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Irrigation agriculture in the West 全文
1948
This publication has been prepared in the interest of a permanent irrigation agriculture. Irrigation has played an important role in the remarkable achievement by farmers in this nation in meeting wartime and postwar production goals. It may play an even greater part in our future agricultural production. The food needs of a growing population and the establishment of desirable trade relations with other nations will require the maintenance of efficient, high-level agricultural production.
显示更多 [+] 显示较少 [-]Management of forests in an eastern Kentucky area
1948
Duerr, William A. (William Allen) | Gustafson, R. O. (Rudolph Olie)
Scottish farm rents & estate expenditure
1948
The nature of an efficient agriculture in the shortleaf pine area of Mississippi
1948
Parvin, David W.
The nature of an efficient agriculture in the brown loam area of Mississippi
1948
Parvin, David W.
Inventory of major land uses in the United States 全文
1948
Reuss, L. A. (Lawrence Adkins) | Wooten, H. H. (Hugh Hill) | Marschner, F. J. (Francis Joseph)
The purpose of the present publication is to supply an account of the extent and distribution of the major agricultural land uses and a general analysis of the land use situation in the United States, showing the latest data available for both land in farms and land outside farms. The information on the acreages of land devoted to the chief purposes provides a comprehensive picture of the use of all land in the United States, trends in land use, and elements affecting use.
显示更多 [+] 显示较少 [-]The red-banded leaf roller as an apple pest in New York
1948
Harman, S. W. (Samuel Willard)
A study of variations in soil properties in an apparently uniform area and their relationship to the frequency of sampling : A thesis for M.Agr.Sc. [Master of Agricultural Science] and Honours, [Lincoln College] University of New Zealand 全文
1948
Mandal, Subodhe Chandra
The aim of the investigation conducted upon a typical representative of a major Canterbury soil type, is to indicate the nature and extent of variation in an apparently uniform field and to determine the frequency of sampling necessary for different soil properties.
显示更多 [+] 显示较少 [-]The yellow-winged locust, Gastrimargus musicus Fabr., in central Queensland 全文
1948
Common, I.F.B.
Gastrimargus musicus Fabr. is an endemic locust species with a distribution practically throughout coastal and sub-coastal Australia, where the rainfall exceeds 20 inches annually. Swarming occurs in the northern half of the continent and migrations into coastal agricultural and dairying districts occurs periodically. Coastal infestations originate in localized outbreak areas in the sub-coastal districts. In central Queensland, the Clermont-Capella area was apparently the vital source of swarms which eventually caused widespread damage, particularly to pasturage, between 1939 and 1947 from Proserpine to Mt. Larcom. The ultimate aim of control practice would be the accurate mapping of outbreak areas both in central and in northern Queensland with the object of destroying incipient swarms before mass migrations commence.
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