UNITED STATES DEPARTMENT OF AGRICULTURE 
DEPARTMENT BULLETIN No. 1298 
Washington, D. C. T April, 1925 
CONTROL OF DECAY IN PULP AND PULP WOOD 
By Otto Kress, formerly in charge, Section of Pulp and Paper, Forest Products 
Laboratory; C. J. Humphrey, Pathologist, and C. A. Richards, Assistant 
Pathologist, Office of Investigations in Forest Pathology; M. W. Bray, Chemist 
in Forest Products, and J. A. Staidl, Assistant Engineer in Forest Products, 
Forest Products Laboratory, Forest Service, in cooperation with Bureau of Plant 
Industry 
CONTENTS 
Page 
Importance of decay problem in pulp industry l 
Decay of wood 4 
Conditions necessary for growth of fungi 5 
Fungi that decay stored pulp wood f> 
Storage of pulp wood f. 
Character of wood available for pulping 
Length of storage period 7 
Handling of pulp wood at woods points 7 
Storing pulp wood at the mill 8 
Summary of recommendations 12 
Pulping characteristics of decayed woods H 
Physical properties of mechanical pulp made from sound and from decayed spruce 14 
Physical properties of sulphite and soda pulps made from sound and from decayed wood 16 
Chemical properties of sound and decayed woods and pulp from sound and decayed spruce 20 
Spruce wood and spruce mechanical pulp 20 
Hemlock, balsam, and aspen woods 23 
Spruce sulphite pulp 24 
Spruce soda pulp 24 
General discussion of chemical data 25 
Storage of pulp 25 
Length of storage 2(5 
Deterioration during storage 26 
Physical properties of pulp decayed in storage 29 
Preservation of pulp by chemical treatment 31 
Work of other investigators 32 
Experimental procedure 33 
Results of preservative treatments 36 
Preservatives recommended for mill application 48 
Summary 49 
APPENDIX 
Studies of specific fungi that deteriorate wood pulp 52 
Work of prior investigators... 52 
Materials and methods employed 56 
Fungi observed 56 
Physical and chemical properties of ground-wood pulp deteriorated by specific fungi in pure cul- 
tures -- 67 
Physical properties 67 
Chemical properties Jt - 74 
Bibliography 79 
IMPORTANCE OF DECAY PROBLEM IN PULP INDUSTRY 
The pulping of wood for the production of paper and various fiber 
products is one of the major industries of the United States. It is 
largely concentrated in the northern region beginning with Minnesota 
and extending eastward. The six leading pulp-producing States 
523°— 25t 1 
