Overview
In 2003 I set up a partial cut sale on 110 acres (stand 17-16-53-15W) designed to increase yellow birch stocking, maintain the paper birch component and expand the basswood and not expand or increase aspen. I marked the desired seed trees of the various species and also marked as many non-merchantable younger yellow birch to try and protect those that were 1-5 inch dbh. Stand was harvested in 2007. Yellow birch regeneration 9 years after treatment is good.
Figure 1: Google Maps image of the site
Figure 2: Characteristic peeling bark on a 7-inch yellow birch near Canyon MN
Figure 3: Bark of a half-inch diameter yellow birch stem
Figure 4: Bark on a 2-inch diameter yellow birch near Canyon MN
Silviculture Objective(s)
This is a relatively productive site that can support good quality birch and mixed hardwoods. The objective was to increase yellow birch stocking, maintain the paper birch component, and expand basswood while limiting aspen expansion. Target stocking was approximately 25% yellow birch, 25% paper birch, and 50% other species.
Pre-treatment stand description and condition
Stand establishment and management history:
Pre-treatment stand origin was 1908.
Pre-treatment species composition:
Red maple, sugar maple, basswood, paper birch, yellow birch, black ash, white spruce, balsam fir, white cedar, white pine.
Pre-treatment forest health issues:
No major issues, some frost cracking, etc on maple.
Silviculture Prescription
The prescription combined a release treatment for 1-2” diameter yellow birch with a harvest and simultaneous soil scarification to create favorable conditions for regeneration from seed.
Figure 5: Brush was piled during the treatment to allow soil scarification
I marked the desired seed trees of the various species and also marked as many non-merchantable younger yellow birch to try and protect those that were 1-5 inch dbh. White pine, upland white cedar, yellow birch, white spruce, basswood and upland black ash were reserved species. In addition I marked selected paper birch, sugar maple and red maple. To be safe I also marked all yellow birch to be reserved so that the operator would not mistake them for paper birch (yes they have). The site is an MHb45 and I hoped we would be able to cut it during a dry summer to produce good soil scarification and birch regeneration.
Figure 6: Large-diameter yellow-birch retained as a seed tree
The appraisal was for 920 cords of maple, 480 cords PB, 350 cords aspen, and 35 cords BF. The reserved merchantable volume were: YB 0.9 MBF & 0.7 cords, RM 1 cord, SM 1 cord, BA 0.4 cord, WP 0.9 MBF,WS 0.3 MBF, WC 1 cord, basswood 2.2 cords. The white pine are beautiful super canopy in clusters.
What actually happened during the treatment
The sale was cut August 15-October 15 2007 during a drought, using a CTL with a skilled operator. We got relatively good scarification because we didn't need to use slash mats to avoid rutting. The slash was placed in small random piles instead. This good luck of the dry soil conditions was an important factor to the early success of the treatment. Even better, steady rain began shortly after the harvest was completed.
Post-treatment assessment
In 2013 my survey showed the following. Stocking figures are per acre.
Yellow Birch 933 seedlings 0-1”,400 saplings 1-3”,25 saplings 3-5” (the larger saplings having been retained during the 2007 harvest)
Basswood 1100 seedlings 0-1”
Paper Birch 633 seedlings 0-1”
Red Maple 2150 seedlings 0-1”
Sugar Maple 530 seedlings 0-1”
Trembling Aspen 1117 seedlings 0-1”
Balsam Poplar 100 seedlings 0-1”
Balsam Fir 400 seedlings 0-1”
White Cedar 215 seedlings 0-1”
Black Ash 35 seedlings 0-1”
White Pine 15 seedlings 0-1”
White Spruce 15 seedlings 0-1”
The survey was done to determine whether any follow up TSI was needed. No follow up was needed.
Figure 7: Residual basswood, birch, and maples remain 9 years after the regeneration harvest
Plans for future treatments
Possible spot planting of red oak to test performance in this area and to reintroduce the seed source, giving future managers additional options.
Costs and economic considerations
Main investment was time and patience.
Summary / lessons learned / additional thoughts
As noted above, the fortunate timing of a dry summer for the harvest and site prep (scarification during harvest) followed by steady rain created good conditions for yellow and paper birch regeneration from seed. This saved the need for additional site prep after the harvest.