We characterized the physical transport of soil, and therefore contaminants attached to the soil, onto vegetative surfaces due to rainsplash. Soil accumulation by tomato plants (Lycopersicon esculentum) was investigated as a function of soil particle size, rainstorm characteristics, foliage height, surface area and canopy cover of the plants. No soil particles greater than 105 micron in diameter were detected on the plants. Most of the soil was splashed no higher than 40 cm above the ground surface. Linear relationships were observed for concentrations of less than 53 micron soil on vegetation and certain rainfall characteristics. Data from this study, as well as ancillary calculations, provide evidence that a significant fraction of surficial contamination of foliage may be attributed to the rainsplash mechanism.

A field study was conducted in 1977 on 238, 239Pu and 137Cs availability to zucchini squash (Curcurbita melopepo, hybrid seneca) and green bush beans (Phaseolus vulgaris, Landreths stringless) grown under home‐garden conditions in an area at Los Alamos National Laboratory used for treated radioactive liquid waste disposal. Radionuclide concentrations were measured as a function of tissue type, height above the soil, fertilization regime, and for the squash, food‐cleansing procedures. Analysis of variance procedures were used to analyze the data.Ratios of the concentration of a radionuclide in oven‐dried vegetation to dry soil ranged from 0.0004 to 0.116 for the Pu isotopes, and from 0.051 to 0.255 for 137Cs. Fertilization with cattle manure reduced the Pu concentration ratios by 30% and 137Cs by 50%. Vegetative parts sampled within 20 cm of the ground surface were contaminated about four times as much as those parts growing further from the ground surface. About 65% of the contamination was removed by washing, indicating the presence of surficial contamination. The 50‐year radiation dose commitment to humans consuming vegetables from the garden plot would be less than 0.05 mrem and would be due almost entirely to 137Cs.

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Tree growth in a 2‐year‐old sycamore (Platanus occidentalis L.) plantation in northern Alabama significantly increased over the following 4 years after three clovers and two vetches were grown with the trees. Leguminous plants were chosen to: (i) provide weed control through good ground coverage, (ii) maintain a low profile, (iii) grow during the cool season so as not to compete with the sycamore, (iv) provide cover for several years after establishment through their ability to reseed, and (v) make additional nitrogen (N) available through the fixation process. Following establishment of the leguminous plants, sycamore height and volume growth were increased as were N concentrations in sycamore foliage. Of the plants tested, Mississippi subterranean (Trifolium subteraneum L.) and crimson clovers (T. incarnatum L.) gave good ground coverage, maintained a low profile, reseeded themselves well, and increased the N content of sycamore foliage in addition to improving height and volume growth.

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