UNIVERSITY OF CALIFORNIA
AT LOS ANGELES
SOILS
SOILS
THEIR
FORMATION, PROPERTIES, COMPOSITION, AND
RELATIONS TO CLIMATE AND PLANT GROWTH
IN THE
HUMID AND ARID REGIONS
BY
E. W. HILGARD, PH.D., LL.D.,
PROFESSOR OF AGRICULTURE IN THE UNIVERSITY OF CALIFORNIA, AND DIRECTOR
OF THE CALIFORNIA AGRICULTURAL EXPERIMENT STATION
THE MACMILLAN COMPANY
LONDON: MACMILLAN & CO., LTD.
COPYRIGHT, 1906,
BY THE MACMILLAN COMPANY.
Set up and electrotyped. Published July, 1906. Reprinted
August, 1907; January, 1910; April, 19ll; September, 1912;
September, 1914; January, 1918.
Notfoooto
Berwick & Smith Co., Norwood, Mass., U.S.A.
SUMMARY OF CHAPTERS.
ORIGIN AND FORMATION OF SOILS.
Introduction.
Chapter
I. Physical Processes of Soil Formation.
II. Chemical Processes of Soil Formation.
III. Chief Soil-forming Minerals.
IV. The Various Rocks as Soil-Formers.
V. Minor Mineral Ingredients of Soils. Mineral Fertilizers.
Minerals Injurious to Agriculture.
2. PHYSICS OF SOILS.
Chapter VI. Physical Composition of Soils.
" VII. Density, Pore Space, and Volume-Weight of Soils.
" VIII. Soil and Subsoil; Causes and Processes of Differentiation; Humus.
" IX. Soil and Subsoil; Organisms Influencing Soil-Conditions. Bacteria.
" X. Soil and Subsoil in their Relations to Vegetation.
" XI. Water of Soils; Hygroscopic and Capillary Moisture.
XII. Water of Soils; Surface, Hydrostatic, and Gr…