CONTENTS 



OHAPTBE ^a«^o 



I. Acreage, Distribution, Production and Valu- 

 ation .....•••• 1-13 

 II. History • 14-20 



III. Classification and Botanical Characteristics . 21-46 



Description of the Irish potato — Classification 

 of varieties — Important varieties of Iowa and 

 the Central West — Tabulation of varieties — 

 Synonyms — Description of typical varieties. 



IV. Potato Breeding 47-86 



Ideals for the potato crop — Use of score card 

 — Possibilities of improving the potato — Meth- 

 ods of improvement — Improvement of the potato 

 by selection — Running out of varieties — Ap- 

 pearance of bud sports — Improvement by hy- 

 bridization. 

 V. Climate, Soils and Rotation .... 86-112 

 Factors influencing potato culture — Heat — 

 "Water requirements — Soil texture — Available 

 plant-food — Drainage and soil air — Critical 

 period — Type, variety and strain — Diseases — 

 General types of potato-growing in the United 

 States — Soils — Rotation — Hay plants. 



VI. Manures and Fertilizers 113-132 



Fertilizer practices — Market forms of fer- 

 tilizers — Nitrogen — Phosphorus — Potassium 

 — Calcium — Sulphur — Applying fertiUzers — 

 Farm manures. 



vii 



