Deer on Plants

Symptoms

The signs of deer fall into three groups: damage to foliage, marks on the ground, and harm to trees. Browsed leaves and tender stems have ragged, torn edges. You may also find trampled plants and shredded or ragged foliage, buds, or terminals. On the foliage, a distinct browse line often shows at around 4 to 5 feet (1.2 to 1.5 m) high.

Check the ground as well. Piles of small jellybean-shaped droppings are one sign. Hoofprints are split and measure two to three inches (5 to 8 cm).

Young trees can show stunted or misshapen growth. Browsing on fruit buds can lower fruit production. Girdled trunks or branches can result from deer rubbing against them with their antlers. Antler rubbing can also leave broken limbs and girdling of the trunk.

Stunted or misshapen growth is listed for young trees, while girdling and broken limbs come from antler rubbing. Trampled plants are listed alongside the shredded foliage, so flattened plants can be a sign too.

Causes

Deer come into a garden when food elsewhere runs short. Natural food sources may be out of season or otherwise unavailable. Food scarcity during drought years is another cause. Winter food scarcity is a third.

Irrigated landscape plantings increase the food available to deer. In other words, watered landscape plantings add to the food on offer. Suburban gardens also carry a reduced risk of predation. Nearby woodland or posted or refuge areas can give deer daytime cover. Daytime cover and low predation risk both describe the surroundings, not the plants.

Small or young trees are more susceptible. Buck antler rubbing is a separate cause of damage to trunks and branches.

The causes fall into two groups: those about food and those about the setting. Drought years and winter both appear among the causes of food scarcity. Several of these causes are tied to a time of year or a dry spell.

Diagnosis

No cited source here names a look-alike problem, so this section compares deer damage with a general care fault. Deer damage is marked by ragged, torn edges on browsed leaves and tender stems.

Look for signs that come with the animal itself, such as jellybean-shaped droppings and split hoofprints that measure two to three inches (5 to 8 cm). A distinct browse line at around 4 to 5 feet (1.2 to 1.5 m) is another marker of deer. Trunk damage helps too, because girdled trunks or branches and broken limbs come from antler rubbing.

Stunted or misshapen growth on young trees and lowered fruit production from browsing on fruit buds are listed as deer symptoms as well. Together, torn foliage, droppings, split hoofprints and a browse line make up the pattern listed for deer.

Compare your setting with the causes: nearby woodland or refuge areas, irrigated plantings, drought years and winter all appear on the list. The listed causes are about food, predation risk, cover nearby and antler rubbing.

Treatments

A properly built and maintained fence 7 to 8 feet (2.1 to 2.4 m) high is the most effective control method. Build it carefully, since deer are more likely to crawl under or through a fence than jump over it. For individual plants, use wire or plastic plant protectors. Temporary polypropylene fencing can protect young plants while they establish. The Penn State low-cost five-wire electric fence design is another option around a planting. Keep a mowed strip 6 to 8 feet (1.8 to 2.4 m) wide along the fence perimeter.

You can choose and plant less palatable, deer-resistant landscape species, testing a few in pots before planting in quantity. Motion-activated sprinklers or frightening devices may work for a period of time in some situations. Encouraging hunting in the area can help manage local deer density.

Repellents containing fermented egg compounds are more effective than other repellent types. Contact repellents with putrescent egg solids or capsaicin (hot pepper sauce) go on foliage at the first sign of damage. Area repellents such as tankage, ammonium soaps, bone tar oil, blood meal, or human hair go around plantings.

Thiram is applied as a contact repellent directly to plants. Denatonium saccharide is an approved deer repellent that is less effective and only protects dormant growth. For any product, the label is the legal instruction and must be followed for the crop and site being treated.

Prevention

Pressure from deer is tied to conditions: food out of season, drought years and winter scarcity are all listed causes. A fence 7 to 8 feet (2.1 to 2.4 m) high, properly built and maintained, is the most effective control method. Deer are more likely to crawl under or through a fence than jump over it. Keep a mowed strip 6 to 8 feet (1.8 to 2.4 m) wide along the fence perimeter.

Small or young trees are more susceptible. Wire or plastic plant protectors can shield individual plants. Plant less palatable, deer-resistant landscape species, and test a few in pots before planting in quantity. Temporary polypropylene fencing can protect young plants while they establish.

Local hunting can help manage deer density in the area. Nearby woodland or refuge areas give deer daytime cover, and irrigated plantings increase the food available.

Plants most often affected

No plant page in this build records this problem yet.