Warroad Jack Pine Regen Through Scarification and Aerial Seeding (MN DNR)

State or Province
MN
Nearest city or town
Warroad, MN
Describe the location
E1/2 of the NE 1/4 Section 19 T161 R36w Roseau County
Landowner
Minnesota Department of Natural Resources- Warroad Area
Cover type
MN ECS
Kotar
Plant community detail and growth stage
Young jack pine on fire dependent, north, well drained, poor nutrients (FDn12). Jack pine averages 2-3 inches DBH and 8 feet tall.
Forest health threats
Adaptive silviculture options
Silviculture system
Estimated year of stand origin
1900
Additional information about stand origin
Stand was likely established naturally following a disturbance in the early 1900s
Site index
65
Brief silvicultural objective
Harvest standing jack pine and aerial seed back to jack pine with mechanical site prep.
Site preparation method
Soil details
Hiwood fine sand A,E 0-3 inches: Fine sand Bw1,Bw2 3-22 inches: Fine sand C1-C4 22-80 inches: Fine sand
Stand area
24 acres
Treatment area
20 acres

48.753137, -95.333581

Silviculture Objective(s)

Clearcut harvest pine and regenerate stand back to pine cover type.

Pre-treatment stand description and condition

Stand establishment and management history: 

Stand was likely established naturally following a disturbance in the early 1900s. 1988 Forest Inventory data shows that the main species was 9” DBH jack pine which was 73 years old. The jack pine averaged 60 feet in height and 28 cords per acre. The basal area of the stand was 110. Other species were balsam fir at 5” DBH and 1 cord per acre, large jack pine at 15” DBH and 3 cords per acre, and red pine at 16” DBH and 2 cords per acre. The shrub layer was reported as a combination of hazel and or honeysuckle, mt. maple, dogwood, juneberry, or upland willow that was fairly uniform in distribution and low density. A high amount of deer browse was also recorded.

The 2003 cruise notes show a loss in timber volume from 34 cords an acre in 1988 to 26 cords an acre in 2003. This loss in volume was likely caused due to the stand being over mature.

Silviculture Prescription

The stand was clearcut harvested with boundaries marked with paint. 20 acres of the 24 acre stand were harvested with the remaining 4 acres reserved. All red pine and nonhazardous snags were reserved within the harvest area. Cutting was allowed between freeze-up and march 1st while cutting outside of the period required forester approval. The slash was to be lopped and scattered evenly within the harvest area. The site was then to be planted the following year back to pine.

What actually happened during the treatment

Harvest operations began in June 2004 and were completed by the end of the month. The original prescription involved planting to pine but instead the stand was mechanically scarified and aerial seeded. Aerial seeding was chosen over planting as it suited the site better than planting. The site was scarified in October of 2004 using a Leno (Patch Scarification) which made two passes over the site. In April 2005 the stand was aerial seeded at 2 ounces per acre to supplement seed from the scattered slash.

Post-treatment assessment

Regeneration checks:

2008:

Species

Seedlings per acre

Stocking %

Average Height (Ft)

Min Height

Max Height

Free to Grow %

Jack Pine

545.45

63

1

1

1

50-74

Hazel

454.55

9

2

2

2

na

2010:

Species

Seedlings per acre

Stocking %

Average Height (Ft)

Min Height

Max Height

Free to Grow %

Jack Pine

755

100

2.5

2

3.5

75-100

Balsam Fir

11

11

3

3

3

75-100

Choke Cherry

156

55

2

1

3

na

Hazel

211

55

2.5

2

3

na

Willow

133

33

3

2

4

na

2015:

Species

Seedlings per acre

Stocking %

Average Height (Ft)

Min Height

Max Height

Free to Grow %

Jack Pine

950

100

7

3

8

75-100

Paper Birch

30

28

15

10

15

75-100

Quaking Aspen

200

5

11

10

15

na

Figure 1: Jack pine regeneration.

Plans for future treatments

Monitor growth and harvest when stand has reached rotation age

Costs and economic considerations

Spring 2003 the stand was cruised and appraised at 440 cords
December 2003 the stand was bid up 71% at auction for a value of $19563.20
June 2004 harvest operations began
October 2004 stand mechanically site prepped for a cost of $1362.98
December 2004 final scale reported a underrun of 1.3%
April 2005 stand was aerial seeded at a cost of $387.59

Hand planting sites is known to provide more consistent stocking but at an added cost in comparison to aerial seeding. Using mechanical site preparation with aerial seeding may provide a way to obtain desired stocking with a lower cost than that of hand planting.

Seeding cost 2005
Site prep: $68.15/acre
Seeding: $19.40/acre
Total cost per acre $87.55

Planting cost 2005
Site prep: $68.15/acre
Planting: $190/acre
Total cost per acre: $258.15

Summary / lessons learned / additional thoughts

The aerial seeding with mechanical site preparation was successful in producing adequate stocking level, trees per acre, and free to grow status for jack pine throughout the site. If only one regeneration check was done in 2008 it would have produced results that would have labeled the stand for future treatments (such as supplemental planting). While the 2010 and 2015 regeneration checks resulted in sufficient regeneration, this emphasizes the need for multiple regeneration checks over the first few years of a stand’s life.

Figure 2: Jack pine regeneration.