Case Study Name (Landowner)

Red Oak & Northern Hardwood Thin/Group Selection (Aitkin Cty, MN)

Stand Information
State or Province: 
Minnesota
Nearest city or town: 
Malmo, MN
Landowner: 
Aitkin County
Cover-type: 
MN ECS Native Plant Community System: 
Plant community or habitat classification and growth stage: 
MHn35 and MHn47 (Section 4 - was mapped in 2010), Northern Hardwoods and Red Oak (CSA cover type "20" & "30")
Forest Health Threats: 
Estimated year of stand origin: 
1928
Silviculture System: 
Brief silvicultural objective: 
Create a high quality, structurally diverse (un-even aged) hardwood forest via implementation of a variable density treatment (crop tree release / group selection harvest).
Treatment area: 
104 acres
Overview

Aitkin County manages over 2100 acres in sections 4,5,8,9 of Seavey Township - approximately 6-miles east of Malmo, MN (east side of Lake Mille Lacs). Much of that acreage is in high quality hardwoods 80-100 years of age. The objective in this area is to manage for large blocks of mature, closed-canopy hardwood forest. Traditional un-even age management tends to favor shade tolerant sugar maple at the expense of shade intolerant species such as oak, basswood, or birch. There had been some "selective harvesting" in the area 20+ years ago and canopy gaps created at that time now contain pole sized oak, basswood, and paper birch. 

Pre-treatment stand description and condition
Pre-treatment growth and stocking: 

Pre-harvest basal area
Oak =               53
Maple =           31
Aspen =           20
Birch =             14
Basswood =     10
Other =            3
Total =             131

What actually happened during the treatment

The treatment at this site was an irregular thin via crop tree release to encourage growth on quality trees with approximately 10% of the area in canopy gaps (1/3 to 1-acre gaps) to encourage regeneration of shade intolerant species. The harvest occurred in the winter of 2010/2011 and, due in large part to timber volume from the canopy gaps,  yielded over 10-cords per acre which made it economically operable for the logging operation.

Post harvest basal area
Oak =               33
Maple =           20
Aspen =           6
Birch =             7
Basswood =     7
Other =            3
Total =            76

Post Harvest
Trees/acre = 83                                  Average DBH = 14"
Quality trees/acre = 21                      Snag Basal area = 5

Post-treatment assessment

A regeneration survey was conducted in the fall of 2013 (3-years post harvest) to monitor regeneration. Five of the canopy gaps were sampled and the initial results are encouraging for intolerants (maple seedlings were abundant but were not counted). Follow-up regeneration checks will occur at 3-5 year intervals. 

For regeneration data, see the table in "Photographs" below.

Plans for future treatments

It is anticipated that the next harvest entry will be in approximately 15-years.

Issue for the next entry... disbursed vs. expanding canopy (regeneration) gaps.  

Photographs
Regeneration table 2015Oak regeneration, pictured October 2016Yellow and paper birch regen, pictured October 2016
Keywords
Biography
Name: 
Mark Jacobs
Organization: 
Aitkin County Land Department
Phone Number: 
(218) 927-7364
Name: 
Bob Kangas
Organization: 
Aitkin County Land Department
Phone Number: 
(218) 927-7364