F — 243286 



Figure 6.— Remnant of I'iigin white and red pine in Mirhii^an: 

 Hartii'ick Pines State Park. Only small scattered tracts of 

 this kind of timber remain in the region. 



The red pine type, occurring mostly in seedling 

 and sapling stands, now occupies less than 1 million 

 acres. However, it is being planted more extensive- 

 ly than white pine (fig. 8), and in some localities is 

 replacing jack pine through process of natural 

 conversion (H)- 



The jack pine type has supj^lanted -ivhite and 

 red pine on sandier soils (lO) and now occupies 

 more land than the two other pine types combined. 

 Most of the jack pine stands still are immature 

 (fig. 9), and some are very poorly stocked. 



Spruce-fir group: This group is divided into four 

 forest types (table 5): 



The white spruce-balsam fir type occurs on 

 moist upland sites and s\vamp margins in the 

 northern part of the region. Balsam fir is the key 

 species. Aspen, paper birch, and other hard^voods 

 commonly have supplanted the \vhite spruce in 

 second-growth stands (fig. 10). 



The black spruce type occurs primarily in peat 

 swamps where conditions for tree growth are rather 



F — 433097 



Figure l.—Second-groicth while pine on Superior National 

 Forest, Minn. Acreage of pure type is very limited but 

 scattered white pine trees are found in other types. 



unfavorable (19). Ho^\•ever, because of the high 

 demand for the species for pulp, the type is one of 

 the more valuable in the region. Around s\\amp 

 margins, black spruce grows fairly rapidly and some 

 100 thousand acres in such situation can be classed 

 as small saw-timber stands. To^vard the center of 

 the swamps, the gro\ving conditions become less 

 favorable and most stands mature at pole-timber 

 size (fig. 11). Under the worst drainage and cli- 

 matic conditions, the black spruce will not yield 

 merchantable crops of pulpwood at 100 years of 

 age (fig. 12), and consequently such stands have been 

 classified as noncommercial. 



The tamarack type occupies sites similar to those 

 for black spruce, but it is less extensive. Tamarack 

 is valued primarily as a mine-timber and fence-post 

 Avood, although it has been pulped to a iiniiicd 

 extent. 



8 



Furc'il Resource Report No. I. C. S. DeparhnenI of .4gricult iirc 



