Raccoons

Two things usually bring a raccoon to attention: a lawn with its turf rolled back, and a noise overhead. Both have a described signature, and the second one matters more, because UC IPM states that females in search of nesting sites may rip off shingles, fascia boards, or rooftop ventilators to get into the attic.

Exclusion comes before anything else on this page, because that is the order the sources put it in. One rule travels with it and is stated where it belongs rather than at the end: Iowa State University Extension says to ensure there are no raccoons already present in the chimney or anywhere else inside before starting sealing or exclusion steps.

What It Is

UC IPM identifies the adult raccoon as Procyon lotor, a stocky mammal about 2 to 3 feet long. Virginia Tech Extension notes that the scientific name translates to “washing pre-dog”, a reference to the lineage raccoons share with dogs and the belief that raccoons wash their food.

• Length. UC IPM gives about 2 to 3 feet. Nebraska Extension gives 26 to 40 inches, nose to tip of tail. Virginia Tech Extension gives a total length of 25 to 41 inches for males and 24 to 36 inches for females, noting males are typically 10 to 15 percent heavier. The Missouri Department of Conservation gives a total length of 21 and a half to 38 inches with a tail of 5 to 12 inches.
• Tracks. Utah State University Extension states that the hind print is 3 and a quarter to 4 and a half inches long, much longer than wide.
• Climbing. Nebraska Extension states that raccoons are exceptional climbers, able to scale trees, chimneys, and downspouts.
• The opening they need. Nebraska Extension states that opossums need an opening that is at least 3 inches wide, while raccoons need at least 4.

On weight the four sources differ, and each figure is given here as its own institution states it. UC IPM gives 7 to 30 pounds. Virginia Tech Extension gives between 10 and 20 pounds, adding that the occasional large individual can weigh as much as 30 pounds. Nebraska Extension gives 7 to 35 pounds, noting weight varies dramatically as they fatten up for winter, and that on rare occasions raccoons weigh up to 50 pounds. The Missouri Department of Conservation gives 6 to 25 pounds. No figure is preferred here and none is averaged.

What the Damage Looks Like

The lawn signature is peeling, not digging, and UC IPM states the diagnostic directly. It states that raccoons do not typically dig holes in lawns when looking for food, and that if you see conical-shaped holes in your yard, this is likely the result of skunk foraging. What raccoons do instead is described the same way by three sources.

• UC IPM states that raccoons often will roll up newly laid turf when looking for worms and grubs.
• Nebraska Extension states that, unlike skunks, which create precise cone-shaped depressions when digging, raccoons will roll up or shred the sod in search of food. The same source states that raccoons, rarely opossums, damage turfgrass in search of worms and grubs.
• Iowa State University Extension describes strong, dexterous fingers that let them roll up turf in search of grubs.

Above ground level the damage is structural. UC IPM states that attics, chimneys, and the spaces beneath houses are also used as dens if access can be gained, that uncapped chimneys are often used as den sites, and that females in search of nesting sites may rip off shingles, fascia boards, or rooftop ventilators to get into the attic. Nebraska Extension states that raccoons are known to tear through attic vents. Utah State University Extension states that they will frequently enter uncapped chimneys and raise their young on the smoke shelf or the top of the fireplace box until weaning.

• Inside the attic. UC IPM states that insulation on walls may be torn up and displaced, and that raccoons may begin using an area of the attic for a latrine, with the ceiling beneath becoming stained and an objectionable odor accompanying it.
• Bins. Virginia Tech Extension states that they rummage through unsecured trash bins in search of food, often leaving a mess. UC IPM states that they scavenge from garbage cans and compost piles.
• Corn. Iowa State University Extension describes partially eaten ears of corn with the husks ripped back and stalks broken in multiple places.
• Poultry eggs. Iowa State University Extension states that eggs are generally consumed at or near the bird confinement, so broken shells can be evidence of raccoon activity.
• Droppings. Nebraska Extension states that raccoon and opossum feces will generally be cat-sized and filled with remains of their varied diet.

Control: Exclusion First

Three sources put exclusion first. UC IPM states that exclusion is the key to eliminating den sites, and Iowa State University Extension states that exclusion is the first line of defense against raccoons. Utah State University Extension puts it as a judgement of its own, quoted here with its qualifying clause intact: “Exclusion, if feasible, is usually the best way to handle raccoon damage”.

Before anything is closed up

• Check that nothing is inside. Iowa State University Extension says to ensure there are no raccoons already present in the chimney or anywhere else inside when starting sealing or exclusion steps.
• A female with young is a specific hazard. Utah State University Extension states that a female with young may attack if cornered, and advises caution if a mother and young are encountered in an enclosed space. UC IPM states more generally that raccoons are powerful animals and can become vicious when cornered.
• Virginia Tech Extension states that chimneys and attics are spaces commonly used to birth young, which is why the check above matters in spring rather than being a formality.

The specifications, as each source states them

• Under structures. UC IPM states that open spaces beneath porches, decks, and garden and tool sheds should be tightly screened with 10-gauge quarter-inch or one-third-inch galvanized hardware mesh.
• Crawl spaces. Nebraska Extension states that crawl spaces below sheds, porches, and decks should be secured using 1 inch by half-inch galvanized hardware cloth.
• Repair materials. Nebraska Extension names 10-gauge quarter-inch wire mesh, aluminum flashing, and solid half-inch wood or plywood.
• Fencing. Virginia Tech Extension states that an option for protecting field crops or garden plots is to install a wire mesh fence with openings less than 2 inches, and cautions that installing mesh fencing across uneven topography can be difficult because gaps will allow raccoons to slip under.
• Roof edges. Iowa State University Extension describes placing wide, slick sheet-metal along the edges of the roof.
• Openings generally. Virginia Tech Extension states that to reduce access to attics and crawl spaces you should locate and repair or seal up any openings that currently provide entry.

The two sources that give a burial depth do not agree, and both are given as they are written. UC IPM states that the bottom edge of the wire should be buried at least 6 inches deep, extended outward for 12 inches, and then back-covered with soil. Nebraska Extension states to bury the mesh at least 4 inches below the soil and create a 12 to 18 inch skirt under the soil to discourage digging. Neither figure is corrected against the other here, and neither is preferred.

Chimneys

Virginia Tech Extension states that installing an approved chimney cap made from sheet metal and heavy metal screening will secure the flue from raccoons and other wildlife. The same source attaches a condition that belongs in the same breath as the specification: before installing a chimney cap, homeowners must confirm that the cap they have selected is appropriate to the type of flue they have and that it meets all pertinent local building and fire codes. UC IPM and Utah State University Extension both describe uncapped chimneys as den sites, which is what the cap addresses. Virginia Tech Extension adds that skilled wildlife control operators can assist homeowners with chimney cap installation and exclusion work for a fee.

What Brings Them In

• Pet food. UC IPM states that pet food left outside overnight ranks high as a food resource, and that pet food left outdoors should be removed before nightfall. Virginia Tech Extension states that pet owners must ensure unconsumed pet food is not accessible outdoors, especially at night.
• Bins. UC IPM describes using metal garbage cans with secure lids. Nebraska Extension states that trash cans, preferably metal, should have tight-fitting lids that remain attached even if tipped over. Iowa State University Extension says to seal or clamp the tops of bins and lock down dumpster lids at night, and notes that an unfastened lid is simply an invitation. Utah State University Extension says to store garbage in metal or tough plastic containers with tight-fitting lids.
• Bird feeders. UC IPM states that bird feeders provide another dependable food source for raccoons. Virginia Tech Extension states that feeders placed within reach often become important and reliable sources of supplemental food.
• Compost. Nebraska Extension states that care should be taken to use only plant and vegetable matter, and no meat, eggs, fats, or oils, in compost piles.

Rabies and Raccoon Roundworm

On rabies, UC IPM states that raccoons are also carriers of rabies and distemper, and Utah State University Extension lists rabies among the things they may carry alongside fleas, ticks, lice, distemper and mange. Virginia Tech Extension puts it more strongly, and its wording is quoted rather than restated: “Raccoons remain the primary vector through which exposure to rabies for humans exists — greater than with any other wildlife species.” That is Virginia Tech Extension’s assessment, attributed to them.

Raccoon roundworm is the second concern and it is the one with a cleanup procedure. Virginia Tech Extension describes Baylisascaris procyonis as a parasite that can pose a potential threat to human health, residing in the intestines of infected raccoons where it produces millions of eggs that are shed in the feces. Washington State Department of Health states that Baylisascaris worms grow inside raccoon intestines, where they produce eggs that are passed in the feces.

• Latrines. Washington State Department of Health states that raccoons defecate in communal sites, called latrines, that many raccoons may use the same latrine, and that latrines are often found at the bases of trees, in unsealed attics, or on flat surfaces such as logs, tree stumps, rocks, decks, and rooftops. Ohio State University states that most latrines are small and are usually produced by a single raccoon during a season.
• How people are infected. Wisconsin Department of Health Services states that people become infected by ingesting infectious eggs. Washington State Department of Health states that people and animals can become infected when they ingest these eggs in soil, sand, water, or on objects contaminated by raccoon feces.
• The eggs are not infectious straight away. Wisconsin Department of Health Services states that eggs passed in raccoon feces are not immediately infectious. Washington State Department of Health states that after 2 to 4 weeks in the environment, these eggs become infectious to humans and other animals, including dogs. Virginia Tech Extension adds that the eggs have a very sticky and persistent coating that is difficult to remove or inactivate.
• Who is most at risk. Washington State Department of Health states that most infections occur in young children or persons with developmental disabilities who are more likely to put contaminated objects, dirt, or sand in their mouth.
• Where it has been found. Washington State Department of Health states that raccoons infected with Baylisascaris procyonis have been identified across the United States, including in Washington state, as well as in other countries.

On cleanup, the agencies are specific. Wisconsin Department of Health Services states that if raccoons have set up a den or a latrine in your yard, raccoon feces and material contaminated with raccoon feces should be removed carefully and burned, buried, or sent to a landfill. Washington State Department of Health states to wear disposable gloves, to wear an N95 respirator, to avoid stirring up dust by spraying the area with water from a spray bottle before cleaning, and to remove feces and contaminated material and burn, bury, or double bag it. Virginia Tech Extension describes the same protective equipment as a respirator, disposable gloves and coveralls, needed to avoid inhaling airborne particles or having direct contact with eggs embedded in fecal matter. Nebraska Extension adds a specific warning for chimneys: if having the chimney cleaned, do not allow the vacuum cleaner to vent inside your home, as it may spread raccoon roundworm eggs throughout the room. Washington State Department of Health states to wash hands with soap and warm water after working or playing outside.

Two prevention lines come from the same agency. Washington State Department of Health states to keep brush clear so raccoons do not make a den on your property, and that if you have an attic, crawlspace, or basement you should ensure possible entrances are closed — which is the exclusion section above, arrived at from the health side.

When They Are Active

Four sources describe the same pattern. UC IPM calls it a nocturnal animal and notes that because they are active mainly at nighttime, raccoons are often present but may go undetected for some time. Iowa State University Extension gives active mostly at night and around dawn and dusk. Nebraska Extension states that raccoons and opossums are nocturnal. Utah State University Extension states that because they are active at night, they are seldom seen.

Virginia Tech Extension records the exception in its own words, describing raccoons as nocturnal, meaning active mostly at night, but stating that individuals occasionally will be active during daylight hours. The same source states that chimneys and attics are spaces commonly used by raccoons as daytime resting spots, so an animal seen leaving a roof in daylight is doing something the literature describes.

No source consulted for this page states that a raccoon seen in daylight is sick. Virginia Tech Extension describes daytime activity in ordinary animals, and nothing read for this page connects a daylight sighting to illness of any kind.

On the year, UC IPM states that raccoons are active year round but may take cover in dens during periods of severe winter weather, and Virginia Tech Extension states that they remain active year-round but may shelter in a den for several consecutive days during extreme cold.

Breeding and Young

Virginia Tech Extension states that most mating occurs during February and March, and that kits are born about two months later in April and May, completely dependent on the female for eight to 10 weeks. UC IPM states that young are generally born in April or May, but that earlier and later litters are not uncommon. The Missouri Department of Conservation states that most breeding occurs in February and most litters are born in April or early May, though some litters are born as late as August, and that the young are usually weaned by August but stay with their mothers until the next spring.

On how many young, the three sources give three different figures, and all three are reported as their sources state them. UC IPM gives a litter size ranging from three to six young, averaging about four. Virginia Tech Extension gives one to eight kits, with an average of three to four. Nebraska Extension gives 2 to 5 young. None is preferred here.

Questions

Sources

Every factual claim above names the source it rests on, in the sentence that makes it or in the text immediately adjacent to it, and every source named is listed below. Framing, ordering and emphasis are our own judgement and are not a finding of any source. Where sources give different figures for the same measurement, all are reported and attributed rather than averaged.

1. UC Statewide IPM Program. Raccoons — Pest Notes, Home and Landscape. Accessed 22 August 2026. https://ipm.ucanr.edu/home-and-landscape/raccoons/
2. Iowa State University Extension, Natural Resources. Raccoons: Damage Management. Accessed 22 August 2026. https://naturalresources.extension.iastate.edu/encyclopedia/raccoons-damage-management
3. Virginia Cooperative Extension, Virginia Tech. Managing Human-Wildlife Interactions: Raccoons (Procyon lotor), CNRE-148. Accessed 22 August 2026. https://www.pubs.ext.vt.edu/CNRE/cnre-148/cnre-148.html
4. Nebraska Extension, University of Nebraska–Lincoln. Controlling Raccoon and Opossum Damage. Accessed 22 August 2026. https://cms.unl.edu/ianr/extension/wildlife/sites/unl.edu.ianr.extension.wildlife/files/media/file/controlling-raccoon-opossum-damage.pdf
5. Utah State University Extension. Raccoons Raiding Your Garden and Garbage. Accessed 22 August 2026. https://extension.usu.edu/archive/raccoons-raiding-your-garden-and-garbage
6. Missouri Department of Conservation. Raccoon field guide. Accessed 22 August 2026. https://mdc.mo.gov/discover-nature/field-guide/raccoon
7. Wisconsin Department of Health Services. Baylisascaris procyonis. Accessed 22 August 2026. https://www.dhs.wisconsin.gov/disease/baylisascaris-procyonis.htm
8. Washington State Department of Health. Baylisascariasis (Raccoon Roundworm). Accessed 22 August 2026. https://doh.wa.gov/you-and-your-family/illness-and-disease-z/baylisascariasis
9. Wisconsin Department of Natural Resources. Raccoon roundworm. Accessed 22 August 2026. https://dnr.wisconsin.gov/topic/wildlifehabitat/disease/Raccoonroundworm
10. Ohio State University, Woodland Stewards. Raccoon Roundworm, fact sheet W-20-08. Accessed 22 August 2026. https://woodlandstewards.osu.edu/sites/woodlands/files/d6/files/pubfiles/W_20_08%20raccoon%20roundworm.pdf
11. Cornell Wildlife Health Lab, Cornell University. Baylisascaris fact sheet. Accessed 22 August 2026. https://cwhl.vet.cornell.edu/sites/default/files/2024-12/cwhl-fact-sheets_baylis.pdf