Winter wheat [Trificum aestivum(L.) em Thell. cv. Stephens] seedling growth and development were observed for plants grown in a greenhouse in 1.65 × 10 ‒4m3or 3.40 × 10 ‒3m3of potting soil to determine the effect of restricted root development on plant growth with adequate water and minerals supplied. Plants grown in a smaller volume of soil were significantly reduced in size as measured by number of leaves and culms/plant, main stem height, and final dry weight/plant. These results suggest that confining roots to a small volume of rooting medium will in itself limit coordination of plant growth in an otherwise suitable environment.

No abstract

Vegetation removal in early spring by clipping or by grazing was studied in six fields of semidwarf winter wheat (Triticum aestivum L.). Varieties grown were ‘Games’ or ‘Nugaines’ which are common soft white wheat having exceptional stooling and yielding ability. Grazing was started as soon as livestock could obtain adequate feed from the early spring growth and stopped prior to the time the upper node could be removed by grazing. Clipping treatments were applied during this period. Removing vegetation either by clipping or by grazing significantly decreased grain yields. Plant height, heads per square meter, and straw production were reduced by vegetation removal. Increasing the amount of vegetation removed, extending the length of time vegetation was removed, or delaying the starting of clipping or grazing increased the reduction in each of these characters. Clipping simulated grazing of the early spring growth within the limits of humans to estimate when and how much forage to remove to duplicate grazing.

Synopsis Seed yields of Kentucky bluegrass and red fescue were increased significantly by complete removal of post‐harvest residue prior to initiation of fall growth. Burning the residue after the initiation of fall growth significantly reduced seed yields. A positive interaction between residue removal and fertilizer application was measured.

Synopsis Sulfur‐deficient alfalfa harvested at the early bloom stage contained less than 0.22% S and had a N:S ratio greater than 11.

Synopsis Sulfur fertilization increased the sulfur and nitrogen content and yield of alfalfa herbage. Percent sulfur was highest in the young growth and declined at a near linear rate for both deficient and nondeficient plants. The use of a critical level of sulfur in alfalfa herbage needs to be associated with a definite stage of growth. The nitrogen to sulfur ratio in the herbage was nearly constant at all stages of growth and was much narrower in the nondeficient than in sulfur‐deficient herbage.

Synopsis Application of 5 pounds of Zn per acre broadcast and plowed under before planting increased early growth and grain yield. Other methods of application were less effective. Greater rates of application increased Zn concentration in young and nearly mature corn. Small amounts of N banded with ZnSO4 enhanced the effectiveness of ZnSO4. Yields of corn grain were related to Zn concentration of the index leaf.

SYNOPSISStudies of irrigated corn on old rotation plots on very fine sandy loam had the. following general results: In year of N fertilizer application, increased yields were influenced by season and soil productivity as well as by time and rate of application. Time of application had little influence on yield on -lo.w productivity soil. Marked yield increases from residual N were also influenced by the above factors. Fertilizer N was more efficient during year of application when applied before plowing, at planting time, or side-dressed when corn was 6 to 12 in. high than when side-dressed when corn was 20 to 36 in. high. Yield increases from residual nitrogen increased with delay in time of application.