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UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 1038 
Contribution from the Bureau of Plant Industry 
WM. A. TAYLOR, Chief 
Washington, D. C. 
March 20, 1922 
PECAN ROSETTE 
ITS HISTOLOGY, CYTOLOGY, AND RELATION 
TO OTHER CHLOROTIC DISEASES 
By 
FREDERICK V. RAND 
Pathologist, Laboratory of Plant Pathology 
CONTENTS 
Types of Chlorotic Plant Diseases .... 1 
Chloroses Due to Soil or Atmospheric 
Conditions 2 
Infectious Chloroses 6 
Studies of Pecan Rosette 13 
Results of Previous Work 13 
External Signs of Rosette' 17 
Page 
Studies of Pecan Rosette — Continued. 
Histological and Cytological Studies . 19 
Subsidiary Experiments 30 
Probable Nature of Pecan Rosette .... 31 
Summary 36 
Literature Cited 37 
WASHINGTON 
GOVERNMENT PRINTING OFFICE 
1922 
