In southern Iowa where the Grundy silt loam is one of the principal upland soil types, less than 1 percent of the total acreage of cropped land is devoted to the production of alfalfa. This low acreage in alfalfa is due to the fact that the soils there are generally acid in reaction and are not suited to the production of alfalfa until the acidity is corrected by liming. Furthermore, these acid soils are deficient in the alfalfa root-nodule bacteria which must be introduced into the soil after liming if the best results are to be obtained.

In this bulletin a report is given of experiments conducted on Grundy silt loam to determine the effects of lime and inoculation, each alone and in combination with manure and super-phosphate, on the yield and quality of alfalfa produced. Quarry-run limestone was applied to different plots in varying amounts; on other plots limestone of different degrees of fineness, and hydrated lime, were applied. Inoculated seed was used on one-half of each plot, and seed without inoculation was seeded on the other half.