SILVICULTURAL, MANAGEMENT OF BLACK SPRUCE IN MINNESOTA 53 



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Figure 27. — Understory black spruce left after a 65-percent cutting in 85-year-old 

 jack pine was uprooted within 3 months by the first strong wind. ' Kawishiwi 

 Experimental Forest. 



Its serotinous cones, borne at the tops of the trees, disperse the 

 enclosed seeds slowly over a period of 2 or 3 years after ripening. The 

 seeds stored in the cones account for the success of black spruce in 

 reseeding after forest fires. The slow dispersal of the seed also is of 

 value in assuring a supply of freshly scattered seed when stands are 

 cut over. 



Seedlings as well as older trees can endure much shade but are most 

 successful in sunlight. The seeds germinate best on exposed mineral 

 soil, rotten wood, and peat. 



Black spruce trees grow slowly and in Minnesota rarely attain 

 breast high diameters larger than 17 inches. Growth is well-sustained 

 up to about 100 years on good sites, 140 years on medium sites, and 



