TABLE OF CONTENTS xxi 



PAGES 



associated with dry farming, 615 — Extent of dry farm- 

 ing, 616. 



CHAPTER XXXI 



The Soil Survey 718-740 



The classification of soils by survey, 617 — Factors 

 employed in classification, 618 — Texture, the soil class, 

 619 — Special properties, the soil series,. 620 — Source of 

 material, the soil group, 621 — Agency of formation, the 

 soil province, 622 — Climate, 623 — The practical classi- 

 fication of soils in the United States, 624 — The soil type 

 and soil series, 625 — The equipment for survey work, 

 626 — Procedure in the field, 627 — Collection of soil 

 samples, 628 — The accuracy and detail of the soil sur- 

 vey, 629 — The soil survey report, 630 — The soil map, 



631 — The extent of soil surveys in the United States, 



632 — Surveys by state institutions, 633 — Surveys in 

 other countries, 634 — Use of the soil survey, 635. 



