,THE SUITABILITY OF AMERICAN WOODS FOR PAPER PULP 27 
By Mechanical Process 
Reduces readily. 
Pulp: Of excellent color and standard strength. 
Power required: Comparable to that for white spruce. 
Uses to which pulp is suited: Practically all uses requiring ground wood. 
Norway Spruce {Picea abies, formerly P. excelsa) 
Other names in use. — Spruce, fir, common spruce, and white fir. 
Range. — From the Urals and Lapland to the Pyrenees and Alps. Planted in 
the eastern United States. 
Oven-dry weight per cubic foot, green volume. — 30 pounds. 
Fiber length. — 
By Sulphite Process 
Reduces readily. 
Unbleached pulp: Strong, of fine texture and excellent color; bleaches easily 
to excellent white. 
Yields: 45 to 50 per cent. 
Bleach required: 10 to 20 per cent. 
Uses to which pulp is suited: News, wrapping, book, high-grade printing, and 
bond papers. 
By Sulphate Process 
Reduces readily. 
Unbleached pulp: Strong, of fine texture. 
Yields: 45 to 50 per cent of strong pulp; 38 to 43 per cent of pulp for 
bleaching. 
Bleach required: 20 to 30 per cent in one stage, or 15 to 20 per cent in two 
stages. 
Uses to which pulp is suited: High-grade kraft wrapping papers and fiber 
board. 
By Mechanical Process 
Reduces readily. 
Pulp: Of excellent color and standard strength. 
Power required: Comparable to that for white spruce. 
Uses to which pulp is suited: Practically all uses requiring ground wood. 
Red Spruce (Picea rubra, formerly P. rkbens) 
Other names in use. — Yellow spruce. Trade names of the lumber are eastern 
spruce, West Virginia spruce, Canadian spruce, and Adirondack spruce. 
Range. — Prince Edward Island southward to the coast of Massachusetts and 
through New England and New York and northern Pennsylvania to North 
Carolina and Tennessee (high mountains). Range imperfectly known. Over 
three-fourths of the present stand is in New England and New York. 
Oven-dry weight per cubic foot, green volume. — 24 pounds. 
Fiber length. — 3.7 mm. 
By Sulphite Process 
Reduces readily. 
Unbleached pulp: Strong, of fine texture and excellent color, although occasion- 
ally somewhat pitchy; bleaches easily to excellent white. 
Yields: 45 to 50 per cent. 
Bleach required: 10 to 20 per cent. 
Uses to which pulp is suited: News, wrapping, book, high-grade printing, and 
bond papers. 
By Sulphate Process 
Reduces readily. 
Unbleached pulp : Strong, of fine texture. 
Yields: 45 to 50 per cent of strong pulp. 
Bleaching properties probably similar to those of white spruce. 
Uses to which pulp is suited: High-grade kraft wrapping papers and fiber 
board. 
By Mechanical Process 
Reduces readily. 
Pulp: Of excellent color and standard strength. 
Power required: Comparable to that for white spruce. 
Uses to which pulp is suited: Practically all uses requiring round wood. 
