Germination and emergence of sudangrass (Sorghum sudanense Stapf ‘Piper’), barley (Hordeum vulgare L. ‘Numar’), radish (Raphanus sativus L. ‘Cherry Belle’), and spinach (Spinacea oleracea L. ‘Bloomsdale’) in a glasshouse were investigated using a Chino loam soil where various amounts (0, 5, 10, 15, and 20% dry manure by weight) of dairy manure were added. The degree of germination injury depended on the crop species and rate of application or the salt and N inputs. The crop sensitivity to salt or NH3 were as follows: barley < sudangrass and spinach < radish. Barley and sudangrass were more tolerant to salt or NH3 than spinach and radish. Barley germination data from treatments which had NaCl added to the soil extracts to obtain the same osmotic potential as those treated with urine, urea, or manure suggest that the germination injury was not salt specific and that other compounds such as NH3 were also contributing factors.Germination injury can be minimized by planting several days after soil application of large amounts of dairy or feedlot manure to allow volatilization of a significant quantity of NH3 or after adequate preirrigation, or both.

In areas of high concentrations of domestic animals, such as the Chino‐Corona Basin in southern California, there is a tendency to use large amounts of manures on adjacent croplands. In these situations, there is a need to know the upper safe limits of manure use for protection of animals from excess nitrate (NO‐3) in forage and for the protection of groundwaters from NO‐3 and soluble salts. A field trial on the Moreno Farm of the Univ. of California, Riverside was conducted to respond to these needs. This paper presents the results of this experiment relative to the upper safe limits for NO‐3 in barley and sudangrass forages used by the dairy industry. Barley grown in the winter of 1972–73 and sudangrass grown in the summer of 1973 were analyzed for NO‐3. These crops represented the third year of an experiment with two manures (dry dairy corral manure and liquid manure from a feedyard) and two irrigation treatments (ET and 1.33 ET) on a Hanford sandy loam. Nitrate concentrations in barley decreased progressively as the crop grew, were higher with liquid than with dry manure, and were not affected by irrigation level. The NO‐3 concentrations in sudangrass generally increased as the crop grew until just prior to emergence of flower heads from the boot and then decreased, were higher with liquid than with dry manure, and were higher with the lower water level. Based on the NO‐3 content of sudangrass the safe annual rate of liquid manure, which had 4.8% N on a dry weight basis, for the particular management system in which half of the manure was applied at the time of planting of barley in the fall and the other half at time of planting of the sudangrass, was about 8.6 metric tons of dry weight/ha/year. The safe limit of dry manure, which contained 1.8% N on a dry weight basis, for the same croppingmanagement system was about 29 metric tons of dry matter/ha/year.

Soil temperature and moisture are important in cattle waste management. The effects of these two variables on N losses from different rates of applied manure were studied under greenhouse conditions at two soil moisture (60 and 90% of water saturation percentage, WSP) and two soil temperature (10 and 25C) levels.The manure rate did not have a significant effect on the percentage of loss of applied N. At 10C, the average losses of applied N were 26 and 39%, respectively, for the 60 and 90% moisture levels. Higher losses of 40 and 45% were obtained for the 60 and 90% levels, respectively, at 25C. Results suggest that these losses occurred largely through volatilization of NH3. Under conditions where significant nitrification occurred, there were greater concentrations of electrolytes associated with reduction in pH indicating that leaching of NO3− cannot be divorced from soluble salts in manure disposal areas.With N losses approaching 50% of the applied N, large quantities of N are being volatilized to the atmosphere over large and concentrated dairy and feedlot areas.

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