable living conditions for pests by reducing availability of food and water.
- Allow food and beverages only in limited, designated areas.
- Store food in containers that are inaccessible to pests. Containers must have tight lids and be made of plastic, glass, or metal.
- Store and seal food waste (from preparation and serving areas) in plastic bags before removal. Waste should be removed at the end of each day.
- Keep indoor garbage in lined, covered containers and empty daily.
- Drain waste with liquid food residues (e.g., milk cartons, juice boxes)
of excess moisture before discarding.
Use disposable wiping cloths or launder daily.
- Properly dry and store mops and mop buckets (e.g., mops hung upside
down, buckets emptied).
- Maintain vending machines in clean condition inside and out.
- Clean spills and repair leaks promptly in trash/recycling rooms, compactors and dumpsters.
- Regularly clean surfaces in food preparation and serving areas of any grease deposits.
- Thoroughly clean around and under appliances and furnishings in these areas that are rarely moved (e.g., refrigerators, freezers, shelve units) to remove accumulated grease, dust, etc., at least monthly.
- Clean food-contaminated dishes, utensils, and surfaces by the end of each day.
- Clean floors and vacuum carpets daily in areas where food is served, and at least weekly in other areas.
- In food service areas, remove drain covers and clean drains weekly (e.g., with a long-handled brush and cleaning solution). In other areas, such as drains under refrigeration units, clean drains monthly.
- Keep floor and sink drain traps full of water.
- Maintain an inspection procedure for all receivables, and establish procedures for rejecting carriers with evidence of pest contamination or infestation.
- Close dock doors when not in use.
- Keep the area beneath dock levelers clean.
- Do not stack materials against walls in receiving areas.
- If supplies are uncased in the receiving area, take empty cartons and cases to the trash disposal or recycling area immediately.
- Place received goods on clean shelves or mobile storage carts.
- Eliminate spillage.
- Maintain clean shelves and ledges.
- Promptly remove contaminated or infested merchandise from the area and facility.
- Store products on pallets or open shelving.
- Minimize clutter in storerooms and classroom storage areas.
- Avoid storing food or potential nesting materials in cardboard boxes for extended periods of time.
- Use metal shelving for storage. Metal is preferable to wood for shelving because it is easier to clean and does not absorb spilled materials.
- Keep pallets at least 18 inches away from the walls.
- Ensure that there is no evidence of broken or exposed product(s) in stacks.
- Look for signs of insects or rodents near supporting posts of shelving or on overhead beams.
- Quickly dispose of all products spoiled by damage, insects, rodents, or other causes to remove potential pest breeding places.
- Maintain carrier vehicle floors and walls in good condition.
- Rotate stored products on a "first in, first out" basis to reduce potential for pest harborage and reproduction.
- Maintain inspection aisles (> 6 inches x 6 inches) around bulk stored products. Do not permit bulk stored products direct contact with walls or floors to allow inspection and reduce pest harborages.
- Store potential pest food items used in classrooms (e.g., beans, plant seeds, pet food and bedding, decorative corn, gourds) in refrigerator or in glass or metal containers with pest-proof lids.
- Store food products (except those to be used immediately) in refrigerators or in pest-proof containers, not in cardboard boxes.
- Wash with soapy water empty food/beverage containers before storage to remove food residue.
Integrated Pest Management Kit for Building Managers. Massachusetts Department of Food and Agriculture, Pesticide Bureau, 100 Cambridge Street, Boston Mass 02202. http://www.pestinfo.ca/documents/IPMkitforbuildingmanagers.pdf
IPM Institute of North America, Inc. Part I. IPM Standards for School Buildings, http://www.ipminstitute.org/school_buildings.htm
IPM Institute of North America, Inc. Part II. IPM Standards for School Grounds, http://www.ipminstitute.org/school_grounds.htm
Responsible Pest Management: Best Practices and Alternatives
U.S. EPA, Pest Control in the School Environment: Adopting Integrated Pest Management. http://www.epa.gov/pesticides/ipm/brochure/
Wisconsin's School Integrated Pest Management Manual, Section 1: Essential
Elements of IPM