OCR Text |
Show The letter »A» indicate* alkali and solnble salts, with numbers indicating intensity of occurrence. Areas shown 1 A are free from harmful Quantities of alkali{ 2 A indicates areas where salts or alkali would be slightly detrimental to crops; 3 A indicates areas where salts or alkali would be Moderately detrimental; k A, areas temporarily non-irrigable because of salts or alkali; and 6 A, areas where most crops will not grow because of salts or ai kai 1 and where reclamation is not feasible. Topography is shown by the letter T" preceded by numbers, as follows! 1 T, first class topography; 2 T, second class topography; 3 T, third class topography; k T, fourth clasa topography, temporarily non-irrigable; and 6 T, sixth class topography, non-irrigable. Areas which are temporarily non-irrigable because of the need of drainage facilities are shown by the symbol 4 D. The Tarious classifications of land, baaed upon soil characteristics, topography, alkali and drainage, are described in the following paragraphs. DESCRIPTION OF LAND CLASSIFICATIONS First Class Land - Well Suited to Irri£ation First class land is that having soil that is deep, easy to cultivate, has good drainage, is free from harmful accumulations of salts and alkali, is not excessively porous or leachy, has good water holding capacity and is free from hardpan or impervious clay. The topographic features are such that only » moderate expense would be required to prepare the land for irrigation. When timbered areas of this class are to be developed, cost of clearing the land must be considered. Timber cover has been indicated on the maps by the use of the symbol "Tim", in addition to the symbols for land classification. First class land is well adapted to the production of practically all crops that are generally grown in this region. - 2 - |
Source |
Original book: [State of Arizona, complainant v. State of California, Palo Verde Irrigation District, Coachella Valley County Water District, Metropolitan Water District of Southern California, City of Los Angeles, California, City of San Diego, California, and County of San Diego, California, defendants, United States of America, State of Nevada, State of New Mexico, State of Utah, interveners] : |