Integrated Pest Management

B.C. Pest Monitor — Former Newsletter of IPM in British Columbia

Vol. 4 No. 2 December 1995

Uninvited Guests: Preventing Deer Damage

The following article is from a BC Ministry of Agriculture, Fisheries and Food fact sheet
by Wayne C. Weber.

Deer are found throughout southern and central British Columbia, and are sometimes numerous enough to cause serious damage to commercial crops or home gardens. They usually cause damage by browsing on twigs, buds, and leaves of trees and shrubs, but sometimes eat the leaves of strawberries, vegetables, and other low-growing plants. Several methods have been developed for preventing or reducing deer damage.

Identification and Distribution

Two species of deer are native to British Columbia. The mule deer or black-tailed deer, occurs throughout southern and central B.C., and locally in northern B.C. Males typically weigh up to 180 kg, and females up to 70 kg, although coastal animals are smaller. The white-tailed deer is found mainly in the Okanagan and Kootenay regions and in the Peace River district. It is smaller than interior forms of the mule deer, with males weighing up to 135 kg and females up to 60 kg. All forms of the mule deer have black on the upper side of the tail, which is held down when running, in contrast to the white-tailed deer, which holds its tail aloft, showing the striking white underside. The mule deer buck has antlers which typically branch in two and then in two again, while the white-tailed deer has one main shaft from which the other tines branch off.

Habitat and Food Habits

Deer generally favour a mixture of forest and open country, which provides both food and protective cover. They are usually not abundant in dense forest, and often thrive in agricultural areas and on the edges of towns. The white-tailed deer often lives year-round in orchards, streamside thickets, and other low-elevation habitats. The mule deer often winters in the same Southern Interior valleys as the white-tailed deer, but it is more migratory and tends to summer at higher elevations.
Food habits of the two species of deer are similar. A wide variety of woody plants are eaten, with favoured species including aspen, willows, red-osier dogwood, snowbrush, and juniper. In summer, many herbaceous species are eaten, including several species of grasses.

Damage and Damage Identification

Most deer damage takes place from late fall through early spring, when wild foods may be in short supply. Buds and twigs of a wide variety of cultivated plants are eaten, but damage is most frequently reported to fruit trees, grapevines, rose bushes, and ornamental conifers, especially cedars. However, many kinds of garden plants tend to be avoided by deer, and if you live in an area where deer are abundant, it may be possible to minimize deer damage problems by carefully choosing plant species for your garden [see box below]

Deer will also eat leaves and buds of many garden plants during the growing season, although such damage tends to be less severe. Deer damage is usually easy to identify. Twigs eaten by deer usually show a ragged or torn edge, unlike those eaten by rabbits or rodents, which appear to be cleanly bitten off. In many cases, the damaged stems are at such a height that other garden pests can be ruled out. Even if deer are not seen, there are usually signs of their activity such as tracks or pellets of manure.

Legal Status

Deer are valued game animals, and are protected under the B.C. Wildlife Act except when being hunted during a legal hunting season. On very rare occasions, where deer are causing serious losses to commercial orchards or nurseries, and other damage control measures have been ineffective, kill permits may be issued or special limited-entry hunts may be held. However, kill permits would not be issued for deer damage to a home garden.

Damage Prevention and Control Methods

Two major methods of damage prevention or control are available for the home garden: fencing and chemical repellents. Fencing (especially woven wire or solid panel fencing) tends to be more effective, but is more costly; it should be considered if deer damage on your property is severe and/or persistent. Repellents, which are less costly but tend to be less effective, may be adequate if deer damage is infrequent and of light to moderate severity.

More Tips on Preventing Deer Damage

Peanut Butter Deer fence:

Where deer pressure is moderate, an economical, single-strand electric fence can be made into an effective barrier by baiting it with peanut butter. The deer are attracted by the peanut butter lures, which encourages nose-to-fence contact. After being shocked, the deer learn to avoid the fenced areas. The wire should be 75 cm (2 1/2 feet) off the ground. A 1:1 mixture of peanut butter and vegetable oil can be wiped directly onto the wire (renewing at monthly intervals) or applied to foil 'flags' at intervals. These are made from 7 x 10 cm rectangles of foil, attached to the fence from the underside by strips of cloth adhesive tape. Coat the adhesive tape with the peanut butter mixture and then fold the foil down over the peanut butter. When the deer nose into the bait to investigate they will receive a shock.

Soap Bars:

Recent studies and numerous testimonials have shown that ordinary bars of soap applied in the same manner as hair bags can reduce deer damage. Drill a hole in each bar and suspend it with a twist tie or soft cord. Each bar appears to protect a radius of about 1 metre. Any inexpensive brand of bar soap will work.

Hair Bags:

Human hair is an odor repellent that cost very little but has not consistently repelled deer. For readers wishing to try this out, place two handfuls of hair in fine-mesh bags (e.g., nylon stockings) and hang them on the outer branches of trees or from a fence or cord around the area to be protected. It is suggested that bags should be no more than 0.9 m (3 feet) apart and should be replaced monthly during the growing season.

Notes from: Prevention and Control of Wildlife Damage. 1994. University of Nebraska.

A. Fencing

A woven wire fence at least 2.4 m (8 feet) high, if solidly built, will normally exclude deer from a home garden. However, many deer will jump over a 1.8 to 2.1 m (6 to 7 foot) fence, so 2.4 m is recommended as a minimum height. An effective fence can be made from two 1.2 m (4-foot) widths of standard woven fencing attached together, and fastened securely to 3.6 m (12 foot) pressure-treated wooden posts, sunk 1.2 m (4 feet) into the ground. There should be no space between the fencing and the ground, or deer may crawl under the fence. The wire should be galvanized and have a maximum mesh size of 15 cm (6 inches). A good woven wire fence should last for 20 years.
Solid board or panel fences may provide effective visual barriers to keep deer out of home gardens. A solid fence 1.5 m (5 foot) high should be adequate, because deer will be unable to see plants inside the fence, and will not likely jump over it. Snow fencing has also been reported to be effective for small gardens up to 12 by 18 m (40 by 60 feet). Snow fencing is less expensive than woven wire, and will last many seasons.

Plants Deer (Usually) Do Not Eat

The following list is a guide only, as preferences can differ between local populations of deer and even between individuals. If deer are crowded or having difficulty finding forage, any type of garden plants may be eaten. Some plants may be nibbled in the spring, when new growth if forming, but will be ignored later.

Extracted from table in:
Sunset Western Garden Book (1995), Sunset Publishing Corp., Menlo Park, CA.

B. Repellents

Three types of deer repellents are registered for use in Canada. One of these, thiram, is a taste repellent; the other two, putrescent egg solids and an ammonia/fatty acids formulation, are odour repellents as well as taste repellents (trade names are given in parenthesis; their use does not imply endorsement of the product.) To ensure safety when using repellents, as with any other agricultural chemical, follow the instructions on the product label.

1. Products containing putrescent whole egg solids (DEER-AWAY or MGK BIG GAME REPELLENT), are an effective repellent. This may be used on dormant fruit trees and ornamental shrubs, but should not be used during the growing season, nor on vegetables or other non-woody plants.
2. A formulation of ammonia (HINDER), may be used on fruit trees, ornamentals, berry crops, and vegetables, in summer as well as in winter. However, do not apply this product to food crops within 14 days of harvest.
3. Thiram (SKOOT REPELLENT) is an effective repellent for rabbits as well as deer. The products may be sprayed or brushed on dormant trees and shrubs, but should not be used on flowers or vegetables.

A number of other substances have been tried as deer repellents over the years, including blood meal, human hair, mothballs and hot pepper. Although some of these substances may appear to be effective in some situations, none of them is a consistent enough repellent to be strongly recommended.

Living with Raccoons

Raccoons are found widely through the south coastal area, including Vancouver Island and parts of the Okanagan Valley. They prefer hardwood forest areas near water. Raccoons den in hollow trees, ground burrows, brushpiles, barns and other buildings, dense clumps of cattail or rock crevices. They eat both plant and animal foods. One litter of 3-5 young is raised per year. Most litters are born in April-May, but some females may not give birth until June, July or August.

Raccoons are nocturnal. They do not truly hibernate, but they do "hole up" in dens and become inactive during severe winter weather. While raccoons are not normally aggressive and rarely injure people, they can be dangerous when threatened or cornered. They are wild animals and should be treated accordingly.

Raccoon Damage and Prevention

Raccoons can cause considerable damage to vegetable gardens, particularly sweet corn. Freshly laid sod lawns are often rolled up in search of earthworms and grubs. They also kill poultry. In these cases, the best method of prevention is to deny them entry. Keep raccoons away from poultry with tightly covered doors and windows in buildings or mesh-wire fences with an overhang surrounding poultry yards. Raccoons are excellent climbers and can climb conventional fences or bypass them by using overhanging limbs. A "hot" wire from an electric fence charger at the top of the fence will greatly increase effectiveness. A one-wire or two-wire electric fence is best for large garden areas and lawns.

Keep smelly garbage in plastic bags indoors, or build a garbage shed. The lids on garbage cans should fit tightly. They can be secured with rubber straps and hooks, but these items should be removed before municipal employees collect the refuse. Putting a half cup of household ammonia in garbage bags also helps.

Raccoons cause damage or nuisance problems around houses and outbuildings when they try to enter attics, crawl spaces or chimneys. In extreme cases, they may tear off shingles or fascia boards. To keep them out, cover possible access points with heavy wire screening. Also, tree access to rooftops should be eliminated by pruning overhanging limbs and by placing a piece of tin loosely around the trunk, flaring it out like an upside-down funnel (also useful for keeping them out of fruit trees, if there is no other way into the tree).

Raccoons will eat fish in ornamental ponds. Wire screening over the pond is the best protection.

General Precautions

Do not put out food for raccoons or other wildlife and never leave pet food where wildlife can get it. Keep pets indoors at night. Dogs are not an effective method of keeping raccoons away.

Provincial conservation officers do not physically attend complaints on small problem wildlife unless there is a definite threat to the public. We offer advice and information on specific situations.

Raccoons are classified as furbearers under the Wildlife Act, and may be trapped in season by registered trappers who have a valid trapping licence. If you are in an area that is open to the discharge of firearms and you have a valid hunting licence, raccoons may be legally hunted. However, if you are in an area where the use of firearms is prohibited, raccoons may not be captured or killed without a permit.
The use of poison to kill any wildlife is illegal. Persons experiencing persistent or serious problems with raccoons should consider obtaining assistance from a professional pest control company to remove the animals. These companies are listed in the yellow pages of your telephone directory.

Going Bats

Far from being pests, all species of bats found in British Columbia are voracious insect predators. Bats eat up to half their weight every night in moths, mosquitoes, beetles, crickets, grasshoppers and flies. A single little brown bat may catch up to 600 insects an hour.

There are 16 species of bats in the province and all are protected under the provincial Wildlife Act. Most species are dark brown with short ears and small bodies about the size of mice. Wingspans range from 20 to 42 centimetres (about 9 to 16 inches). The most common species found in buildings are the little brown bat (Myotis lucifugus) and big brown bat (Eptesicus fuscus), which thrive throughout the province, and the Yuma myotis (Myotis yumanensis), which is found only in the southern part of the province.
Bats enter a building for a variety of reasons, including simply flying in by accident. They may use buildings as a temporary, daytime roost, as a nursery to rear their young or, occasionally, as a hibernation site. Attics are a favourite bat refuge.

Like other mammals, bats can carry fleas, mites and ticks; in rare cases, they contract rabies. Unlike other mammals with rabies, however, they tend to get sick and die before becoming aggressive. According to Agriculture and Agri-Food Canada, which tests about 100 injured, sick or dead bats annually, no one has contracted rabies from a bat in B.C.

Removing Bats from Buildings

When bats get into houses they will usually leave on their own if you close the doors to other rooms, turn off the lights and open outside doors and windows. A sleeping bat can be safely picked up by using a pillowcase as a glove. Reach through the open end of the pillow case and grasp the bat gently in the sewn end. Turn the bag inside out to free the bat outdoors.

The best way to prevent bats from entering the house is to fill cracks under eaves and around pipes, vents, doors and windows. If the holes are big enough for bats to enter (they can get through a dime-sized hole), make sure no bats are roosting inside before you plug the gaps.

If bats are roosting in a remote part of the house, isolated from human activity you may want to consider leaving them undisturbed. They do not gnaw on wood, wires or insulation and will not damage the structure. If the bats are a nuisance, however, there are effective, non-toxic ways to evict them. It is illegal, as well as ineffective, to use pesticides to remove bats. Don't bother trying to chase bats away by playing loud music, installing ultrasonic devices, scattering mothballs or setting up bright lights in an attic. The only sure way to keep bats out of a building is to close up any entrance and exit points while the bats are out hunting. These openings are often small and inconspicuous since bats can squeeze through cracks only 5 mm wide.

To find bat entry and exit points:

• listen for squeaks
• inspect walls for brownish oil stains that rub off their coats as bats squeeze through small cracks
• look for bat droppings (guano) on the ground where they may exit the roost
• watch the suspected entrance at dusk, which is when bats leave the roost to find food

Check areas a metre or more off the ground, near wall and roof joints and under loose chimney flashing. Check for unscreened louvres and air intakes, gaps in the fascia boards, along the eaves and near dormer windows. In the evening, watch for bats flying out of these openings. Between foraging flights, bats may rest under eaves, behind shutters, under loose siding or chimney flashing. If you see bats roosting near your house at night, don't assume they live nearby; they may be kilometres away from their daytime roost.

Close off bat entrance and exit points after dusk during the late summer so that orphaned pups are not left to die while their mothers are stranded outside. Make a one-way escape valve from screening to install over the main exits, which ensures that bats do not re-enter. Use polypropylene bird netting or fly screen to make a large flap over the escape hole. Use duct tape or staples to attach the netting above the exit. The netting should hang loosely and extend about a foot on each side and below the exit point. The bats can slip out from under the mesh, but they can't climb back in. Leave this in place several nights to ensure that no bats remain inside.

Evicting bats is useless unless it is followed by repairs to the building to permanently exclude them. Since bats don't chew their way in, you can block most entrance and exit points using light building materials such as window screen, caulking, duct tape or moulding.

In some cases, it is not possible to evict bats. For example, bats frequently roost under wood shakes on roofs or under cedar siding. In this case, the best option is to learn to live with the bats, especially since they do not damage the building.

Providing a Bat House

If you want to exclude bats from your house, or attract them to your yard for mosquito control, you can provide them with a safe and suitable alternate home in a bat house. These look like bottomless bird houses and are sold at some local nature stores. Instructions for building and setting up a simple bat house are included in the brochure 'Bats' in the Safe and Sensible Pest Control series (see Publications) or from Bat Conservation International, P.O. Box 162603, Austin, TX 78716 (Internet address: http://www.batcon.org/).

More information on bats can be found in:
Nagorsen, D.W., and R.M. Brigham. 1993. Bats of British Columbia. Royal British Columbia Museum & UBC Press, Vancouver, B.C. 164 pp.

Update

Integrated Pest Management Information System

BC Environment's IPM Information System (IPMIS) on the World Wide Web of the Internet continues to grow. A major enhancement to the system was installed in September. This enables users to search for a word or words through all documents in the database, as well as on all words in the title and abstract fields. This means that users are no longer limited to searching just the keywords assigned to the documents.

Over the last several months many complete documents and photographs have been scanned into the database. This includes 100 pest identification fact sheets no longer in print, which were originally published by Agriculture Canada. Fact sheets on forestry pests (including gypsy moth), wildlife and a pamphlet on native beneficial insects have been entered as well as the complete guide for developing IPM plans for coastal landscapes. For users who have systems that handle graphics, the library of colour pictures of pests, pest damage and beneficial insects should provide help in identification. This work is being done with the assistance of funding from Agriculture and Agri-foods Canada and Environment Canada.

Landscape IPM Conferences

With our reduced budget and other pressing projects, BC Environment had not organized a landscape IPM conference as we have in the past two years-but due to popular demand we have reconsidered this decision. Rather than conference format, we are planning to hold 2 workshops in early 1996, addressing particular IPM issues. Environment Canada is again co-sponsoring the workshops. The workshops will be in Vernon on January 22 and 23, 1996 and in Nanaimo, February 22, 1996.

Pest Management Plan Requirement

In 1996, service licencees in the lower mainland and Okanagan regions will be required to submit a pest management plan as a condition of receiving their public land endorsement on their landscape service license. These licensees in the Vancouver Island region have been submitting pest management plans for the last three years.

Pest management plans show how the components of an IPM program (identification, monitoring, use of injury/action thresholds, treatments and evaluation) will be handled for the sites covered by the plan. Descriptions of preventative measures as well as control measures are called for.

To help licensees fill out the plan forms, a guide for completing pest management plans (for coastal landscapes) was developed by a committee of pest management experts from agencies and the private sector. [The complete guide is available on IPMIS-under Search References by Title/Author, enter "Heath" in the author line; or under Search References by Keyword, enter "guide" and press Search].

Over the next few months, BC Environment will assist licensees to develop their plans by giving training workshops and by providing examples of plans from other municipalities.

Liquid Borates for Powderpost Beetles

Of interest to structural pest managers is the recent registration of Tim-bor® for treating wood to control carpenter ants, termites, and wood boring beetles (powderpost beetles, old house borers, longhorn beetles and furniture and deathwatch beetles). This is a water soluble borate salt manufactured by U.S. Borax. Homeowners coping with powderpost beetle infestations will be happy to hear that this least-toxic product is available to commercial pest control companies; until now no pesticides were registered for these pests. Tim-bor is also registered for use in protecting wood against decay fungi. This is an valuable product for use in an IPM program and the label states that "application of Tim-bor to control wood-destroying organisms must be part of an Integrated Pest Management strategy".

The product can be applied as a powder, sprayed or painted on as a liquid solution, or applied in a foam. It can also be injected into wood and into wall voids and other cavities, both as a preventative measure and for treatment of an established infestation. Tim-bor can be used as a crack and crevice treatment for silverfish, cockroaches and ants in food handling areas.

Inquiries about availability of this product should be directed to local suppliers of Commercial structural pesticides or to U.S. Borax, P.O. Box 8090, London, Ontario NG6 2B0.

New Products

BTK for Gardens

After almost two years in Canada without a Domestic product containing Bacillus thuringiensis kurstaki, Safer Ltd. has announced a new BTK product for 1996. 'BTK Biological Insecticide' is for use to control a variety of caterpillars, including tent caterpillars, cabbageworm and tomato hornworm. It is registered for use on vegetables, fruit and shade trees, ornamentals and evergreens.

Available where Safer's products are sold.
Suggested price is $9.99 for 100 ml of concentrate (makes 30 litres of spray).

Flame Vegetation Control

The Red Dragon line of flamers from Flame Engineering, Inc. in Lacrosse, Kansas, is now available through a distributor in B.C. The flamers burn propane and are used to control weeds and other vegetation. The product line ranges from hand-held garden-size torches to commercial size torches; products include a row crop flamer and other flamers that can be mounted on a boom or tractor scoop.

Distributed by:
Kyle Anderson, Coast Valley Marketing Ltd.,
P.O. Box 61554 (Brookswood), Langley, B.C. V3A 8C8
Tel: 604-534-7168 Fax: 604-534-6816

Publications

Prevention and Control of Wildlife Damage

1994. University of Nebraska.

This large 2-volume set of binders is a comprehensive manual covering damage, identification and control of various mammals, birds, reptiles and other animals. Information is detailed and well-illustrated with line drawings. Although the section on armadillos will be of little use to British Columbians, the deer, rodent, birds and other chapters contain valuable and relevant information.

Available as a book @ US$40.00 plus $5.00 shipping or
CD-ROM @US$40.00, plus $3.00 shipping;
both Book and CD-ROM at a discount price of US$60.00 plus $$5.00 shipping.

Send orders to: Wildlife Damage Handbook, 202 Natural Resources Hall, University of Nebraska, Lincoln, NE 68583-0819 Tel: 402-472-2188.

Safe and Sensible Pest Control

1992-1994 By L. Gilkeson
This is a series of brochures developed by BC Environment to encourage the use of safe, practical alternatives to the overuse of pesticide against common pests of home and garden.

Titles available:

Aphids, Bats, Beneficial Insects, Carpenter Ants, Caterpillars, Fleas, Household Insects, Rats and Mice, Lawn and Yard Weeds, Yellowjackets

Videos

IPM: A First Look

1994. Ontario Pesticide Education Program
This video provides an introduction to the principles of integrated pest management. Produced for Ontario growers as part of a series on Best Management Practices. 23 min. Available in English or French. Cost $25.00

Order from:
Ont. Pesticide Education Program, RCAT, Ridgetown, Ontario N0P 2C0
Tel: 519-674-1580 Fax: 519-674-1589

Announcements

Integrated Pest Management in Landscapes: Workshops

BC Environment and Environment Canada are sponsoring two workshops to provide opportunities to exchange information and improve IPM plans.

"Pest Management Planning"

A 2-day workshop on developing IPM plans for landscapes in the interior climate. This is intended to assist service licensees who will be required to submit a pest management plan as a condition of receiving a service license endorsement in the landscape sector. It will be of particular interest to those in the Okanagan and lower mainland regions who will be compiling plans for the first time. The workshop will feature talks as well as discussion groups to give all participants plenty of time to ask questions and work on their own pest management plans.
January 22 & 23, 1996 at the Village Green Hotel, Vernon, B.C.

"Setting Action Thresholds"

A one-day workshop on developing action thresholds and making treatment decisions for landscape pest problems. Presentations during the morning will focus on what treatment thresholds have been developed for turf weeds, aphids and other pests. Part of the day will be spent in working groups to develop and refine treatment thresholds. The intent is to arrive at a set of guidelines for treatment decisions that are workable for local landscapes.
February 22, 1996 in Nanaimo, B.C.For information contact: Good and Co., 2517 Tempe Knoll Dr., North Vancouver, B.C. V7N 4J8 Tel: 604-980-9735 Fax: 604-980-9745

Integrated Vegetation Management Association Conference

January 24 & 25, 1996 at the Stockmans's Hotel, Kamloops, B.C.
"Spring Training: Opening the Toolbox" is the theme of this year's annual general meeting and conference of the IVMA. Topics of presentations include vegetation management in B.C. and the Pacific Northwest, cost/benefit analysis, noxious weed programs, roadside vegetation management programs, herbicide use, manual cutting treatments, use of sheep and myco-herbicides to control vegetation and electrostatic sprayers. A trade show display of vegetation management equipment and services will accompany the event. A conference proceedings will be produced ($25 + G.S.T.)
For information contact: IVMA of B.C., Suite 222, 1077 - 56th St., Delta B.C. V4L 2A2 Tel: 604-943-2733

Forest Insect Management Course

February 1996 in Sault Ste Marie, Ontario.
This course is designed to advance the skills and knowledge of forestry professionals in current techniques and principles for planning, implementing and evaluating Forest Insect Management programs in reference to the broader scope of Integrated Resource Management. Course instructors from across North America will be facilitating a 10-day course through lectures, field trips, practical field exercises and discussion groups. Upon completion of the course, participants will be knowledgeable in:

• the essentials of entomology and principles of forest insect management,
• insect population surveys and damage appraisals and impacts,
• insect management tactics and strategies,
• insecticide application technology,
• forest insect management efficacy and impact from a biological and economic perspective, and
• current advances and trends in organizing an insect pest management program.

For information contact:
Eileen Harvey,
Canadian Forest Service,
Forest Pest Management Institute,
1219 Queen Street East, Sault Ste Marie, Ontario P6A 5M7
Tel: 705-757-5740 ext 2251 Fax: 705-759-5728
E-Mail: eharvey@pmoeafpm.fpmi.forestry.ca