- Balsam Fir
Beginning at age 30, balsam fir produces good seed crops every two to four years. Wind disperses seed for 80 to 200 feet from mature trees. If enough moisture is available, seeds will germinate on almost any seedbed and seedlings will survive for several years with only 10 percent of full sunlight. The best seedbed is medium-textured mineral soil with some shade. Thick duff with no shade is a poor seedbed. Scarification that incorporates duff will improve the seedbed.
Because balsam fir is very shade tolerant, it can be managed in uneven-aged stands, especially on moist-wet sites. Use a two-stage shelterwood harvest, leaving 60 percent crown cover where advance regeneration is not adequate and where residual firs are known to be windfirm (resistant to strong winds).
Balsam fir also can be managed in even-aged stands by clearcutting in alternate or progressive strips or patches. Use clearcutting where the shel- terwood system will lead to excessive mortality from rot, wind, or spruce budworm or where ad- vance regeneration of fir is well established before the cut. Cut strips perpendicular to, and progress- ing toward, the prevailing wind. Cut strips up to three chains wide with seeding from both sides or two chains wide with seeding only from the wind- ward side.
Excessive slash from harvesting will hinder growth of advance regeneration and provide too much shade over a seedbed. Reduce slash by full-tree skidding.
Balsam fir is seldom planted because of low mar- ket demand and the relative ease of regeneration by natural seeding.
Depending on site conditions and the tree species mix that is present, a balsam fir stand can be con- verted to other forest types. In a mature stand of fir with some aspen, clearcut to produce a stand of aspen suckers with scattered firs. If advance fir re- generation is sparse, place harvest areas within two to three chains of seed-bearing firs. Firs will grow up with the aspen. Once the aspen has matured, cut the aspen, being careful to preserve the firs for longer growth. Some aspen will regenerate in the openings, sustaining a two-species stand. When the firs mature, repeat the cycle by clearcutting.
Where balsam fir forms an understory beneath paper birch, clearcut the birch to release the fir. To reduce spruce budworm problems, maintain some overstory birch by clearcutting progressive strips or small patches. To ensure a birch component in the new stand, scarify the soil in scattered openings and leave seed-bearing birches within three chains. In a balsam fir stand with at least three to five pa- per birch seed trees an acre, you can retain a birch component by clearcutting the stand in progressive strips or small patches or using shelterwood cut- ting. Cut strips one to two chains wide and patches one acre or less. Scarify about 50 percent of the harvest area to prepare seedbeds for fir and birch. Whole-tree skidding when the soil is not frozen or snow covered will scarify the site. About eight years after the harvest, thin the new stand to man- age the mix of fir and birch.
In northern hardwood stands with a balsam fir component where the site index for sugar maple is greater than 55, control fir advance regeneration to favor hardwood reproduction and clearcut mature fir if hardwood advance reproduction is adequate. Adequate stocking is 5,000 hardwood seedlings three to four feet tall or 1,000 saplings two to four inches DBH. If hardwood reproduction is not ad- equate, remove the firs in two or more shelterwood harvests to favor hardwoods.
On less well-drained hardwood sites (with a sugar maple site index of less than 55) manage balsam fir along with other hardwoods. These include yellow birch (plus eastern hemlock in Michigan and Wis- consin) on somewhat poorly drained sites and black ash and red maple on poorly drained sites. To grow only pulpwood, clearcut where fir advance growth is adequately stocked and use shelterwood harvest where it is not. To grow both pulpwood and saw- logs, thin young stands to obtain the desired mix of fir and hardwoods. Then harvest the fir at about age 50 and leave the hardwoods until they mature (at roughly age 100). When the hardwoods are mature, reproduce all species as described above. Selection cutting is suitable where a high proportion of fir is desired.
Where balsam fir occurs with pine on dry to moist- dry sites (usually sandy soils), encourage red pine (or jack pine on very dry sites) by eliminating all fir when harvesting pines.
Balsam fir often forms an understory in mature white pine stands on moist to moist-wet sites. This understory may improve wildlife habitat or esthet- ics, but for timber production the fir should be removed to facilitate regeneration of white pine or other conifers.
On moist to moist-wet sites where balsam fir is mixed with white spruce, spruce is preferred because of its higher timber value, longer life, and greater tolerance to spruce budworm defoliation. If a mature fir stand has more than 500 well-distrib- uted white spruce that are three feet or taller an acre, clearcut the stand to release the spruce, but take care to minimize logging damage. If spruce regenera- tion is not adequate, either use shelterwood cutting and scarification to encourage spruce or clearcut the stand and plant white spruce. As the new stand grows, weed out balsam fir during thinnings.
On moist-wet to wet sites where balsam fir is mixed with northern white-cedar and black spruce, minimize the fir component. Broadcast burn har- vest sites to eliminate woody debris and undesir- able small trees and shrubs to create a good seed- bed for white-cedar and spruce