Conservation Officer Service

A Gardener’s Guide to Preventing Deer and Elk Damage

Part of the appeal of living in rural or semi-rural British Columbia is the ability to watch wildlife in your own back yard. Deer, elk and bighorn sheep (ungulates) are especially fascinating to observe, but many homeowners are dismayed to discover that ungulates can be very destructive to gardens.In some areas the damage can be seasonal, peaking in the winter when food sources for ungulates are lowest. Other areas where may experience problems year-round. Still others face a peak of damage during summer when garden crops are at their best. Drought, wildfires, livestock grazing and other habitat-altering events also play a role because they affect food sources. Homeowners frequently ask the BC Wildlife Branch how to minimize landscape and garden damage caused by ungulates. This paper details six methods:

• Use of landscape plants that ungulates don’t seem to like;
• Use of landscape plants which ungulates can’t reach;
• Application of commercial deer repellents;
• Use of motion detecting sound, light or water scare mechanisms;
• Construction of deer, sheep and elk-proof fencing;
• Use of browse "barriers".

All of the techniques are considered harmless to deer and other wild and domestic animals. The majority of the information available is related to deer, but is considered useful for elk and bighorn sheep as well. If you live in an area frequented by ungulates and wish to minimize or prevent damage to your ornamental plants or fruit and vegetable crops, it is useful to plan ahead. Careful consideration should be given to grouping crops so that they can be fenced easily and inconspicuously. Look at the long-term development of a garden, which is not only largely inedible to ungulates, but is also physically unavailable to them because of size or shape. Damage occurs not only because of feeding, but also because of antler rubbing, herd stampeding or from plant pushing.

‘Deer Resistant’ Plants

Deer are attracted to many popular garden and landscape plants but avoid others. The following list of deer-resistant plants should be considered a guide rather than the final word. Elk and sheep are likely to avoid similar plants. Certain plants may not suffer deer damage in some gardens and landscapes, yet might be completely destroyed in others. This is due in part to the availability of natural food sources and the taste preferences of individual deer or elk. If there is a shortage of natural deer browse, deer resistant plants may suffer. In addition, during winter homes often occupy the best habitat, where snow depths are least and the deer and elk move in because of deep snow nearby. Since they are often starving in winter, they put additional pressure on plants they might not touch in summer. Some of the plants listed are, in addition to being deer-resistant, considered noxious weeds.

For example, Purple loosestrife is a pervasive grower in wet sites and can become a significant problem because of its invasive nature and tendency to escape. Native plants are better adapted to the local climate than their exotic counterparts, and should be considered first in landscape planning.

Some of the plants that are desirable as food items for deer are capable of recovering rapidly from damage though resprouting while others are incapable of resprouting or regaining their original form. Particular care should be taken to avoid the use of certain the plants that cannot regain their intended form in applications such as hedges. Popular decorative cedar hedges, for example, are very poor at regaining their original form once browsed. Both native and introduced plants are listed in this booklet. Always consult a local nursery to select species that best fit your needs and your local climate.

The Ministry of Environment, Wildlife Branch encourages use of native plant species where feasible. For example spruce and western red cedar are much more resistant to browse damage than emerald or pyramid cedars.

References:

• "The Standard Encyclopedia of Horticulture. "Bailey, L.H. 1949. The MacMillan Company, New York, 3 vols. II, pg. 1786.
• "A New List of Deer Resistant Plants for the Garden." Pacific Horticulture, November 1990. Deer-Resistant Plants for Ornamental Use" University of California Cooperative Extension. 1980. Leaflet 2167.
• "Sunset Western Garden Book." Fifth Edition, Lane Publishing Company, California.

Resistance of woody and herbaceous plants to deer and elk damage

This list is included only as a guideline and was developed from a variety of sources which might not all be equally reliable. Note that no plant is completely "deer or elk-proof", particularly when deer or elk densities are high.

Woody Ornamental Plants Rarely Damaged by Deer and Elk

Herbaceous Plants Rarely Damaged by Deer and Elk

Woody Ornamental Plants Seldom Severely Damaged by Deer and Elk

Woody Ornamental Plants Occasionally Severely Damaged by Deer and Elk

Herbaceous Plants Occasionally Damaged by Deer and Elk

Annuals and biennials

Pansy
Sunflower

Perennials

Woody Ornamental Plants Frequently Severely Damaged by Deer and Elk

Herbaceous Plants Frequently Damaged by Deer and Elk

Annuals and biennials

Perennials

Plants out of Reach of Browsing Ungulates

Most garden plants are low growing and are therefore available to browsing ungulates. However, the development of new commercial fruit varieties, which are much smaller trees than were available 30 years ago, has increased the problem. Plant tree varieties that will rapidly grow out of reach of deer and elk. Prune trees to a form that eliminates their browse damage and you will greatly reduce the degree of damage experienced. Where deer and bighorn sheep are the main problem the trees need only be pruned up to about 1.5 meters above the ground. Elk require higher pruning and bigger trees to prevent damage as they are taller and also have a habit of pushing over small trees to get at upper limbs. It may be necessary to go to 2 metes to prevent elk damage.Protect the trees until they are out of reach through fencing or barriers such as netting or burlap. Fine netting or woven monofilament netting may also be suitable. These are available in long, wide pieces that can be draped over entire rows. Posts around small trees are useful in preventing breakage when the trees are still small and protect trees from antler rubbing in autumn. Very young trees can be protected with mesh net tubes that are available commercially.An alternative to large apple trees may be to use the new trellis varieties with close tree spacing. These are grown like a hedge and can be protected in winter with fencing tied along each side to an appropriate height for deer or elk.

Deer Repellents

Various types of devices and chemicals have been used to repel deer including scare devices, over-the-counter repellent sprays and powder, and home remedies. Scare devices such as exploders, radios, lights, and even a dog on a leash have short-term limited effectiveness at best. Home remedies such as hanging bags of hair, soap, rotten eggs or animal urine are not trustworthy, long-term repellents. Over-the-counter repellents have been the most successful deterrent for non-commercial users experiencing light to moderate damage. However, repellents must be applied frequently and vigilantly prior to and during the period of anticipated damage in order to be effective. For example, repellents should be applied to plants prior to planting and reapplied during the growing season. ‘Deer Away,’ made from putrescent whole egg solids have been the most widely used and effective repellent spray. Other repellents available are:

Alarms and Scare mechanisms

A variety of equipment is coming onto the market based on motion detectors that activate lights, make sonic or ultrasonic noises or spray water. Most are sold as successful deterrents for small animals such as dogs, cats, raccoons, and occasionally deer. These mechanisms respond immediately to the presence of animals and the animals are less likely to become used to the noise or light. They are typically effective over relatively small areas because of the limited range of most motion detectors (10 meters). Devices such as these are most likely to be successful in situations where the deer or elk have other food alternatives easily available. When they are starving in winter they will endure much more disturbance than in summer when food is abundant. Commercial scare devices are available through Home Controls Inc, or Smart Home, both of which have excellent on line sales catalogues on the Internet. Paper catalogues are available from both as well:

Margo Supplies Ltd.
Box 5400
High River, Ab. T1V 1M5
(403) 652-1932
www.margosupplies.com

Smarthome.com, Inc,
17171 Daimler Ave,
Irvine, CA, 92614-5508,
1-800-762-7846 or 1-800-871-5719
www.smarthome.com

Home Controls, Inc.
Suite 3300 - 7626 Miramar Road,
San Diego, CA, 92126, US
1-800-226-8765 (orders only)
www.homecontrols.com

It may also be possible to create your own scare devices through the use of motion detector switches or outdoor lights. These easily available devices can be attached to a variety of noisemakers, lights or even to sprinklers with a little ingenuity. For example, a motion detector switch could be mounted where it will activate when deer are present and could activate an existing automatic sprinkler system. Care must always be taken to insure that a qualified electrician installs such devices. Commercial scare devices such as propane exploder cannons are also available. These devices make very loud bangs at regular intervals, which drive away deer, elk and birds. They are only suitable for large areas as they make much too much noise for a residential neighborhood.

Fencing applications

For nurseries, orchards, pastures, and large gardens, fencing is the often the only way to prevent damage from animals. Many of the fencing options discussed on the following pages also work well for small gardens because they are easy to build and very cost-effective. The following fencing designs are the primary methods being used by professional game managers and many US State and federal agencies to control damage from both livestock and wild animals. Basic design, cost of materials/foot (not including labor), cost per foot/year, and life expectancy of fencing can be found by contacting:

Margo Supplies Ltd.
Box 5400
High River, Ab. T1V 1M5
(403) 652-1932
www.margosupplies.com

or your local fencing or garden supply shop.

Barriers

Ungulates can be discouraged from causing winter damage to plants through the use of simple barriers such as burlap material or sacking. A wide variety of techniques can be employed to reduce or eliminate damage by placing a barrier around individual plants or groups of plants. Similar techniques would work in summer but generally are not useful because they are unappealing visually. Netting applications may be useful in some situations. Wrap each plant you think may be browsed with burlap or other inexpensive cloth or netting from near the ground to the maximum height you expect to be browsed. Deer can reach to about 1.3 meters, while elk can reach to as much as 2.0 meters. String or rope can also be used on some trees in a similar fashion to that used to protect from snow damage. The tight form of the wrapped tree and the solid surface created makes it difficult for ungulates to browse. Netting of various types can be used to protect crops. Fine mesh nets, particularly the new woven monofilament nets designed to keep birds off of commercial fruit farms, may be particularly useful as they come in long and wide sections which can cover extensive areas or large trees. Entire cherry tree rows are covered in some commercial applications. These are useful in both summer and winter applications since the plants growth and crop development is not delayed. Some may be suitable for nightly application and removal in special circumstances. Chicken wire or stucco wire with a small enough mesh size (< 4 cm) to prevent reaching through the fence can also be effective in preventing damage in some situations. Short pieces can be used to wrap individual plants in a similar fashion to burlap. Longer pieces can be attached to either side of hedges creating a low barrier on either side of the plants for the winter months. These may be tied directly to the plants or may be propped in place using temporary fence posts such as rebar or wooden stakes.

Summary

Many options exist to limit or prevent garden damage by deer and elk. Plan ahead to limit the attractiveness of your garden during all seasons and you will drastically reduce problems and costs. Vegetable gardens provide a significant value to many homes and the cost of fencing may be low in the long term, relative to the loss of crops and the disappointment of all the work that is wasted. Fences last a long time if properly constructed and with good planning can be an acceptable part of the landscape plan. In winter take the time to protect vulnerable plants. An hour of work putting up burlap on vulnerable shrubs can prevent permanent damage and avoid the need for expensive replacement plants that take years to re-grow. Acknowledgements Significant parts of this paper have been taken from "A gardener’s guide to preventing deer damage", Coey, Bob, and Kenneth Mayer, California Department of Fish and Game. In addition the plant list was supplemented from a list provided by Paul Curtis, Cornell University. Their assistance is gratefully acknowledged.