UNITED STATES DEPARTMENT OP AGRICULTURE 
BULLETIN No. 813 
Contribution from the Bureau of Plant Industry 
WM. A. TAYLOR, Chief 
Washington, D. C. 
PROFESSIONAL PAPER 
June 25, 1920 
CITRUS-FRUIT IMPROVEMENT 
A STUDY OF BUD VARIATION IN THE 
EUREKA LEMON 
By 
A. D. SHAMEL, Physiologist, L. B. SCOTT, Pomologist, C. S. POMEROY, 
Assistant Pomologist, and C. L. DYER, Scientific Assistant, Fruit- 
Improvement Investigations, Office of Horticultural 
and Pomological Investigations 
CONTENTS 
Importance of the Lemon Industry . . 
History of the Eureka 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 
Presentation of Data 
Page 
1 
3 
3 
6 
7 
Page 
Comparative Value of the Strains ... 78 
The Unintentional Propagation of Unde- 
sirable Strains 79 
The Isolation of Strains through Bud 
Selection 80 
Top-Working Undesirable Trees ... 81 
Replacing Undesirable Trees in Bearing 
Orchards 84 
The Selection and Care of Bud Wood . 85 
Summary 87 
WASHINGTON 
GOVERNMENT PRINTING OFFICE 
1920 
