Douglas fir growth and foliar nutrient responses to nitrogen and sulfur fertilization

Journal Article · · Soil Science Society of America Journal; (United States)

DOI:https://doi.org/10.2136/sssaj1990.03615995005400010041x· OSTI ID:5512408

Blake, J I ^[1]; Chappell, H N; Bennett, W S; Gessel, S P ^[2]; Webster, S R ^[3]

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1. Auburn Univ., AL (USA)
2. Univ. of Washington, Seattle (USA)
3. Lewis County Extension Office, Chehalis, WA (USA)

Nitrogen-fertilizer response in conifer stands of the Pacific Northwest has been related to soil and foliar S, and growth has occasionally been enhanced by the addition of S. In order to test the effect of soil SO{sub 4}-S concentrations on N response, five stands of Douglas fir, Pseudotsuga menziesii (Mirb.) Franco, with low to moderate quantities of SO{sub 4}-S in the mineral soil horizon were treated with N and with N plus S. Sulfate-S concentrations varied among soils from 6.0 to 19.2 mg S kg{sup {minus}1} in the surface soil and from 6.0 to 78.7 mg S kg{sup {minus}1} in the subsoil. Three treatments were applied: control, 224 kg N ha{sup {minus}1} as urea, and 224 kg N ha{sup {minus}1} plus 112 kg S ha{sup {minus}1} as a mixture of urea and (NH{sub 4}){sub 2}SO{sub 4}. Adjusted gross volume growth responses to N alone averaged {minus}1.63 to 6.26 m{sup 3}ha{sup {minus}1} yr{sup {minus}1} after 3 to 4 yr; average volume growth gains from application of N with S over application of N alone varied from 0.73 to 4.5 m{sup 3} ha{sup {minus}1} yr{sup {minus}1} at four locations. At one location, the N-alone effect was greater than that from N with S. Foliar N concentrations in the N-with-S treatments were generally higher than in the N-alone treatments. Little change in foliar-S content occurred in the N-with-S plots. Mean treatment effects were unrelated to foliar N/S, total S, or foliar SO{sub 4}-S on the controls, and the relationship between soil SO{sub 4}-S and the differential growth response between N and N with S was highly variable. Treatments were reapplied at a rate of 448 kg N ha{sup {minus}1}, 224 kg S ha{sup {minus}1}, and 9 kg B ha{sup {minus}1}. Four-year growth effects were similar to the first period except at one location where N responses appeared greatly improved by B. Prescriptions involving S will require more efficient S sources and a better assessment of S uptake and S reactions in these soils.

• OSTI ID: 5512408
• Journal Information: Soil Science Society of America Journal; (United States), Journal Name: Soil Science Society of America Journal; (United States) Vol. 54:1; ISSN SSSJD; ISSN 0361-5995
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540210* -- Environment
Terrestrial-- Basic Studies-- (1990-)
ABSORPTION
AMIDES
AMMONIUM COMPOUNDS
AMMONIUM SULFATES
BIOLOGICAL AVAILABILITY
CARBONIC ACID DERIVATIVES
CONIFERS
ELEMENTS
FIRS
FOLIAR UPTAKE
NITROGEN
NONMETALS
NUTRIENTS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXYGEN COMPOUNDS
PINOPHYTA
PLANTS
PRODUCTIVITY
ROOT ABSORPTION
SULFATES
SULFUR
SULFUR COMPOUNDS
TREES
UPTAKE
UREA