Deer Browsing Damage: Identification, Prevention & Treatment

Deer browsing in Maryland causes thousands of dollars of damage to residential and commercial landscapes, as well as home vegetable gardens and commercial crops. While summertime deer browsing is bad enough, winter can be worse. As winter wears on and food becomes scarce, you may find deer (and their damage) where you haven’t before.

In this article, we explain:

• why deer are such a problem in Howard County,
• the signs that deer have been dining in your landscape and when to look for deer browsing damage,
• how to keep deer away, including deer-resistant plants appropriate for Maryland properties, deer barriers, and repellents, and
• how (and if) you can help deer-damaged plants recover.

Deer in Howard County, Maryland

If it seems like deer are everywhere, you’re not imagining things; there are lots of deer around. Deer population levels have traditionally been kept in check by their predators. When those predators – such as bobcats, wolves, and coyotes – disappear, deer populations immediately rise.

Human development patterns, especially suburban development or “sprawl,” create ideal situations for deer to thrive. The big predators lose their roaming habitat when development clears forests and fragments the remaining areas. As a result, deer increase in number and expand their range.

Howard County alone has more than 10,000 deer, which is more than twice the number considered “sustainable”. Overpopulation leads to food shortages and causes deer to wander into suburban, and even urban, areas.

While deer may remain frightened of humans, they will make themselves at home in neighborhoods and gardens, as well as landscaped commercial buildings and campuses. Deer will cross busy roads and highways, not always successfully, but they will go to great lengths to find food.

Identifying Deer Browsing Damage

There are several signs that deer have decided your property is the perfect all-you-can-eat buffet. Here are the things to look for.

Droppings

The first sign that you have had deer visiting your landscape are scattered droppings. Deer poop is pellet-like and looks like rabbit poop, except larger and in greater quantities. If you have hardscape areas adjacent to plants that deer like, you’ll probably find deer droppings on the concrete or pavers.

Signs of Deer Browsing

Deer browsing damage can be neat or ragged, depending on the plant and how strongly the deer pull at the leaves and flowers.

Deer are browsers; they eat the flowers, leaves, and shoots of perennial and woody plants that are higher off the ground. In contrast, cows and sheep graze on low-growing grasses and forbs. As a result, you’ll typically see deer damage at eye-level – and even above, if the deer stood on its hind legs to reach a particularly tasty leaf.

Deer browsing damage is fairly obvious. Look for:

• leaves partially or completely eaten,
• green shoots on trees chewed off,
• twigs ripped off branches, and
• empty spaces on flowering plants where flowers and flower buds used to be.

When to Look for Deer Browsing Damage

You’re more likely to see deer browsing on different plants at different times of the year. The amount they eat, and the severity of the damage, will also vary with the seasons. Here’s where to look for deer damage throughout the year:

• January to March – Coniferous shrub and tree needles and branches, deciduous bark and dry leaves, acorns and other nuts, winter fruits such as rose hips, sumac, and poison ivy (4 to 5 lbs/day)
• April to June – Herbaceous plants and grasses, buds and shoots on all types of shrubs and trees (7 to 10 lbs/day)
• July & August – Herbaceous vegetation, young leaves, new growth of shrubs and trees, anything growing in home gardens
• September to December – Fruits and nuts (acorns make up to 50% of diet), bramble leaves, mushrooms, whatever is left in your garden

While there are plants that deer don’t like when a deer is hungry enough, it will sample almost everything.

How to Prevent Deer Damage

If you want to keep your landscape from looking ragged or patchy from deer browsing damage, we’ve got information for you about the measures you can take – and when it may be time to acknowledge that it’s a losing battle.

Option #1: Use Plants That Deer Don’t Like

It often feels like deer eat everything. For example, if you grow roses, or wisteria, or clematis, be prepared to lose flowers and leaves to browsing deer. The same goes for annuals and bedding plants such as petunias and pansies. They’re juicy, tender, and deer will head right for them!

But there are plants that are naturally less appealing to deer, and we encourage you to start your deer deterrent efforts there. Removing “deer candy” from your landscape and replacing it with deer-resistant plants can:

• save you money,
• provide much-needed habitat for pollinators and bees, and
• reduce maintenance costs.

Many plant species that don’t appeal to deer are longer-lived, native, and provide multi-season interest. An experienced landscape designer will know which plant species to select and how to combine them to make a beautiful design that deer won’t decimate.

Here are some of the familiar and readily available plant species that deer are less interested in:

Deer-Resistant Trees

(Plants in BOLD font are native to Maryland)

• Allegheny Serviceberry (Amelanchier laevis)
• American Beach (Fagus grandifolia
• American Holly (Ilex opaca)
• Bald Cypress (Taxodium distichum)
• Black Gum (Nyssa sylvatica)
• Chinese Paper Birch (Betula albo sinensis)
• Colorado Blue Spruce (Picea pungens glauca)
• Douglas Fir (Pseudotsuga menziesii)
• Downy Serviceberry (Amelanchier arborea)
• Eastern Red Cedar (Juniperus virginica)
• Flowering Dogwood (Cornus florida)
• Gingko (Gingko biloba)
• Heritage Birch (Betula nigra “Heritage”)
• Honey Locust (Gleditsia triacanthos)
• Japanese Cedar (Cryptomeria japonica)
• Japanese Falsecypress
• Kousa Dogwood (Cornus kousa)
• Paw-Paw (Asimina triloba)
• Pitch Pine (Pinus rigida)
• Sassafras (Sassafras albidum)
• Sweetbay Magnolia (Magnolia virginica)
• Sweetgum (Liquidambar styriciflua)
• Sycamore (Platanus occidentalis)

Deer-Resistant Shrubs

(Plants in BOLD font are native to Maryland)

• American beautyberry (Callicarpa americana)
• American elderberry (Sambucus canadensis)
• Andromeda (Pieris japonica)
• Arrowwood (Virburnum dentatum)
• Beautybush (Kolkwitzia amabilis)
• Blackhaw (Viburnum prunifolium)
• Bluebeard (Caryopteris x clandonensis)
• Button Bush (Cephalanthus occidentalis)
• Chinese Holly (Ilex cornuta)
• Chinese Juniper (Juniperus chinensis)
• Common Lilac (Syringa vulgaris)
• Deutzia (Deutzia gracilis)
• Dwarf Sweet Box (Sarcoccoca hookeriana var. humilis)
• Fetterbush  (Eubotrys racemosa​)
• Fothergila (Fothergilla gardenia)
• Inkberry (Ilex glabra)
• Japanese Plum Yew (Cephalotaxus harringtonia var. horeana)
• Lilac (Syringa vulgaris)
• Mountain laurel (Kalmia latifolia)
• Mugo Pine (Pinus mugo)
• Red Chokeberry (Aronia arbutifolia)
• Red Osier Dogwood (Cornus sericea)
• Spicebush (Lindera benzoin)
• Sweet Pepperbush (Clethra alnifolia}
• Wax Myrtle (Morella cerifera)
• Winterberry Holly (Ilex verticillata)

Deer-Resistant Flowers & Perennials

(Plants in BOLD font are native to Maryland

• Allegheny Spurge (Pachysandra procumbens)
• Astilbe (Astilbesp)
• Black Cohosh(Actaea racemosa)
• Black-eyed Susan(Rudbeckia hirta)
• Bleeding Heart(Dicentra exemia) and the non-native (Dicentra spectabilis)
• Butterfly Weed(Asclepias tuberosa)
• Christmas Fern(Polystichum acrosticoides)
• Columbine(Aquilegia canadensis)
• Common Dill (Anethum graveolens)
• Culver’s Root (Veronicastrum virginicum)
• Euphorbia (Euphorbia spp.); some species are native
• Flowering Tobacco (Nicotiana spp.)
• Foam Flower(Tiarella cordifolia)
• Foxglove(Digitalis spp.)
• Golden Ragwort(Packera aurea)
• Hayscented Fern(Dennstaedtia punctilobula)
• Hyacinth (Hyacinthus orientalis)
• Jack-in-the-Pulpit(Arisaema triphylum)
• Lady Fern(Athryrium felix-femina)
• Lavender(Lavandula spp.)
• Marigold(Tagetes spp.)
• Monkshood (Aconitum spp.); some native species
• Nasturtium (Tropaeolum majus)
• Ostrich Fern(Matteuccia struthiopteris)
• Purple Coneflower (Echinacea purpurea)
• Royal Fern(Osmunda regalis var. spectabilis)
• Rue Anemone(Thalictrum​ thalictroides)
• Sage (Salvia spp.)
• Snapdragon(Antirrhinum majus)
• Swamp Milkweed(Asclepias incarnata)
• Threadleaf Coreopsis(Coreopsis verticillata)
• Thyme(Thymus spp.)
• Toadflax(Linaria vulgaris)
• White Wood Aster (Eurybia divaricata)
• Wild Ginger (Asarum canadense)
• Wood Fern(Dryopteris marginalis)
• Yarrow(Achillea millefolium)
• Yucca(Yucca spp.)

Ornamental Grasses

(Plants in BOLD font are native to Maryland)

• Bluestems (Andropogon spp.)
• Canada Wildrye (Elymus canadensis)
• Indiangrass (Sorghastrum nutans)
• Little Bluestem (Schizachyrium scoparium)
• Pennsylvania Sedge (Carex pennsylvanicum)
• Purple Lovegrass (Eragrostis spectabilis)
• Sea Oats (Chasmanthium latifolium)
• Soft Rush (Juncus effusus)​
• Switchgrass (Panicum virgatum)

List provided by the Maryland Department of Natural Resources 

If you’d rather use native plants, the University of Maryland has a list of native plants that deer don’t love.

The bottom line is that deer don’t like aromatic or oily plants. That’s why lavender, rosemary, thyme, and bee balm make good flowering-plant choices for sunny spots, as do marigolds.

Deer also avoid bitter or fibrous plants, so yuccas are good choices for spiky foliage and stalks of blooms, as are euphorbias and tall ornamental grasses.

When choosing deer-resistant plants, be sure to choose only plants that are not invasive in Maryland, such as barberry (deer don’t like it but it spreads aggressively here). Check the Maryland Department of Natural Resources for a list of invasive plants to avoid.

We say deer are less interested in the species listed above because it’s nearly impossible to guarantee a deer won’t sample a plant. The overpopulation of deer means there’s automatically a shortage of food for them. Deer will eat almost anything if they’re hungry enough, and that includes “deer-proof” plant species. In winter, hungry deer will also gnaw bark off trees.

Option #2: Keep Deer Away From Plants

To prevent deer from getting to your plants in the first place, you’ll need a barrier they can’t or won’t cross, or a repellant.

Deer Repellent Sprays

The first thing people often use is a repellent, as they’re readily available and easy to apply. There are many brands on the market; we’ve found success with Deer Scram, which we use with our commercial landscape maintenance clients.

Many repellent sprays use odors and tastes such as sulfur, garlic, or peppermint to keep deer from eating foliage. Always choose a non-toxic spray and avoid any that have nicotine or ammonia in them. And please don’t use mothballs – these toxic balls can damage your plants and your soil.

Repellents need to be reapplied periodically, especially when plants are growing quickly and after rain or being doused with irrigation sprinklers. Deer can also get used to repellents. If you notice that your deer repellent doesn’t seem as effective as it once was, it’s time to switch it up for something with different active ingredients.

DIY Deer Repellents

DIY repellent options that are regularly recommended include hanging bars of strongly-scented soap or bunches of human hair from branches or installing motion sensors that send out streams of water to frighten deer away.

Before you invest in any deterrents, do your own investigation into their effectiveness. And before you install motion sensors, remember how adaptable deer are and how quickly they can lose their fear if they are not injured by a deterrent.

Install Deer Fencing

A good deer fence is usually eight feet (8’) high; bounding deer can easily leap over anything less than 7.5’ high.

Deer fencing and fence panels of that scale can be expensive, but there are options. One of the most common materials for fence panels is flexible plastic “deer” fencing, which is inexpensive and will last from five to 20 years. It’s functional but not particularly attractive.

A sturdier and more refined fence can use panels of rigid, welded wire mesh. When coated in black polypropylene, it almost fades into the landscape. This type of fencing, combined with screening shrubs and trees that deer don’t like, is the best way to keep your landscape free from deer damage while still looking well-designed and healthy.

NOTE: If you install a new fence to keep deer out, tie some flashing material to the fence at deer-eye height so that deer don’t run into it. While deer may be your sworn enemy, you don’t want to injure them for no reason.

Wrap Plants in Burlap

Winter plant wraps, such as burlap, will also provide your evergreens with additional winter protection from deer browsing. Be sure to wrap your shrubs and young trees up to the “browse line” (about 5’ or more above the ground).

But, unless you’re Christo, you can’t keep things wrapped forever. Take advantage of the protection burlap offers, but make a longer-term plan to keep deer away.

How to Help Deer-Damaged Shrubs & Trees Recover

Healthy, well-maintained plants can survive and recover from a surprising amount of deer damage. However, according to the Natural Resources Conservation Service, excessive deer predation can:

• create double or multiple leaders,
• increase susceptibility to frost damage,
• weakens branching,
• create poor form,
• provide a path for disease or insect infestation,
• suppress seedling height, and
• increase plant mortality.

If the damage is extensive enough, such as when a tree has been girdled (bark removed in a ring around the entire tree trunk), you may want to replace your plants instead of trying to save them.

Clean Up Wounds

Deer tear at their food, rather than making neat cuts with their teeth. This leaves ragged wounds that are susceptible to further damage by pathogens and insect pests. Clean up injured stems by using sharp pruners to cut stems back to the closest healthy new growth.

Restore Shape

Corrective pruning can be used to restore at least some semblance of a deer-damaged tree or shrub’s natural form. Severely deformed plants may not be worth saving.

H4Give Damaged Plants Some TLC

Damaged plants will also benefit from consistent and sufficient irrigation throughout the growing season, as well as supplemental fertilization (if needed – we recommend doing a soil test first to see which, if any, nutrients are lacking in your soil).

In Summary

It may not be the most inexpensive method, but the combination of a secure fence, repellants that work, and unappealing plant species is the best defense against deer damage to your landscape. In the end, it’s an excellent investment in the health and beauty of any landscape in “deer territory”.

Replacing otherwise healthy plants that are frequently damaged by deer is hard to do. But the option of maintaining a landscape that will always struggle to grow while being defoliated, damaged, or stunted from deer browsing is not satisfying or economical. Deer will continue to roam our urban and suburban landscapes and continue to eat our treasured plants, shrubs, and trees. It’s up to us to make some hard decisions and change the way we design our environments.