There is an increasing trend in the area under alternate farming system both in the U.S. and around the world. At present, there are more than 26 million ha of farmland that are under organic management world wide and are expanding at a fast pace. According to USDA,more than 1 million ha of croplands and pasture lands are managed under organic farming in the U.S. and about 0.2 million ha in the New Mexico by the year 2004 (USDA,2005).From year 2001 to 2004, the area under alternate farming has shown a one order magnitude increase in the state of New Mexico.
Use of an organic fertilizer instead of a synthetic fertilizer can reduce groundwater contamination, improve microbial activity,recycle the dairy/poultry wastes and improve soil physical and chemical properties (Pang and Letey, 2000; Pudel and et al., 2002).However, noticeable changes in soil physical and chemical properties can occur only after several years of continuous amendment application. There are conflicting and divergent reported in the literature on the effects of organic farming or manure application on soil quality in the literature Haynes and Naidu, 1998). There are many researches on organic faming; however, only a few of them have been conducted on organic farms under different amounts of time. In order to understand the sustainability of the organic farming system, there is a need to assess the soil physical and chemical properties, and crop biomass and grain yields from organic farms under different amounts of time.