A 2-year field study was conducted to determine the possibility of supplementing soil and symbiotically-fixed nitrogen of soybeans with nitrogen fertilizer. In 1947, during a hot dry growing season marked responses were obtained from added nitrogen. The number of nodules per plant decreased 80 to 90%, there were appreciable increases in seed yields, nitrogen content of the seed increased, and oil content decreased. In 1949, with adequate rainfall, moderate temperatures, and 30 to 40 days additional growing season there was little to no response to added nitrogen. The number of nodules per plant on the untreated plots was larger than in 1947, and the largest application of ammonium nitrate resulted in only a 35% decrease in number of nodules. The yield of seed increased very little, and no change occurred in the nitrogen and oil contents of the seed. A comparison of three dates of side-dressing with plow-down treatments indicated that the most effective utilization occurred with plow-down applications. This experiment helps explain some of the variation in response of soybeans to nitrogen fertilizers. Rainfall and temperature conditions during the growing season apparently have a direct influence on the sufficiency of symbiotically-fixed nitrogen for maximum yields, thus indirectly influencing the response to added nitrogen.

Year-long records of soil moisture are reported for three forest soils of southeastern Ohio. Sustained maximum and minimum soil moisture levels are in close agreement with the moisture equivalent and permanent-wilting percentage as determined in the laboratory and greenhouse. Data on the relationship of readily available water to soil texture are presented for soils of the Muskingum-Wellston-Zanesville association. Moisture losses from the soil through transpiration and evaporation during the 1951 growing season amounted to 13, 12, and 23 inches for the soils examined. The greatest loss was from Zaleski loam on a lower slope, and the smaller losses were from Wellston silt loam and Muskingum loam found on a ridge and upper slope. It is believed that moisture losses through evaporation from the soil proper are small and that the losses reported closely approximate the amount of moisture extracted for transpiration. The growth rate of white oak (Quercus alba L.) is considerably more rapid on the Zaleski loam than on the other soils. Because utilization of water is complete on the moist sites, it appears that the oak forests are capable of transpiring more water than is ordinarily available. In years of average precipitation, as much as 25 inches of water might be used in transpiration from trees and evaporation from all soil surfaces in the forest during the growing season. The remaining 15 inches of the average 40-inch rainfall may be accounted for by evaporation, runoff, and deep seepage during the rest of the year.

Three (sometimes two) applications of 1 lb DDT per acre at fortnightly intervals prevented infestation of tops during most of the growing period of the spring-planted crop and reduced the likelihood of tuber infestation. DDT was more effective as a spray than a dust; sprays produced increases of up to 17% in number and 43% in weight of table quality tubers. The proper integration of DDT spraying and hilling is essential for Gnorimoschema control, as each fulfils a separate but complementary role in ensuring the maximum production of sound tubers.

The value of milk in the National dietary cannot be too strongly emphasized; no single food is nutritionally complete but milk must be regarded as a product which most nearly attains the ideal. There is a growing public awareness of the role of milk as a "protective'• foodstuff and as a supplement to the normal carbohydrate-rich diet of the average New Zealand household. In the past, milk quality has been synonomous with keeping quality and the bacteriological status of the milk passed on to the consumer, but more recently- through the medium of the press, Government departments and local bodies, the concept of nutritive status has started to assume the importance it warrants; even so, to the public in general, the value of the various milk components is only vaguely appreciated; New Zealand's liquid milk supply has been the Cinderella of the Dairy Industry for too many years since statistically it accounts for only 9% of the Dominion's total butterfat production.

A decreased availability of plant food throughout the growing season has been observed for some stubble mulch practices. To determine if the microflora were involved as a possible factor in this plant food availability difference, comparative data were obtained from double-cut and turnplow soil samples. Under the conditions of this investigation the following microbiological factors may be related to the plant food tie-up problems: (a) The environmental conditions of better oxygen supply and more organic matter in the 0–6 inch horizon seem to favor the stimulation of the soil fungi in the mulch plots. This group of soil microorganisms might cause a temporary loss of nitrate-nitrogen as a result of protein synthesis by the mold cells. (b) Biochemical nitrification as determined with the perfusion apparatus of Lees and Quastel showed slightly lower amounts of nitrate-nitrogen formed from the mulch than from the turnplow samples. In addition, the soil pH should be considered as an environmental factor which may have considerable influence on the activity of the soil population. It is believed that these factors might be temporarily involved in the plant food tieup problems found to be associated with stubble mulch tillage practices at Virginia Polytechnic Institute.

Crop rotations and soil-management practices on a random sample of mixed crop and livestock properties on the North- Western Slope were discussed in the last issue of this journal. The survey on which the latter article was based was carried out in March, April and May, 1952, and seventy-six farmers were visited in the shires of Peel, Liverpool Plains, Macintyre and Yallaroi. As the survey was concerned mainly with practices on wheat farms, the sample was drawn from important wheat-growing districts in different parts of the North Western Slope. The first article included an analysis of the influence of the size of farms and different soil types on the cropping practices adopted throughout the area. In order to compare the practices of holdings of different size groups, farms of 600 acres, or less, arable, and of a total area not exceeding 1,000 acres, were classed as "small" farms and the remainder as "large" farms. A significant relation was found to exist between the crop rotations followed on farms in these two size-groups, ninety per cent. of the small holdings having a rotation of one-year in-two, or shorter, compared with fifty-five per cent. for the large properties. It was also found that higher incomes in recent years, largely due to higher wool prices, have enabled farmers, especially those on small holdings, to introduce wider crop rotations and other soil conserving practices.

A large proportion of the potassium absorbed by plants growing on Ramona loam is obtained from the nonexchangeable form. The nonexchangeable potassium may possibly be released to the solution phase before being absorbed by plant roots. This investigation concerns the release of fixed potassium from Ramona loam through the action of various acids and salts. The soil contains 20,000 ppm of potassium of which 78 ppm is exchangeable to neutral, normal ammonium acetate. Rye plants grown by the Neubauer technique removed in addition 112 ppm of nonexchangeable K from the soil. Water saturated with CO₂ at pH 4.0 leached through the soil for 50 days removed only 39 ppm of nonexchangeable K. It was noted that equal volumes of CO₂ saturated water which passed through the soil removed the same amount of K regardless of the rate of leaching or thickness of the soil column. The final concentration of potassium in the CO₂ saturated water leachates was 0.1 ppm K. Extraction and leaching studies with dilute acid solutions varying in pH from 1 to 7 revealed a correlation between pH and the amount of K replaced from the soil. Potassium replaced with 0.1 N acid solutions with pH ranges between 3 and 7 was mostly from the exchangeable form, whereas that replaced at pH values below 3 included a large proportion of the non-exchangeable form. A comparison of leaching and extraction studies demonstrates that for equal volumes and pH values the extraction method is more efficient in releasing nonexchangeable K than the leaching method. This holds even for water saturated with CO₂. In extractions with various chloride salts, ammonium acetate, and hydrochloric acid, it was found that all ions except ammonium replaced nonexchangeable K from the soil. The ions in descending order of effectiveness of replacement of K from the soil are H⁺ > Na⁺ > Li⁺ > Ca⁺⁺ > Mg⁺⁺ > NH₄⁺.