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appears to offer no real risk in degrading quality of the unpruned portion of the stem as a cost for
increasing the quality of the pruned stem.
624. Turner, J. 1982. The mass flow component of nutrient supply in three western Washington forest
types. Acta-Oecologica,-Oecologia-Plantarum 3(4): 323-329.
Keywords: fertilization
soil properties
growth
tree physiology
Abstract: [See FA 37, 7318; 38, 5185; 39, 1857; 41, 3566; 44, 4913] The mass flow
component of nutrient uptake, defined as the product of bulk soil sol. concn. and water uptake
was calculated for a series of forest stands from previously published data. Stands were of
Douglas fir of varying ages and nutrient status (both undisturbed and fertilized), red alder (Alnus
rubra), Pacific silver fir (Abies amabilis) and beech (Fagus sylvatica). Uptake of N, P, K, and Mg
increased, and Ca uptake remained stable as stands matured; the proportion of nutrient uptake
fulfilled by mass flow tended to increase with stand age. Fertilizer application gave various
results related to changes in soil sol. nutrient concn. and tree growth. The stands of red alder and
silver fir showed variable patterns between nutrients and these are discussed in relation to soil
nutrients, productivity and previously unpublished data.
625. Turner, J., D.W. Johnson and M.J. Lambert. 1980. Sulphur cycling in a Douglas-fir forest and its
modification by nitrogen application. Acta-Oecologica,-Oecologia-Plantarum 1(1): 27-35.
Keywords: fertilization
soil properties
Abstract: [See FA 39, 1857] In a study of a 42-yr-old nitrogen-deficient stand in
Washington State, subject to acid rain and elevated inputs of S, excess S was found to be stored
and cycled as SO4. A nitrogen (urea) fertilizer experiment reported previously resulted in the
incorporation of foliar SO4 into organic S and a reduction in concn. of litterfall SO4. Nitrogen
stress induced in the same experiment by addition of carbohydrate (sucrose and sawdust) to the
forest floor resulted in greater return of SO4 via litterfall.
626. Turner, J., M.J. Lambert and S.P. Gessel. 1988. Nitrogen requirements in young Douglas-fir of
the Pacific North-west. Fertilizer-Research 15(2): 173-179.
Keywords: fertilization
growth
tree physiology
Abstract: A series of fourteen Pacific North-west Douglas-fir installations, ranging in age
from 6 to 26 years were analysed with respect to site factors, foliage nutrients, and growth
response to applied fertilizer. Unfertilized basal area increment ranged from 1.2 to 3.1
msuperscript 2 ha-1yr-1 with no apparent relationship with soil, stand age or site index. Basal
area increment was correlated with foliage N and a critical level of N was calculated as 1.7%.
Applications of 220 kg N ha-1 as urea increased growth between 0 and 95% of the unfertilized
basal area growth, with an average of 24.9%. Response could be predicted from foliage N and
unfertilized basal area increment. When the same relationships were applied to previously older