CONTENTS. 



Department Bulletin 101. — -Relative Resistance op Various Conifers 



to Injection with Creosote: Page. 



Purpose of the experiments 1 



Structure of the conifers 1 



Experimental methods 4 



Apparatus 4 



Materials used 6 



Method of applying the creosote 7 



Penetration as affected by wood structure 9 



Theory of penetrance 16 



Conclusions 17 



Appendix 18 



Department Bulletin 102. — Acidity as a Factor in Determining the 

 Degree op Soundness of Corn: 



Introduction . 1 



Method, apparatus, and reagents 1 



Degree of acidity of corn 6 



Relation of the acidity of corn to certain criteria of soundness and quality. . 11 

 Relation of acidity and germination of corn to commercial grading at ter- 

 minal markets — 19 



Acidity of corn as a factor in commercial grading . 19 



General considerations 35 



Summary 45 



Department Bulletin 103. — Alum in Foods: 



Explanatory statement 1 



Questions submitted to referee board 1 



Character of experiments conducted 1 



Conclusions of individual investigators 4 



Conclusions of the referee bo,ard 6 



Department. Bulletin 104. — Thrips as Pollinators of Beet Flowers: 



Introduction 1 



Occurrence of thrips on beet flowers 2 



Thrips as pollen bearers 4 



Experiments in the pollination of beet flowers 5 



Cross-pollination by thrips. . 9 



Injury to seed beets 10 



Trouble to plant breeders 10 



Conclusion 12 



Department Bulletin 105. — -Progress Reports of Experiments in Dust 

 Prevention and Road Preservation, 1913: 



Experiments at Chevy Chase, Md 1 



Experiments on Rockville Pike, Maryland 17 



Experiments at Miami, Fla 25 



Supplementary report of experiments made at Washington, D. C, 1912 29 



Supplementary report of experiments at Chevy Chase, Md., 1911 project. . 31 

 Supplementarv report of experiments made on Bradley Lane, Chew Chase, 



Md., 1911 . ." , 1 35 



Supplementary report of experiments made at Jamaica, N. Y., 1911 36 



Supplementary report of experiments made at New York, N. Y., and Ridge- 

 wood, N. J., 1910 40 



Supplementary reports of experiments made at Boise, Idaho, 1910 41 



Supplementary report of experiment made at Ames, Iowa, 1910 41 



Supplementary report of experiments made at Knoxville, Tenn., 1910 41 



Supplementary report of experiments made at Youngstown, Ohio, 1909. . . 42 



Supplementary report of experiments made at Newton, Mass., 1908 43 



Supplementary report of experiments made at Garden City, Dodge City, 



Bucklin, and Ford, Kans., 1908 44 



Supplementary report of experiment made at Independence, Kans., 1908. . 45 

 Supplementary report of an experiment made at Bowling Green, Ky., 



1907 46 



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