UNITED STATES DEPARTMENT OF AGRICULTURE 

 BULLETIN No. 815 



Contribution from the Bureau of Plant Industry 

 WM, A. TAYLOR, Chief 



Washfugton, D. C. 



PROFESSIONAL PAPER 



June 1, 1920 



CITRUS-FRUIT IMPROVEMENT 



A STUDY OF BUD VARIATION IN THE 



LISBON LEMON 



By 



A. D. SHAMEL, Physiologist, L. B. SCOTT, Nomologist, C. S. POMEROY, 

 Assistant Pomologist, and C. L. DYER, Scientific Assistant, Fruit- 

 Improvement Investigations, Office of Horticultural and 

 Pomological Investigations 



CONTENTS 



Importanoc of the Lemon Industry . 

 History of the Lisbon, Lemon Variety 

 Variability within the Variety . . . 

 Objects of the Investigations . . . 

 Plan of the Investigations .... 

 Methods of Keeping Performance Rec' 



ords 



Descriptions of the Important Strains 

 Lessons Taught by These Investigations 

 Prosentation of Data 



Page 

 Comparative Value of th^e Strains ... 62 

 The Unintentional Propagation of Unde- 

 sirable Strains 63 



The Isolation of Strains through Bud 



Selection 64 



Top'working Undesirable Lemon Trees . 64 

 Replacing Undesirable Trees in Bearing 



Orchards 67 



The Selection and Care of Bad Wood . 68 



Summary 60 



WASHINGTON 



GOVERNMENT PRINTING OFFICE 



1920 



saaiai 



