In 1992, Camp 8 was described as follows: “There are approximately 75 old-growth pine per acre. [These trees] have an average DBH of about 17 inches and there are approximately 26 thousand board feet (MBF) per acre. The stand today has a moderate to heavy understory of shrubs, balsam fir, spruce, white pine, and hardwoods. Present tree mortality is moderate in pockets but light throughout the stand.” Later, in the 2002 management plan, Ron Severs noted “Periodic fires could be used to control the understory in the managed portion of the stand… From 1992 to 2002… two prescribed burns were accomplished. Both burns had minimal effect on reducing woody understory vegetation. A combination of limited personnel and infrequent safe burning conditions were major limiting factors preventing effective and regular burns.”
In 2009, the 1984 treatment was repeated: 19.5 tons/acre of mixed species chips were removed from the understory. Unlike the 1984 treatment, however, some white pine regeneration was retained. Ron Severs notes in the 1992-2001 Cloquet Forestry Center Management Plan that “this prescription doesn’t include any specific recommendations for stand regeneration at this time. The presence of the disease red pine shoot blight (Sirococcus strobilinus) on the forest would preclude trying to establish regeneration under the overstory, and the time at which the stand will lose the characteristics for which it is being preserved is indeterminable.” In addition, a pocket of Armillaria mortality is believed to have formed following the 2009 treatment.
Current Stand Conditions
Camp 8 was cruised in 2018. The treated side was found to have a basal area of 160 square feet per acre; of those 160 square feet, 143, or 89 percent, were comprised of red pine and 13, or 8 percent, were comprised of white pine. Of the 93 trees per acre, there were approximately 75 red pine and 6 white pine per acre in the stand. Much of the basal area for red pine is in the 16 to 22 inch DBH classes (figure 1). There is some balsam fir around the perimeter of the untreated half, particularly on the west edge, and figure 2 shows there are approximately 12 balsam fir per acre. There are also 7 red pine snags per acre.
These numbers are in contrast to the untreated stand where the red pine are being overloaded by other species in the smaller diameter classes such as balsam fir and red maple as well as some aspen and birch. The untreated stand has a basal area of 221 square feet per acre, and while 75% of the basal area is comprised of red pine and another 8% are white pine (figure 3), the stand is at considerable risk for a crown fire due to the density of the stand as well as the presence of ladder fuels (figure 4). In addition, there is likely little to no red or white pine regeneration due to heavy competition in the understory, particularly balsam fir. Balsam fir, while representing about 8% of the total basal area, accounts for almost a quarter of the trees per acre. There are about 23 snags per acre and almost half of them are red pine.