Many agricultural workers feel that 10-34-0 is a superior fertilizer for alfalfa since it is thought to move deeper in the soil with irrigation, be more available to the plant, and result in higher yields at equivalent rates compared to 11-52- 0. We found in our study with 24 cuttings over 3 years that alfalfa yields were similar if fertilized with 10-34-0 or 11-52-0 at equivalent rates. Total plant P was not affected by P fertilizer form or method of application. Broadcast 11- 52-0 resulted in higher soil P levels than water-run 10-34-0 and moved deeper in the soil profile. Broadcast 11-52-0 and water-run 10-34-0 appear to be equally effective P fertilizers for alfalfa in the irrigated southwest.

Six treatments containing carbohydrates and/or fertilizer were applied to alfalfa shortly after cutting in July 2002 to help ascertain if foliar applied carbohydrates would be helpful in overcoming summer slump of alfalfa hay production in the desert southwest. No significant differences were noted for any treatment for yield or quality when compared with the untreated check, although a trend for increased quality from treatments was noted. Highest yielding treatment was DC34, which increased tonnage by less than 0.1 tons/acre compared with the untreated check. DC34 was also among the highest in alfalfa quality. Alfalfa treated with Amaze® had the highest quality, but no affect on yield. As applications were made when little green foliage was available, most of the applied treatments did not actually contact green tissue but brown/dessicated alfalfa tissue or bare soil. Applying treatments during the regrowth cycle when more foliage is available may result in improved results as suggested by the trends noted from this experiment's treatments, however further testing will be necessary to verify such results.

Three plant growth regulators (two for growth enhancement, one for growth inhibition) were applied to several consecutive cuttings of alfalfa during the period of May-August in the Blythe, CA, area. All treatments resulted in reduced tonnage compared to the untreated check, although application of prohexadione calcium (active ingredient in the growth inhibition plant growth regulator) did result in increase in alfalfa quality when applied in May. Subsequent applications during the summer of this material did not result in a quality class increase for alfalfa hay production. Treatments of growth enhancement chemistries did result in less tonnage, however, data indicate that this reduction may be due to nutritional needs of alfalfa not being supplied during periods of increased growth. Supplemental nutrition along with the growth enhancement chemistries has not been tested to determine resulting alfalfa yields.