CROP PLANTS FOR PAPER MAKING. 11 



is from 3 to 4 hours, as compared with 8 to 12 hours for wood. In 

 addition, preliminary tests indicate that there will be no great diffi- 

 culty in recovering the caustic soda used in digestion. 



In tests on a laboratory and semicommercial basis, yields of 32 to 

 40 per cent of fiber were obtained. Later, a cook of 3^ tons was 

 made in the largest sized rotary digester in common use for wood, 

 on which a yield of practically 42 per cent was obtained.^ It 

 appears from this that it will be safe to expect this percentage of 

 fiber in actual practice. It was found that the proportion of pith 

 in broom-corn pulp is so low that it could be made directly into a 

 fair quality of white paper, which, however, would probably be too 

 brittle for most purposes. Experiments were also made to test the 

 effect of combining broom-corn pulp with certain proportions of 

 soda pulp from poplar and sulphite pulp from spruce. It was found 

 that a combination of 50 per cent of unseparated broom-corn pulp, 

 pith, and long fiber, together with 50 per cent of poplar, produced 

 what was pronounced by practical paper men as a merchantable 

 quality of book paper. In combination with sulphite fiber from 

 spruce a stronger though somewhat harsher sheet resulted. 



The results that have been secured with broom-corn stalks indicate 

 that this material is suitable for immediate use in paper making, on 

 the basis of both quality of fiber produced and yield of fiber secured. 

 Broom-corn stalks have one serious disadvantage, namely, the limited 

 production of raw material. The figures for the recent census are 

 not yet available, but according to the returns of the Twelfth Census 

 178,584 acres were devoted to broom corn in 1899. The yield of 

 stalks to the acre will probably approximate very nearly 3 tons; 

 hence, the quantity produced Avill probably be in the neighborhood of 

 450,000 tons. Many States grow small acreages of broom corn, but 

 Illinois, Kansas, Oklahoma, and Missouri probably produce fully two- 

 thirds of the total crop. It is possible that in these States there may 

 be localities where the acreage cultivated near one central point is 

 so large that pulp could be produced economically. 



The harvesting of the stalks for pulp making does not interfere 

 with the harvesting of the brush for brooms, nor would it in any way 

 reduce the quality of the brush produced. 



Broom-corn stalks, like cornstalks, yield a product under water 

 extraction containing practically the whole food value of the raw 

 material. In the case of broom corn it seems likely that the stalks 

 could be pulped at a profit without taking into account the possible 

 value of the food extract. 



* .\cknowledgment is here made for much assistance and information furnished l)y S. D. 

 Warren & Co., Cumberland Mills. Me. Tlio writer is especially indebted to Mr. John E. 

 Warren, the resident agent of the company, for many helpful suggestions and hearty 

 cooperation. 



[Cir. 82] 



