SYLVICULTURE. 



Young plants suffer from mice. Damaged seedlings should be 

 coppiced down. 



J. Hicoria minima: Height growth quicker to begin with than 

 in Shagbark. 



At 20 years, however, Shagbark ca.tches up. 



Wood much poorer than in Shagbark (more brittle). 



K. Hicoria glabra: Like Shagbark; more modest as to soil; 

 more sensitive as to frost (?). 



L. Hicoria alba: More sensitive than Shagbark; same rate of 

 growth; does well in the Westerwald, badly in river valleys. 



Paragraph XXXVIII. Results of planting experiments with American 

 softwoods. 



A. Pinus divaricata: Very modest: Stands frost and drought 

 and does not shed needles. 



Root system tap-rooted, many fibred. 



Height growth very rapid, several shoots per summer. Better 

 than Scotch Pine. 



2 years old, 8 inches high. 



5 years old, 5 feet high. 



8 years old, 10 feet high. 



Game and hares handicap it, still there is strong reproductive 

 power. 



Seed one-half pound per square pole; seed has 60% germination; 

 cones fertile from sixth year on. 



Use yearlings or transplants two to three years old for the very 

 poorest soil. 



B. Pinus ponderosa: Fails absolutely in Germany, probably 

 owing to insufficient summer heat. 



C. Pinus rigida: Very modest; does well in salty swamps; 

 suffers badly from snow-pressure. 



When 5 years old, 7 feet high. 



When 20 years old, 32 feet high. 



Growth is very rapid, but from 12 years on P. sylvestris catches 

 up and then keeps ahead. 



Diameter growth better than in sylvestris, too. 



Strong reproductive power after insects, game, fire. 



Very light demanding. 



Cones seed-bearing from twelfth year on. 



More proof against late frost, more sensitive for early frost than 

 sylvestris. 



Less shedding of needles; more danger from game. 



Use yearlings, or transplants two years old. 



90 



