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Eight crops were grown in greenhouse experiments on limed and fertilized sphagnum peat soil treated with various rates of borax. All crops, including beans and potatoes which have low requirements, gave marked response to borax when none was present in the chemicals used for correcting soil acidity. Commercial lime apparently provided sufficient boron as an impurity to reduce the response considerably.Boron levels accumulating from successive applications were toxic to sensitive crops like oats and beans, only when heavy rates had been applied. With cabbage, a tolerant crop, the heaviest rate of 600 pounds/acre, applied over a 4-year period, gave no indication of toxicity.Boron deficiency was alleviated and maximum crop yields were obtained at water-soluble soil boron concentrations ranging from 1.5 p.p.m. for beans to 2.8 p.p.m. for lettuce. Toxicity symptoms were apparent at soil levels extending from 4.8 p.p.m. for oats to > 11 p.p.m. for cabbage.Minimum sufficiency concentrations in the plant tissue varied from 12 p.p.m. in beans and potatoes to 32 p.p.m. in spinach. The lowest values associated with toxicity extended from 105 p.p.m. in oats to > 200 p.p.m. in cabbage.

Carrots, Daucus carota L., were grown on both sphagnum peat and mineral soils from 1969 to 1972 inclusive. Fertilizer treatments consisted of three rates of N, of P and of K applied in all possible combinations.In practically every instance rates of N, P and K applied to sphagnum peat were reflected in the levels of these nutrients found in carrot leaves. This was not the case with mineral soils.On sphagnum peat there were eight opportunities, and on mineral soils seven, for each of the three applied nutrients to influence yields. On peat N increased yields in three instances, P in one and K in five. On mineral soils N decreased yields in two instances, P decreased them in one and increased them in one while K had no effect.The results suggest that on sphagnum peat carrots may require N, P and K up to 250, 50 and 150 kg/ha respectively whereas on mineral soils maximum rates would be 25, 25 and 50 kg/ha. or transmitted in any form or by any means, electronic or mechanical, including photocopying, microfilming, and recording, or by any information storage and retrieval system, without permission in writing from the publisher.

Five crops, carrot, onion, spinach, cauliflower and lettuce (Daucus carota L., var. sativa D. C.), (Allium cepa L.), (Spinacia oleracea L.), (Brassica oleracea, var. botrytis L.), (Lactuca sativa, var. capitata L.).] were grown successively in pails of virgin sphagnum peat soil receiving 6 rates of Cu and 5 of Mo in a replicated factorial experiment. The soil was limed to slightly above pH 5.0 and other nutrients were added as necessary. Significant yield responses to Cu applications were obtained with all crops, because of deficiencies on the untreatnts. soil and of toxicities on the plots receiving very high treatments. Molybdenum treatments also encompassed the range from deficiency to toxicity with all crops except spinach. Except for Cu in onion, analyses for Cu and Mo in aboveground plant tissue after harvests were closely related to treatments. The range in Mo content was 0.2–7, 0.4–42, 0.3–140, 1.8–1,140, and 0.5–280 ppm. for carrot, onion, spinach, cauliflower and lettuce, respectively. The range in Cu content for the same crops was 3.4–14, 6.5–11, 1.6–64, 2.2–17, and 3.1–13 ppm. A mutual antagonism between Cu and Mo was appaarent whereby the application of one element to the soil significantly affected the content of the other in the plant (except for onion). This was related to a significant yield interaction with cauliflower and to nonsignificant trends with the other crops. In general, the antagonism was exemplified in one or both of the following ways: (i) Toxicities of one nutrient were alleviated by applications of the other; and (ii) deficiencies of one nutrient were aggravated by excesses of the other.

Black plastic and sawdust mulches were applied to ridged and flat rows it a 2-year (1956-1957) study of their effeci on romato culcure. Records were t;ken of soil temperatuie and moisrure 1e'els, ripe fruit to August 31' and total crop (ripe and green fruit).The highest early i'ield u'as obtained from the unmulched and sawdust plots bur"the hcai.iesr'total f.ield came from,.rhe blacl< plastic plots. Highest ioil temperature and iorveit moisture readings_ were recorded und,er the black plastic, and. lorvest so I temperature and highest moisture under the sawdust.The earliest ripe fruits came from the flat rows' but th.e-total. crop was significantly higher on the ridge rorvs. There was no significalt interactiol for mulches and row type.