UNITED STATES DEPARTMENT OF AGRICULTURE 

 BULLETIN No. 697 



Contribntion from the Bureau of Plant Industry 

 WM. A. TAYLOR, Chief 



Washington, D. C. 



September 27, 1918 



CITRUS-FRUIT IMPROVEMENT: 



A STUDY OF BUD VARIATION IN THE 

 MARSH GRAPEFRUIT 



By 



A. D. SHAMEL, Physiologist in Charge, L. B. SCOTT, Pomologist, 

 and C. S. POMEROY, Assistant Pomologist, Fruit-Improvement In- 

 vestigations, Office of Horticultural and Pomological Investigations 



CONTENTS 



Introduction 



History of the Variety 



Variability within the Variety . . . . 

 Objects of the Investigations . . . . 



Plan of the Investigations 



Methods of Keeping Performance Rec- 

 ords 



Descriptions of Important Strains 



Infrequent Fruit Variations 



Seasonal Fluctuations in Production 



Pag« 



Presentation of Data 20 



Comparative Value of the Strains . . . 106 

 The Unintentional Propagation of Unde- 

 sirable Strains 108 



The Isolation of Strains through Bud 



Selection 109 



Top- Working Undesirable Trees . . . 110 



TheSelectionof Bud Wood Ill 



Summary 112 



WASEONGTON 

 GOVERNMENT PRINTING OFFICE 



1918 



