Improving Deer Habitat
In the northeastern third of Minnesota, mixed aspen forest is the most important forest type for deer. Other important types are oak, balsam fir, jack pine, birch, upland brush, white cedar, and balsam poplar. Deer use jack pine forests as both summer habitat and in some cases as winter habitat in northern Minnesota. White cedar and balsam fir are very important for winter deer habitat as well. Mixed aspen-northern hardwood forests and woodlands
in the transitional deciduous forests in extreme northwestern and central portions of the state are the most important forest types for deer. In the far southeastern portion of the state oak and mixed deciduous forest are the most important forest types. During most of the year, deer prefer edges, young forests, and open areas for feeding. Although deer are adaptable, they require periodic disturbance in their environment. Timber harvesting is the best and the most economical method of creating this habitat.
Deer populations are highest in diverse forested and
in mixed farmland and forest landscapes. Specifically,
this diversity is provided by the appropriate mixture or proportion of natural vegetation (herbs, shrubs, trees)
and forest age or growth phases and structure. Periodic disturbance provides rejuvenation of young growth stages of vegetation, and habitat edge, which favors species such as white-tailed deer. In such habitats, aggressive antlerless deer harvest will likely be needed.
Today commercial timber harvests have replaced natural disturbance as the dominant method for creating early succession forest. Disturbance in grassland and brushland areas comes from farming activity, use of mechanical equipment for cutting, “shearing,” and mowing of decadent and rank brushland areas, and prescribed or controlled fire.
Deer are wide-ranging animals, and you may not be able to provide for all their needs on your property. Your efforts will be best rewarded if you assess the habitat on your land and nearby properties. The surrounding forest habitat, within about a two-three mile radius of your property, will influence the management of your property for deer.
Decide which habitat components are in the shortest supply, such as young regenerating forest, grassy openings, acorn production, or winter cover, then provide that habitat on your land.
Habitat management for deer will also benefit ruffed grouse, woodcock, sharp-tailed grouse, and many nongame wildlife species associated with the early developmental
or succession growth stages of open brushland and mixed deciduous forest habitat.
Maintain a diversity of deciduous and coniferous forest, a high proportion of aspen forest, a diversity of aspen forest growth phases or age groups (1-10 years through 50-65 years), and one or two acres of grassy forest openings for every 40 acres of upland forest habitat.
To improve aspen and mixed aspen forests as deer habitat, a portion should be clear-cut periodically to set growth back to the aspen sprout stage. Clear-cutting removes the tree canopy so that sunlight, heat, and rain penetrate to the forest floor stimulating plant growth. Clear-cutting can be accomplished with a commercial timber sale which benefits wildlife and provides you with income. The boundaries of a timber sale do not have to be straight lines; the shape can follow topography or other natural features. Leave tight clumps of balsam fir or jack pine un-harvested for use as winter cover. Areas of new forest growth scattered within a deer’s home range provide good deer habitat for 10-15 years.
Whitetails respond best to timber management that maintains a proportion of young, intermediate, and mature growth stages or age classes. Forest “stand” harvest in aspen-birch forest is an appropriate option for deer. To improve habitat for deer and ruffed grouse, harvest timber in patches or units 10 acres or smaller in aspen-birch and northern hardwood-oak forests.
Oaks and other hardwood species are more predominant than aspen in the hardwood forests of southeastern Minnesota. The goal is to maintain or perpetuate the oak or mixed oak woodlands by active management. These forest types can be difficult to manage. Challenges include disease outbreaks, excessive deer browsing of seedlings, and hardwood regeneration failure. Consult a resource professional to manage oak and other hardwoods in your woodland.
Oak management is influenced by the quality, condition and age of the trees present. The proportion of oak
Forest deer feed on a variety of green vegetation in summer including buds blossoms and leaves of herbs and half-shrubs.
reproduction (saplings) will be determined by other trees or shrubs that are present, soil type and woodland size, and current oak distribution of your oak woodland and (oaks scattered throughout the stand or growing in clumps). A mosaic of small (about 10 acre) regenerating cuts dominated by 5-15 foot tall oaks will allow perpetuation of oaks in your woodland.
Oak harvest strategies need to focus on reserving three to six large mast producing trees per acre to supply the important acorn crops as deer food sources and a seed source for oak regeneration. Some middle-aged oak and (if present) hickory trees should be reserved from harvest to provide future mast crops. Combined with a proper regeneration strategy, this will provide a perpetual supply of mast.
Smaller cuts or harvest areas also stimulate under-story vegetation such as fruit and berry producing shrubs, and forbs (herbaceous plants) which provide additional wildlife foods. Dense stands of younger trees can sometimes be thinned to promote acorn production and tree growth. Thinning the canopy near forest edges can promote under- story growth.
There are two methods that will produce young saplings to provide the mix of food and cover used by deer. The option you use depends on whether there already is oak regeneration (small oak trees) in the area, and the age and condition of the trees. Do not harvest oaks without professional advice. To do so invites regeneration failure.