Trees, Shrubs and Vines of Wildlife Value- a companion to the chapter in "Wildlife and Your Land", a Wisconsin DNR publication

Note: Click on common name for link to images from the Cofrin Center for Biodiversity at UW-Green Bay. Click on (G) to see Google image

s for a particular species.

VINES

Virginia creeper +(G) - good wildlife value, but can be a problem in grasslands - spreads aggressively.

Wild grape + (G) - good wildlife value, but can be very aggressive and cover and shade out other vegetation. Also a problem in grasslands.

SHRUBS

Common blackberry +(G) and black raspberry + (G) - highly preferred, good escape cover, but can be very aggressive in grasslands.

Red osier dogwood + (G) , gray dogwood + (G) - both of these species provide excellent food and cover, but can spread in wetlands or grasslands and may need to be controlled by prescribed burning.

American hazelnut + (G) - (south of Tension Zone) and beaked hazelnut + (G) (north of Tension Zone) - Ruffed Grouse like the catkins - I've seen lots of grouse in hazelnut at Kinni State Park.

Highbush cranberry + (G) - fruits not very palatable, so a good emergency food that is available when more preferred foods are gone late in winter.

Nannyberry + (G) - excellent winter food source, grow best in shade of woodland borders but I've grown them in full sun.

Staghorn sumac + (G) , smooth sumac + (G) , fragrant sumac + (G) - Sumac is beneficial for a variety of wildlife; however, smooth and staghorn sumacs grow rapidly in spreading, circular colonies, and spread as well by seed; it can be difficult to control once established. You don't have to be able to distinguish between these three for the quiz, just be able to recognize any of them as a "sumac".

Wild rose + (G) - Rosehips are eaten as emergency winter food by ringnecked pheasants, sharp-tailed grouse and prairie chickens. Deer, cottontail rabbits and small mammals browse the twigs. Do not plant the alien multiflora rose (Rosa multiflora + (G) ). This invasive non-native is illegal to plant under the Wisconsin nuisance weed law because it is very aggressive and spreads rapidly.

Wild plum + (G) - Wild plum grows in dense thickets along sunny roadsides and fencerows, often amidst other trees or shrubs. Wild plums provide excellent nesting habitat for many songbirds and cover for small mammals. Foxes and other mammals eat the fruit and deer browse on the leaves and twigs. The fruit also makes excellent jelly and jam (it is really good!)

Serviceberry or Juneberry + (G) Serviceberry bears fruit in late June, making it one of the earliest summer berries. Excellent for a variety of birds and mammals. The fruit tastes and can be used much like blueberries. Many species in this genus.

DECIDUOUS TREES

Key to the trees of Wisconsin - UW-Green Bay website.

Beech + (G) - grow near Lake Michigan where the lake creates the cool, moist environment that these trees prefer. They grow best on good quality, rich soils. While beeches may be planted farther inland, hard winter freezes may kill them. Nuts are an excellent food source. The nut crop is large about every 2 or 3 years.

Black walnut + (G) - grow mainly in southern hardwood forests on deep, well-drained, silty loam soils, and often reach a height of 100 feet. Despite the thick and coarse bark, the black walnut makes a great cavity and den tree for a variety of animals. They’re also highly valued for their wood.

Butternut + (G) - grows on rich soils with other hardwoods in southern Wisconsin. Woodpeckers, wild turkeys, and fox and gray squirrels crack open the tough shells to get at the tasty butternuts inside. Wood ducks, finches and songbirds eat the buds. These trees are very susceptible to Butternut canker disease, a very serious problem.

Big-Toothed Aspen + (G) , Quaking Aspen + (G) - grow rapidly on average to dry soils statewide, though they are more common in the north. Don't confuse these species with cottonwood, which is a much larger tree in the same genus (note the more triangular leaves of cottonwood). Aspen, also called poplar or popple, grows up to 60 feet and reaches maturity at 50 years, after which it rapidly declines and can make a good cavity tree long before other hardwood trees. Aspen is the favorite food of many animals, especially deer, grouse and beavers. To regenerate aspen, clearcut an existing aspen stand—the trees are shade intolerant and regenerate very well by root sprouts. Aspen are shortlived and their soft, punky wood is used by woodpeckers and chickadees for nest cavities. Do not plant aspen near prairies or savanna areas; the trees will spread and out-compete prairie vegetation. Excessive spread of aspen is best controlled by girdling.

Basswood + (G) - Basswood makes a great den tree for wildlife. Squirrels, chipmunks and rabbits love the nutlets. Rabbits and deer eat the leaves and tender twigs. It is part of the maple-basswood climax community.

Yellow Birch + (G) , Paper Birch + (G) , River Birch + (G) - All birches provide good browse for whitetailed deer and moose. The shreddy bark provides nest material for vireos, warblers and tanagers. Ruffed and sharp-tailed grouse feed on the catkins, buds and seeds, while the pine siskin and common redpoll consume the seeds. Beavers, snowshoe hares and porcupines prefer to eat leaves and stems. Chickadees, titmice and several woodpeckers use dead or dying birch for nesting cavities.

Boxelder + (G) - Boxelder's fast-growing, weak wood frequently forms cavities that make good dens for birds and mammals. Although boxelder has some good wildlife attracting qualities because it produces very large seed crops, the DNR doesn’t recommend planting this weedy, invasive tree. Chances are it will occur naturally.

CONIFERS

Balsam Fir + (G) - Balsam fir stands make good cover for many birds and small mammals. White-tailed deer, moose and spruce grouse also browse on the twigs of balsam fir.

Northern White Cedar + (G) or “Arbor Vitae” - White cedar swamps are critical overwinter habitat for deer in northern Wisconsin. Because white cedar is a favorite browse of deer, these mammals are preventing natural regeneration in many areas.

Eastern Red Cedar + (G) - If planted as an ornamental, be aware that red cedar is an alternate host for cedar rust, which damages crabapple trees. Many ornamental varieties of cedar exist and should be avoided. Be aware that cedars can shade out prairie vegetation and any ground flora in yards, and will spread rapidly. They should be aggressively controlled in native prairie areas by cutting.

Hemlock + (G) - Hemlock is a highly valued wildlife food. Deer prefer hemlock and will heavily browse the branches and tips, seriously limiting the trees' growth and reproduction, especially of those trees located near deer wintering yards.

Jack Pine + (G) - requires fire to release seeds from the tightly closed cones. Jack pine makes great cover for songbirds, deer, rabbits and small mammals. The red squirrel, pine siskin and purple finch eat the seeds once released by fire.

White Pine + (G) - White pine is an important component of hill and rocky bluff pine forests in south central and southwest Wisconsin. Seeds are eaten by a variety of birds and mammals. Young pine stands provide good thermal cover during winter for deer and birds. Large white pines provide roosts for wild turkeys and ruffed grouse, and nesting sites for ospreys and eagles.

Red Pine + (G) - Because of its general freedom from disease and insect attacks, red pine is frequently planted in pine plantations. Such plantations have little value to wildlife because of a lack of understory growth. Nevertheless, as a small conifer, these trees can provide thermal shelter to wildlife in winter.

White Spruce + (G) , Black Spruce + (G) White spruce grows on moist welldrained soils in northern forests; black spruce grows only in wet northern forests, including bogs. Both spruces have dense branches, which they retain low to the ground. This provides some of the best winter cover for songbirds and rabbits, and nesting cover for songbirds in spring. Spruce grouse and snowshoe hares feed heavily on the needles. As a last resort in hard winters, deer will browse on spruce twigs and needles (a "starvation" food).

Tamarack + (G) (American larch) Larix laricina Zone 3 to 5 Fall food Tamarack grows in northern swamps and in scattered southern lowlands that have wet soils. It will not do well if planted on upland sites. It is Wisconsin's only conifer that sheds its needles each fall, Songbirds eat the seeds of the tamarack. This tree will not survive in upland areas.

Here is a description of preferred, staple and emergency foods for deer in Michigan. Note which of the above species are considered preferred, staple and emergency foods in this state. Palatability can vary for different plant species in different geographical locations (although Michigan is similar to Wisconsin, ecologically).

Plants to Avoid
The following plants and their cultivars have the potential to invade wild areas and out-competenative species, degrading habitats and causing extensive ecological damage.

Trees
common buckthorn + (G) (Rhamnus cathartica)
glossy/columnar buckthorn + (G) (Rhamnus frangula)
frangula)
European Mountain Ash (Sorbus
aucuparia)
Amur maple + (G) (Acer ginnala) - note that the web site says it "does not pose a problem as an invasive species"
Norway maple (Acer platanoides)
black locust (Robinia pseudoacacia)
Chinese elm (Ulmus parviflora)
Siberian elm (Ulmus pumila)
European or black alder (Alnus
glutinosa)
white poplar (Populus alba)
Lombardy poplar (Populus nigra italica)

Shrubs
all bush honeysuckles + (G) (Lonicera tatarica,
L. x bella, L. morrowii, L. aackii)
Japanese barberry (Berberis thunbergii)
European barberry (Berberis vulgaris)
multiflora rose + (G) (Rosa multiflora)
European cranberry bush (Vibernum
opulus)
common privet (Ligustrum vulgare)
burning bush/winged euonymus
(Euonymus alatus)
autumn olive + (G) (Elaeagnus umbellata)
Russian olive (Elaeagnus angustifolia)
smooth sumac (Rhus glabra)

Vines
round-leaved bittersweet (Celastrus
orbiculatus)
wintercreeper (Euonymus fortunei)
Japanese honeysuckle (Lonicera japonica)
porcelain berry (Ampelopsis
brevipedunculata)
periwinkle (Vinca minor)
English ivy (Hedera helix)

Forbs

Garlic mustard + (G) (Alliaria petiolata)

Alliaria petiolata is an herbaceous, biennial plant with white four-petaled flowers and long, linear fruits. The seeds germinate early in the spring and the seedlings soon produce numerous blunt leaves which only extend a few inches above the ground level. In dense populations the first-year leaves may block virtually all sunlight from reaching the ground, thereby interfering with any other plants growing in the area. The leaves store energy in the large roots, and both the leaves and roots overwinter, the leaves remaining green throughout. In the second year the plants develope a vertical stem up to 3 or 4 feet tall with the familiar blunt, petiolate leaves at its base and smaller, more pointed and nearly sessile leaves towards its top. The plants begin to flower in May and quickly produce the long linear fruits, each of which splits open at maturity to release numerous small, blackish seeds. Several other species of plants may look roughly similar, but only Alliaria will smell like garlic if a fresh leaf is crushed.

Alliaria is one of the most threatening of invasive plants because it can thrive in our natural woodlands and essentially eliminate our native wild flowers. The spring wildflowers of deciduous forests are almost symbolic of Wisconsin's wild places and few if any are immune to the spread of Garlic mustard. Forests on more acid soils seem to be less suitable for good growth of Alliaria and basic soils are more favorable.

Alliaria is very difficult to control once it has become well established on a site. The best method of control is to prevent colonization to begin with. Prioritize sites to be protected, monitor all sites annually and remove new colonists as soon as possible. Since the plants do not produce seeds in the first year, there is a full year (from the spring they germinate through the following spring) to find the invaders before they can produce seeds to expand the population. The first-year leaves remain green and are often highly visible in Fall and intoWinter until they are covered with snow, and again after the snow melts in the spring, providing a long period for detection.

For sites already infested with Alliaria, a great deal of effort is required to reclaim the area. It is best to resist the first urge to grab a tool and wade into the middle of the worst patch you can find. Such sites can scarcely get worse, and remember that people are one of the primary sources for carrying the seeds to new sites, so you may do more harm than good if you spread the plant to new areas via seeds on your shoes and clothes. A better plan is to survey the area and begin working to eliminate the outlying, young colonies first and then work your way in toward the heavier density areas. If the plants have been on any site long enough to produce seeds, you may have to repeat the removal of plants each year for 5-10 years or more. And of course the potential exists for new colonizations in the future, so Garlic Mustard monitoring will be a permanent necessity.

Spotted knapweed + (G) (Centaurea biebersteinii)

Spotted knapweed is a serious invader of sunny sites and is especially troublesome in Wisconsin on sandy sites of low productivity, including grasslands, barrens and great lakes dunes and beaches. It frequently invades sandy fields or pastures and can form nearly pure stands after a few years. Disturbance of the land encourages spread of spotted knapweed, but it can invade undisturbed dunes and other natural communities even in the absence of disturbance.

Spotted knapweed appears to produce substances that inhibit the growth of other plants nearby (it is therefore said to be "allelopathic"). It is also unpalatable to most animals and it is not controllable by fire. Development of biological controls is underway and some success has been achieved through repeated mowing or hand cutting or pulling of plants, but it must be a dedicated, continuous program applied over several years--until the seed bank has been exhausted. Instructions for chemical control (and other methods as well) can be found at several locations on the web including this Nature Conservancy site.
As is the case for most invasive species, the best management is to monitor on a regular basis and to find and destroy new populations when they are small. Small populations can be hand pulled or the flower heads removed until the population is eliminated. People working at control of spotted knapweed are advised to wear sturdy gloves, as there is some suspicion that repeated contact with the plants can be hazardous.