Minnesota’s northern white-cedar forest type
Products and Uses
The demand for good northern white-cedar lumber is strong, but many mature stands do not have enough volume for a commercial harvest. White-cedar also is used for fence posts and poles. The white-cedar forest type is valuable for deer yards, but some have inadequate shelter or browse. Deer habitat is best if white-cedar stands at different stages of development are interspersed throughout the forest.
Northern white-cedar grows in pure stands but is more common in mixed stands. Common associates on wetter soils include balsam fir, black spruce, white spruce, tamarack, black ash, and red maple. Onbetter drained and upland soils, white-cedar may be found with aspen, eastern white pine, eastern hemlock, yellow birch, or white birch. It may perpetuate itself in pure stands, but other tree species seem to gradually replace it in mixed stands, particularly after disturbances.
Northern white-cedar grows best on limestone-derived soils that are neutral or slightly alkaline and moist but well drained. It also grows well on well-decomposed, neutral or slightly alkaline organic soil derived from woody plants or sedges and on organic soils in which the upper 4 inches are poorly decomposed sphagnum or other mosses. The best sites have moving soil water and usually are near streams or other drainageways. The poorest sites have poorly decomposed acid soil throughout the whole root zone that is derived from plants such as sphagnum moss. These sites have little water movement (except during snowmelt) and often are far from drainageways.
Rotation lengths range from 70 years for posts up to 160 years for poles or small sawlogs. When stands are managed for deer shelter, rotations should run at least 110 years.
Range of northern white-cedar.
Northern white-cedar is shade-tolerant and can be managed under the single-tree selection or clearcutting systems. A clearcut or shelterwood harvest followed by natural seeding is the usual regeneration method. If advance reproduction is not present, a combination of clearcut and shelterwood strips is recommended to optimize natural seeding. Strips vary from 1 chain wide where seedbearing trees are less than 35 feet tall to 2 chains where these trees are more than 60 feet tall. Use either alternate or progressive strips. If you use alternate strips, clearcut one set, then cut the adjoining strip in two stages using the shelterwood system about 10 years later.
For the first stage of the shelterwood, leave a basal area of 60 square feet per acre in uniformly spaced dominant and codominant trees of desirable species. Select residual trees for good seed production, wind-firmness, and timber quality. The second stage of the shelterwood, the final clearcut, should occur about 10 years after the seed cut. If you use progressive strips, work with sets of three-the first two being clearcut at 10-year intervals and the third one cut in two stages as previously described.
You may need to control associated trees before the final harvest if you want to obtain 50 to 80 percent white-cedar on good sites managed for timber or deer habitat. Kill undesirable trees (especially hardwoods) that reproduce by root suckers or stump sprouts at least 5 and preferably 10 years before reproduction cutting.
Rely on residual stems to reproduce a stand only if there are at least 600 stems per acre of relatively young (less than 50 years old) and healthy white-cedars remaining. Remove heavy slash that buries residual stems or seedbeds. Full-tree skidding in winter will remove most slash and is recommended where residual trees will be relied on for reproduction. Either full-tree skidding or burning may be used for slash disposal in clearcut strips.
White-cedar is relatively free of major insect and disease problems. Wind may cause breakage and uprooting, mainly along stand edges and in stands opened up by partial cutting. White-tailed deer and snowshoe hare commonly browse northern white-cedar so severely that a stand cannot become established. Overbrowsing may be minimized when regenerating stands if large patches (40 acres or more) are completely cleared. Roads, beaver dams, and pipelines that impede the normal movement of soil water will kill northern white-cedar.
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