The relationship of soil fertility to decline of the sugar maple (Acer saccharum Marsh.) was studied in forest and sugarbush stands by soil studies, foliar analyses and fertilization trials. Site studies of 21 stands indicated that foliar nitrogen was low among trees and stands exhibiting crown decline symptoms and reduced growth rates. Both low and high levels of total soil N were associated with low foliar N and poor growth. Foliar Ca and Mg were closely correlated with levels in the soil.Fertilizers were applied to three stands and their influence evaluated after one growing season by visual leaf response and foliar nutrient changes. Fertilization at the rate of 224 kg of N/ha increased the low foliar N levels in the two stands where decline was present, resulting in improved foliage color and condition.The studies demonstrated that foliar N deficiencies are a critical factor in sugar maple decline. Deficiencies were corrected by fertilization during a drought period. Drought is believed by many to be the cause of decline. Both N availability and uptake may be restricted during drought periods.

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The degree of variability and its effect on accuracy of mean plot values for soil properties is an important problem needing evaluation for soil‐site studies in the Northeast. This paper discusses the variability in soils sampled in a red pine plantation site study. Two profiles were sampled by horizon on each plot. Data are presented on the following soil properties: organic matter, N, silt and clay, exchangeable Ca plus Mg, cation‐exchange capacity, and bulk density. Variability between plots was much greater than within plots. Some soil properties required a large number of samples for accurate estimation, others a small number. Variation did not differ greatly from A to B horizons.

Previous studies in New England have revealed high levels of trace metals in the forest floor of remote regions and evidence of increases in trace metal concentrations and amounts over time. In this study, forest floor profiles collected from a boreal forest in Vermont, a northern hardwood forest in New Hampshire and white pine (Pinus strobus L.) stands in Massachusetts were analyzed for Pb, Cu, Zn, Ni, Cd, and organic matter. Concentrations of Pb, Cu, Zn, Ni, and percent organic matter showed similar trends with depth in all three forests. Cadmium occurrence differed according to site. Concentrations of Pb, Cu, Zn, and Ni were greatest 2 to 4 cm below the surface of the forest floor in all three forests. As expected, percent organic matter decreased with depth in the profile. Concentration and accumulation of trace metals appear to occur in the Oe horizon.

other than conjugation. Our results indicate that conjugated materials comprise a major portion of the 14C residues present in the fish. The identity of the acid-labile conjugate was not directly determined because of inability to recover the material intact into nonaqueous media. However, in all aspects examined, the metabolite showed properties similar to the synthetic N-glucuronide of DCB and other aromatic amines (11), including a free acidic functional group, high lability under acidic conditions, and chromatographic behavior. The ease of chemical synthesis of the glucuronide conjugate may indicate that the reaction proceeds nonenzymatically in vivo.At present, virtually no quantitative information is available on the presence of dichlorobenzidine in various components