Thinning and nitrogen fertilization effects on sapwood development and relationships of foliage quantity to sapwood area and basal area in Douglas-fir

1983 ◽  
Vol 13 (3) ◽  
pp. 384-389 ◽  
Author(s):  
H. Brix ◽  
A. K. Mitchell
Keyword(s):  
Nitrogen Fertilization ◽  
Basal Area ◽  
Douglas Fir ◽  
Annual Rings ◽  
Cross Sectional ◽  
Sapwood Area ◽  
Breast Height ◽  
Linear Relationships ◽  
Regression Slopes ◽  
Fertilization Effects

A 24-year-old Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) stand was treated with various levels and combinations of nitrogen fertilization and thinning. Over a period of 5–9 years after treatments, trees were sampled to determine effects on foliage quantity and sapwood characteristics at different stem heights together with their relationships. Sapwood width remained relatively constant up the stem where heartwood was present, but the number of annual rings it contained decreased with height. The sapwood width at breast height (bh) increased with stem diameter; treatments had little effect on percent sapwood at bh. The ratio of foliage mass to sapwood cross-sectional area changed for different portions of the crown and was lower when based on sapwood area at bh than at base of live crown. Significant linear relationships of foliage mass and area to sapwood area at bh were found, but relationships of foliage to basal area (bh) were just as close for all treatments; treatments significantly affected these relationships with control trees having the lowest regression slopes.

Leaf area – sapwood area relationships in adjacent young Douglas-fir stands with different early growth rates

1987 ◽  
Vol 17 (2) ◽  
pp. 174-180 ◽  
Author(s):  
M. A. Espinosa Bancalari ◽  
D. A. Perry ◽  
John D. Marshall
Keyword(s):  
Leaf Area ◽  
Growth Rates ◽  
Ring Width ◽  
Basal Area ◽  
Early Growth ◽  
Douglas Fir ◽  
Sapwood Area ◽  
Breast Height ◽  
Pipe Model ◽  
The Relationship

The relationship between foliage area and sapwood basal area was studied in three adjacent 22-year-old Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) stands that differed in early growth rates. Sapwood width was fairly constant for most of the stem above the stump, but the number of annual rings in the sapwood decreased gradually with height. Sapwood area also decreased with increasing height in the tree, the stands differing significantly only at breast height. The proportion of heartwood from stump to near the base of the crown was significantly higher for the stand of fastest early growth. Ratios of leaf area to sapwood area were significantly higher for that stand and varied in every stem section, the ratio lower at breast height than at the base of the live crown. At the base of the crown, the ratio of leaf area to sapwood area was 1.33 and 1.57 times greater in the fast-growing stand than in the intermediate- and slow-growing stands, respectively. Leaf area was as closely related to dbh as to sapwood area at breast height. Sapwood area at the crown base was more accurate than sapwood area at breast height for predicting leaf area in the fast stand and was equally accurate in the other two stands. Ratios of leaf area to sapwood area correlated positively with sapwood ring width. However, because sapwood ring width also correlated closely with sapwood area, it did not improve predictive equations. The results suggest that the "pipe model" theory must be modified to account for the internal structure of the "pipe" and that caution should be exercised when using published leaf area to sapwood area ratios.

Response of Nine-Year-Old Plantation Sweetgum to Nitrogen Fertilization in Mississippi

1992 ◽  
Vol 16 (3) ◽  
pp. 146-150
Author(s):  
L. E. Nelson ◽  
G. L. Switzer
Keyword(s):  
Nitrogen Fertilization ◽  
Basal Area ◽  
Woody Biomass ◽  
Growing Season ◽  
Maximum Growth ◽  
Liquidambar Styraciflua ◽  
Stem Volume ◽  
Breast Height ◽  
Seed Sources ◽  
N Rates

Abstract Nine-year-old planted sweetgum (Liquidambar styraciflua L.) consisting of four half-sib seed sources were refertilized with nitrogen in 1981 at the beginning of the tenth field-growing season. Increases in periodic annual height, diameter at breast height, basal area, stem volume (ob),and woody biomass increments of all four half-sib seed sources from applied nitrogen were observed during the 9 years following application. Periodic annual stem volume (ob) increments averaged over all half-sib seed sources were 120, 152, 192, and 266 ft³/ac/yr for the 0, 89, 178, and356 lb/ac N rates, respectively. The half-sib seed sources from alluvial sites were superior to those from upland sites in terms of productivity and response to N. The response of all half-sibs to N was immediate, occurring during the year of application; however, the increased growth ratesdue to N persisted for only 3 years. This suggests that on responsive sites, applications of N may be necessary every fourth year to maintain maximum growth rates. South. J. Appl. For. 16(3):146-150.

Growth Response to Fertilization in Young Douglas-Fir Stands

1989 ◽  
Vol 4 (4) ◽  
pp. 116-119 ◽  
Author(s):  
Linda S. Heath ◽  
H. N. Chappell
Keyword(s):  
Pseudotsuga Menziesii ◽  
Growth Response ◽  
Volume Growth ◽  
Basal Area ◽  
Site Index ◽  
Douglas Fir ◽  
Intermediate Region ◽  
Fertilizer Response ◽  
Breast Height ◽  
Inverse Effect

Abstract Response surface methodology was used to estimate six-year volume growth response to 1 application of 200 lb nitrogen per acre in unthinned and thinned Douglas-fir (Pseudotsuga menziesii) stands of breast height age (bha) 25 years or less. Regional mean fertilizer response was 16% in unthinned stands and 20% in thinned stands. Site index had an increasingly inverse effect on response as basal area increased in both unthinned and thinned stands. Response varied little over site index in regions of low basal area, decreased moderately as site index increased in the intermediate region, and decreased rapidly in the high basal area region. West. J. Appl. For. 4(4):116-119, October 1989.

Relationships between foliar number and the cross-sectional areas of sapwood and annual rings in red oak (Quercusrubra) crowns

1993 ◽  
Vol 23 (7) ◽  
pp. 1245-1251 ◽  
Author(s):  
D. Andrew White
Keyword(s):  
Annual Ring ◽  
Red Oak ◽  
Annual Rings ◽  
Cross Sectional ◽  
Sapwood Area ◽  
Functional Relationships ◽  
Close Relationship ◽  
Number Of Leaves ◽  
The Cross ◽  
Lower Correlation

Correlations and functional relationships of sapwood and annual ring cross-sectional areas versus the number of leaves supported inside the live crowns of red oak (Quercusrubra L.) were found, based on analyses of six 20- to 25-year-old oaks from monocultures in southern Ontario. Differences in numbers of leaves supported across intervals inside the crowns were compared, using correlation analyses, with the corresponding differences in conductive sapwood (outer two annual rings) cross-sectional areas, and the current and previous year's annual ring's cross-sectional areas. These analyses showed that the current year's annual ring area had a lower correlation with number of current leaves supported (R = 0.918, P < 0.0001) than did the previous year's annual ring area (R = 0.953, P < 0.0001) or the conductive sapwood area (R = 0.939, P < 0.0001). Functional relationships between foliar numbers supported and sapwood and annual ring cross-sectional areas inside the live crowns were found with regression analysis. The previous year's ring area (PRA) had a more linear relationship to leaf counts (FQ) than did conductive sapwood area and current annual ring area. FQ = 815.6 leaves/cm2 × PRA1.14 − 137.9. The close relationship between current foliage and previous annual ring area may reflect a developmental link between foliar primordia, which will become the following year's foliage, and the cross-sectional area of the supporting xylem.

Tree vigor and stand growth of Douglas-fir as influenced by laminated root rot

1985 ◽  
Vol 15 (5) ◽  
pp. 985-988 ◽  
Author(s):  
Ram Oren ◽  
Walter G. Thies ◽  
Richard H. Waring
Keyword(s):  
Leaf Area ◽  
Root Rot ◽  
Basal Area ◽  
Douglas Fir ◽  
Basal Area Increment ◽  
Sapwood Area ◽  
Stand Growth ◽  
Area Growth ◽  
The Impact ◽  
Stand Basal Area

Total stand sapwood basal area, a measure of competing canopy leaf area, was reduced 30% by laminated root rot induced by Phellinusweirii (Murr.) Gilb. in a heavily infected 40-year-old coastal stand of Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) compared with that of a similar uninfected stand. Annual basal area increment per unit of sapwood area, an index of tree vigor, was expected to increase in uninfected trees in the infected stand as surrounding trees died from root rot; vigor of the uninfected trees did increase by an average of 30%, offsetting the reduction in canopy leaf area. This increase, although less than might be expected in an evenly spaced thinned stand, was sufficient to maintain stand basal area growth at levels similar to those of unthinned forests. These findings indicate that increased growth by residual trees must be taken into account when the impact of disease-induced mortality on stand production is assessed.

Bulldozing stumps and nitrogen fertilization affect growth of Douglas-fir seedlings

1988 ◽  
Vol 18 (6) ◽  
pp. 803-806 ◽  
Author(s):  
W. G. Thies ◽  
E. E. Nelson
Keyword(s):  
Ammonium Nitrate ◽  
Nitrogen Fertilization ◽  
Growing Season ◽  
Douglas Fir ◽  
Olympic Peninsula ◽  
Diameter At Breast Height ◽  
Clear Cut ◽  
Breast Height ◽  
Growing Seasons ◽  
Growth Of Seedlings

Eight treatments involving stump removal by bulldozing in combination with nitrogen fertilization were applied to 0.04-ha circular plots in a clear-cut on the Olympic Peninsula, Washington. Treatments included stump removal (either all stumps removed or the plot left undisturbed) and broadcast fertilization with ammonium nitrate (0, 336, 672, or 1345 kg N ha−1). Diameter at breast height and height of Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) seedlings, planted several months after treatment, were recorded five and eight seasons after outplanting. The results showed that either bulldozing stumps from the site or fertilizing with ammonium nitrate increased growth of seedlings through their eighth growing season. After eight growing seasons, bulldozing had increased seedling height by 23% and diameter at breast height by 43%; fertilizing produced increases of 13% in height and 17% in diameter at breast height.

The role of Douglas-fir stem sapwood and heartwood in the mechanical and physiological support of crowns and development of stem form

1981 ◽  
Vol 11 (3) ◽  
pp. 459-464 ◽  
Author(s):  
James N. Long ◽  
Frederick W. Smith ◽  
David R. M. Scott
Keyword(s):  
Douglas Fir ◽  
Mechanical Support ◽  
Principal Function ◽  
Stem Form ◽  
Cross Sectional ◽  
Sapwood Area ◽  
Large Trees ◽  
Uniform Resistance ◽  
Form Development

The mechanical and physiological support of a tree's crown is the principal function of its bole. A simple model for Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) of different crown classes explains much of the observed differences in stem form development. Sapwood cross-sectional area at any height on the bole of the tree was found to be related linearly to the amount of foliage above that point; however, in large trees the sapwood area needed to supply transpiring foliage with water is insufficient to provide mechanical support. The combination of sapwood and heartwood was found to provide the stem form that would be expected to ensure uniform resistance to bending by the wind.

Equations for predicting sapwood area at crown base in southwestern Oregon Douglas-fir

1987 ◽  
Vol 17 (3) ◽  
pp. 236-241 ◽  
Author(s):  
Douglas A. Maguire ◽  
David W. Hann
Keyword(s):  
Cross Sections ◽  
Douglas Fir ◽  
Sapwood Area ◽  
Diameter At Breast Height ◽  
Total Height ◽  
Breast Height ◽  
Taper Models

Two basic taper models were analyzed for their ability to predict sapwood area at crown base. Sapwood areas were estimated on stem cross sections by measuring sapwood radii on the longest and perpendicular to longest axes and by assuming conformity to an ellipse. These data were collected on 2 to 14 points along the stems of 72 Douglas-fir trees in southwestern Oregon. Across the range in diameter at breast height, total height, and height to crown base, quadratic–quadratic segmented polynomials (T. A. Max and H. E. Burkhart. 1976. For. Sci. 25: 283–289) provided more consistent monotonie taper from breast height to crown base than F. A. Bennett and B. F. Swindel models (1972. USDA For. Serv. Res. Note SE-179). A model for predicting breast height sapwood area from only diameter at breast height, total height, and height to crown base is also presented.

Effects of disrupting stem sapwood water conduction on the water status in Douglas-fir crowns

1985 ◽  
Vol 15 (5) ◽  
pp. 982-985 ◽  
Author(s):  
H. Brix ◽  
A. K. Mitchell
Keyword(s):  
Water Potential ◽  
Water Flow ◽  
Leaf Water Potential ◽  
Water Status ◽  
Soil Water Potential ◽  
Douglas Fir ◽  
Leaf Water ◽  
Cross Sectional ◽  
Breast Height ◽  
Water Conduction

The sapwood cross-sectional area at breast height was reduced by 0 (control), 42, 69, and 100%, in 36-year-old Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) trees to study treatment effects on the water status in the crowns. Only the complete removal of breast-height sapwood affected the leaf water potential which decreased rapidly the 1st day, but then changed little for the next 38 days varying only from −2.3 to −2.6 MPa. Water use for those trees was limited to that stored above breast height, primarily in stem sapwood, and amounted to approximately 45 L. This corresponded to 6.5 mm of precipitation or 4% of potential transpiration. The finding that leaf water potential was not affected by partial sapwood reduction but rather by changes in soil water potential suggests that resistance to water flow in stems was small compared with that in other parts of the water-flow pathways of soil and trees.

Thinning and nitrogen fertilization effects on soil and tree water stress in a Douglas-fir stand

1986 ◽  
Vol 16 (6) ◽  
pp. 1334-1338 ◽  
Author(s):  
H. Brix ◽  
A. K. Mitchell
Keyword(s):  
Water Potential ◽  
Soil Water ◽  
Nitrogen Fertilization ◽  
Soil Water Potential ◽  
Early Morning ◽  
Douglas Fir ◽  
Fertilization Effect ◽  
Use Efficiency ◽  
Soil Water Conditions ◽  
Fertilization Effects

Soil and tree water potentials were studied over a 10-year period in a Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) stand that was treated when 24 years old with different thinning and nitrogen fertilization regimes. Throughout the 10-year period, thinning increased the soil water potential during the dry summer periods (July–September) by as much as 1 MPa both with and without fertilization. Fertilization effect on soil water potential was slight and only apparent in the latter part of the study in spite of large increases in leaf area (50% after 7 years) possibly because of better stomatal control of water loss. Fertilization increased water use efficiency. The favorable soil water conditions produced by thinning led to improved shoot water potential only during predawn and early morning. Removal of understory in a thinned and fertilized plot did not affect soil or shoot water potential.

Sign in / Sign up

Export Citation Format

Share Document