Thirteen field trials were conducted to test the effects of rates of N and K fertilizers and seeding dates differing by 2 weeks upon yield, percentage plump kernels, and protein content of malting barley. N fertilizer increased average grain yields on early‐seeded plots by 253, 410, and 534 kg/ha for 22.4, 44.8, and 67.2 kg N/ha, respectively. On late‐seeded plots, same rates of N increased average yields by 264, 303, and 389 kg/ha, respectively. Late seeding reduced average grain yields by 295 kg/ha. Rates of 14 and 28 kg K/ha increased average grain yields by 42 and 48 kg/ha, respectively, on early‐seeded plots and by 71 and 81 kg/ha, respectively on late‐seeded plots. N did not affect average percentage of plump kernels but 14 and 28 kg K/ha increased percentage plump barley by 1.3 and 1.7 percentage units on early‐seeded plots and by 1.8 and 2.7 percentage units on late‐seeded plots, respectively. Late seeding reduced the percentage of plump kernels by 9.8 percntage units. The average protein content of grain was 12.8, 13.1, 13.2, and 13.5% on early‐seeded plots and was 13.4, 13.6, 13.9, and 14.2%percent on late‐seeded plots for O, 22.4, 44.8, and 67.2 kg N/ha, respectively. Late seeding increased the average protein content by 0.7 percentage units. K reduced the average protein content by 0.1 percentage unit on both early and late‐seeded plots.

Total water potential of barley (Hordeum vulgare L.) leaves from plants grown under greenhouse and growth chamber conditions was divided into pressure and osmotic potential components, and their relationship to leaf relative water content was determined. Pressure potential approached zero at a water potential of about −32 bars, and a relative water content of about 65%. A change in the elasticity of leaves occurred at about 2 bars pressure potential and about −12 bars water potential. First visible wilting was observed between 75 and 80% relative water content. Transpiration decreased as leaf relative water content decreased but transpiration was independent of soil water content until about 16% (0.6 bar soil suction). First visible wilting of barley leaves was observed at soil water content between 9 and 13% (1–5 bars soil suction). Water potential and leaf relative water content decreased as the soil matric potential decreased. There was a shift to lower relative water content and water potential values as plants became older when the soil matric potential decreased.

Displacement of nitrate and 36Cl through disturbed (reconstituted horizon by horizon) and undisturbed soil profiles of Aberdeen loam and Beotia loam representing strong and moderate soil structure, respectively, were investigated. Each soil core was 30 cm in diameter and at least 80 cm high. Mean water content θ̄ of the undisturbed soil profile was greater and mean bulk density D̄b less than the corresponding values for the disturbed cores for each soil. For example, disturbance increased θ̄ by 0.07 cm3/cm3 for Beotia with a 0.01 g/cm3 decrease in D̄b; disturbing Aberdeen decreased D̄b from 1.47 to 1.30 g/cm3 but increased θ̄ only 0.03 cm3/cm3. The disturbed soils required greater throughout volume of distilled water to displace the solutes and had smaller dispersion coefficients (D) than the undisturbed soils although not even a twofold difference in D was found. For a given effluent sample, relative nitrate concentration was consistently greater than relative 36Cl concentration due to nitrification occurring within both the disturbed and undisturbed soil profiles during the 24‐week period.

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Laboratory phases of a study to evaluate the effectiveness of various long‐time management practices in maintaining fertility of Fargo clay are reported. Soil samples which had been taken at the beginning of the trial in 1913 and those taken in 1952 and 1953 were used for chemical analyses. Physical measurements were made on samples taken from 1954 to 1956. Analyses included total N, organic C, pH, cation‐exchange capacity, exchangeable cations, extractable and organic P, nitrification capacity, aggregation and aggregate stability by wet‐sieving, porosity, density, and hydraulic conductivity. Soil organic C and N declined 27% in check plots and 20% in residue or manure plots. Phosphorus‐treated plots suffered slightly greater loss than similar plots without P. Lime had no effect. C/N ratio did not change. Nitrification capacity correlated with total N content. Extractable P declined appreciably in check plots, less in residue and manure plots, and increased in P‐treated plots. Organic P losses were similar to those of organic carbon. In all plots, CEC declined slightly. pH increased slightly in nonlimed plots and moderately in limed plots. Physical measurements did not reveal any important differences in structural properties of Fargo clay that could be related to past management practices.