Some Aspects of Mineral Nutrition in Relation to Bison Flax.

That the yield and quality of oil produced by flax seed varies from year to year is a matter of common knowledge. In the absence of exact experimental data it is frequently stated that climatic factors are responsible for this variation. Since little is known about the actual process of oil synthesis by the flax plant and still less about the effect of specific environmental factors on this synthesis, it was felt that some careful studies under controlled conditions should be initiated. In these first studies the authors undertook to grow seed flax in selected nutrient solutions in an attempt to determine if there was any relation between mineral nutrition and the quality and quantity of the oil produeed from flaxseed. Fertilizers and their relation to yield of flax grown in the field have received some attention by various workers throughout America; little exists in the literature, however, relative to the growth of flax in nutrient solutions. TURNER (15) studied the effect of variations in the nitrogen supply on the ratio of top to root growth of WVinona flax. Using solutions high and low in nitrate nitrogen, he found that there was little difference in the nitrogen content of flax grown in these nutrients. He attributed the results obtained to relativelv limited use of nitrogen by flax, and coneluded that in many cases nitrogen fertilizers when applied to flax are nlot particularly beneficial. After studying the effect of the light factor on cell productioni of fiber flax grown in sand culture, ROBINSON (8) reported that the tallest growth resulted when fiber flax was grown in ten hours of light per day; flax which was exposed to light eighteen hours each day matured earliest but produeed the least vegetative growth. Thus the growth period of flax might be shortened by lengthening the photoperiod. His report showed that for fiber flax nitrogen was particularly important in early growth, and that potassium was more important as the plants matured. ADAMS (1) worked out the relation between duration of light and growth, with reference to flax grown in soil, and his findings in mlost instances bear out those of ROBINSON. In Germaniy, SELLE (11) made tests on soil acidity in relation to growth of fiber flax. He noted that the yields, based on fiber, were greatest on lime-rich soils and poorest on acid soils. Potassium, according to POWERS (7), was of the greatest importance in fertilizers for fiber flax; its presence 503