SYLVICULTURE. 



Elm shade bearer. 



Birch light demander or intermediate. 



Black walnut intermediate. 



Linden shade bearer. 



Umbrella tree less light demanding than Yellow Poplar. 



Cucumber less light demanding than Yellow Poplar. 



Sycamore medium shade bearer. 



Willows and Cottonwoods light demanders. 



Liquidambar light demander. 



Hickories light demanders. 



c. Western Conifers : 



Douglas Fir intermediate. 



Ponderosa light demander. 



Nut Pines intense light demanders. 



Lodgepole Pine intermediate. 



Sugar Pine intense light demander. 



Lawson Cypress intense shade bearer. 



Tide-land Spruce shade bearer. 



Redwood shade bearer. 



Western Hemlock intense shade bearer. 



Western Firs intense shade bearers. 



Larch intense light demander. 



Engelmann's Spruce shade bearer. 



Colorado Blue Spruce shade bearer. 

 Paragraph VII. Pure versus mixed woods. 



A. Conditions inviting pure woods and mixed woods. 



Conifers are more apt to grow in pure forests, owing to their 

 greater modesty. Abroad, up to a very recent time, the desire of 

 the forester was to raise mixed woods, but quite recently the 

 " Danish propaganda " has turned the minds of some foresters back 

 to pure woods. 



Severe climatic conditions and poor soil conditions invariably 

 give one species the preponderance, for example: Bald Cypress rules 

 in the swamps of the South, Tamarack in those of the North; Nut 

 Pines prevail in the semi-arid regions of the Southwest; Long Leaf 

 Pine on poor sand in the South; Cuban Pine in half swamps of the 

 South ; Red Spruce on the " Black Slopes " of the Adirondacks ; 

 White Spruce in Northern Canada; Lodgepole Pines on old burns; 

 Jack Pine on poor sand in the Lake States. 



Pure forests are sometimes in the interest of the owner, for 

 example: Pure Spruce near paper mills; Hickory, near carriage 

 works; Tan Bark Oak near tanneries. 



34 



