Estimating leaf area of Abieslasiocarpa across ranges of stand density and site quality

1989 ◽  
Vol 19 (7) ◽  
pp. 930-932 ◽  
Author(s):  
James N. Long ◽  
Frederick W. Smith

For a given species, differences in the relation between leaf area and sapwood cross-sectional area at breast height have been attributed to the effects of varying stand density and site quality. When leaf area of Abieslasiocarpa (Hook.) Nutt. is estimated as a function of sapwood cross-sectional area at breast height and distance from breast height to the midpoint of the crown, the apparent effects of stand density and site quality are eliminated. A comparison of these results with those for Pinuscontorta Dougl. suggests this model form should provide unbiased estimates of leaf area for a variety of species and stand conditions.

1993 ◽  
Vol 23 (8) ◽  
pp. 1704-1711 ◽  
Author(s):  
Stith T. Gower ◽  
Brent E. Haynes ◽  
Karin S. Fassnacht ◽  
Steve W. Running ◽  
E. Raymond Hunt Jr.

The objective of this study was to examine the effect of fertilization on the allometric relations for red pine (Pinusresinosa Ait.) and ponderosa pine (Pinusponderosa Dougl. ex Laws.) growing in contrasting climates. After 2 years of treatment, fertilization did not significantly affect the allometric relations between stem or branch mass and stem diameter for either species. For a similar-diameter tree, current foliage mass and area and new twig mass were significantly greater for fertilized than for control red pine and ponderosa pine. The significant increase in new foliage mass and area occurred in the upper and middle canopy for red pine and middle and lower canopy for ponderosa pine. For a similar-diameter tree, projected (one-sided) leaf area and total foliage mass were significantly greater for fertilized than for control red pine. However, leaf area and total foliage mass did not differ between similar-diameter fertilized and control ponderosa pine because fertilization decreased leaf longevity. The ratios of leaf area/sapwood cross-sectional area measured at breast height (1.37 m) were 0.14 and 0.11 for control plus fertilized red pine and ponderosa pine, respectively, and were greater (but not significantly) for fertilized than for control trees, while the ratios of leaf area/sapwood cross-sectional area measured at the base of live crown were significantly greater for fertilized than for control red pine and ponderosa pine.


1988 ◽  
Vol 18 (2) ◽  
pp. 247-250 ◽  
Author(s):  
James N. Long ◽  
Frederick W. Smith

Leaf area to sapwood area ratios for a given species are believed to vary with factors such as site quality, stand density, early stand growth rates, and crown class. Based on data from 55 mature lodgepole pine trees (Pinuscontorta var. latifolia Dougl.) from 10 plots in southeastern Wyoming, we conclude that putative density and site effects on leaf area - sapwood area relations are actually a consequence of the increase in the leaf area to sapwood area ratio with increasing sapwood area. When leaf area is estimated with a nonlinear model that includes tree size and distance to the live crown, the apparent effects of stand density and site index disappear. We consider a constant ratio of leaf area and sapwood cross-sectional area to be inappropriate for the estimation of leaf area aross the range of stand conditions included in most studies of forest ecology.


1987 ◽  
Vol 17 (3) ◽  
pp. 205-209 ◽  
Author(s):  
M. G. Keane ◽  
G. F. Weetman

To better understand the phenomenon of growth "stagnation" in high-density lodgepole pine (Pinuscontorta Dougl. ex Loud.), leaf area and its relationship with sapwood cross-sectional area were examined on both an individual tree and stand basis. Leaf areas of individual trees in a 22-year-old stand varied from 30.8 m2 (dominants in stands of low stocking) to 0.05 m2 (suppressed trees in stands of high stocking). Leaf area indices ranged from 13.4 to 2.3 m2 m−2 between low and high stocking levels, respectively. Over the same stocking range, the ratio of leaf area to sapwood cross-sectional area was reduced from 0.3 to 0.15 m2 cm−2. Intraring wood density profiles showed that ovendry density increased from 0.52 to 0.7 g cm−3 and the proportion of early wood decreased over a stocking level range of 6500–109 000 trees/ha. A reduction in hydraulic conductivity in the stems of stagnant trees, suggested by the greater proportion of narrow-diameter tracheids present, may lead to a greater resistance to water transport within the boles of trees from stagnant stands, leading to low leaf areas.


Author(s):  
V. M. Zverkovsky ◽  
O. S. Zubkova

The linear growth of forest plantations of Western Donbass’ recultivating plot №1 were studied. The established cross-sectional the area of trunks and timber reserves experimental trees.Characterized by parameters which are the volume of wood: its height, diameter at breast height and shape of the forming barrel. In diameter at breast height cross sectional area is determined and then the barrel volume is calculated. Cross sections of tree trunks are shaped like a circle or an ellipse. Knowing the volume of logs we calculated reserves of wood for trees experimental plots.The largest reserves of timber and cross-sectional area characterized planting U. pumila – 15,367 m3 and 1,9583 m2, A. platanoides – 13,328 m3 and 2,67 m2, Q. robur – 10,120 m3 and 1,452 m2, J. virginiana – 8,748 m3 and 2,106 m2. The least plantation stocks of wood characterized E. angustifolia – 1,3699 m3 and 0,3693 m2, R. pseudoacacia – 2,9478 m3 and 0,8350 m2, P. rallasiana – 3,1626 m3 and 0,3279 m2.


HortScience ◽  
1992 ◽  
Vol 27 (11) ◽  
pp. 1169c-1169
Author(s):  
Curt R. Rom ◽  
Renae E. Moran

Trunk cross-sectional area (TCA) has been used to estimate leaf area (LA) and yield efficiency but variation in LA and TCA relationships have been unexplored. LA and TCA of 10-yr-old 'Starkspur Supreme Delicious' on 9 rootstocks (STKs) were measured in 1989. LA and TCA of 2-yr-old trees of 3 cultivars (CVs) on 5 STKs were measured in 1991. Regression of LA and TCA was performed for each CV, STK and each CV/STK. On mature trees, LA varied significantly with STK. The number and LA of shoot leaves (LVS) and spur LVS varied with STK but the % of total was not significantly different (approx. 52% spur LVS). The relationships of LA and TCA were linear for mature (r2=.94) and young (r2=.44) trees. On young trees, TCA varied with CV, but LA did not. Both LA and TCA were significantly different among STKs. The linear relationships of LA and TCA had unique intercepts with each CV, STK and CV/STK combination but slopes were not significantly different. Leaf area of Jonagold' and 'Gala' tended to increase more with increasing TCA than 'Empire'.


Author(s):  
V. M. Zverkovsky ◽  
O. S. Zubkova

The linear growth of forest plantations of Western Donbass’ recultivating plot №1 were studied. The established cross-sectional the area of trunks and timber reserves experimental trees.Characterized by parameters which are the volume of wood: its height, diameter at breast height and shape of the forming barrel. In diameter at breast height cross sectional area is determined and then the barrel volume is calculated. Cross sections of tree trunks are shaped like a circle or an ellipse. Knowing the volume of logs we calculated reserves of wood for trees experimental plots.The largest reserves of timber and cross-sectional area characterized planting U. pumila – 15,367 m3 and 1,9583 m2, A. platanoides – 13,328 m3 and 2,67 m2, Q. robur – 10,120 m3 and 1,452 m2, J. virginiana – 8,748 m3 and 2,106 m2. The least plantation stocks of wood characterized E. angustifolia – 1,3699 m3 and 0,3693 m2, R. pseudoacacia – 2,9478 m3 and 0,8350 m2, P. rallasiana – 3,1626 m3 and 0,3279 m2.


HortScience ◽  
2017 ◽  
Vol 52 (9) ◽  
pp. 1233-1240 ◽  
Author(s):  
James R. Schupp ◽  
H. Edwin Winzeler ◽  
Thomas M. Kon ◽  
Richard P. Marini ◽  
Tara A. Baugher ◽  
...  

Pruning is the cutting away of vegetation from plants for horticultural purposes. Pruning is known to reduce apple tree size, increase fruit size and quality, and decrease yield. Methods for studying the effects of varying degrees of severity of pruning on a whole-tree basis have used qualitative descriptions of treatments rather than repeatable whole-tree quantitative metrics. In this study, we introduce a pruning severity index calculated from the sum of the cross-sectional area of all branches on a tree at 2.5 cm from their union to the central leader divided by the cross-sectional area of its central leader at 30 cm from the graft union. This limb to trunk ratio (LTR) was then modified by successively removing the largest branches of ‘Buckeye Gala’ to achieve six severity levels ranging from LTR 0.5 to LTR 1.75, with lower values representing more extreme pruning with less whole-tree limb area relative to trunk area. Pruning treatments were applied for three consecutive years and tree growth and cropping responses were observed for the first 2 years. With increasing pruning severity the following characteristics increased after seasonal growth: number of renewal limbs, number of shoots, shoot length, number of shoot leaves, shoot leaf area, final fruit set, fruit size, yield of large fruit, crop value from large fruit, soluble solids, and titratable acidity. The following characteristics decreased: limb age, number of secondary limbs, number of spurs, number of spur leaves, spur leaf area, the ratio of spur leaf area to shoot leaf area, fruit count per tree, yield, yield efficiency, crop value from small fruit, overall crop value, and sugar:acid ratio. The LTR provides a measurable way to define and create different levels of pruning severity and achieve consistent outcomes. This allows a greater degree of accuracy and precision to dormant pruning of tall spindle apple trees. The use of the LTR to establish the level of pruning severity allows the orchard manager to set crop load potential through regulation of the canopy bearing surface. This metric is also a necessary step in the development of autonomous pruning systems.


HortScience ◽  
2005 ◽  
Vol 40 (4) ◽  
pp. 1038C-1038
Author(s):  
Timothy L. Righetti ◽  
Carmo Vasconcelos ◽  
David R. Sandrock ◽  
Samuel Ortega ◽  
Yerko Moreno

Four ratio-based efficiency expressions (yield/trunk cross-sectional area, yield/canopy area, yield/pruning weight, CO2 assimilation/leaf area) were evaluated. These expressions depend on the size of the denominator if the function describing the relationship between the denominator and the numerator has a non-zero intercept. When this occurs, it is difficult to determine if statistically different efficiency expressions reflect physiological differences or are caused by comparing expressions with different sized denominators. When denominators and numerators of efficiency expressions are plotted, the edge of the data cloud can often be statistically identified. The function describing the edge of the data cloud defines the maximum possible value (MPV) obtainable for a given value of the denominator. The percentage of MPV (%MPV) is an alternate efficiency expression that is not influenced by differing trunk cross-sectional area, canopy area, pruning weight, or leaf area. The difference between MPV and observed performance can be used to define improvement potential (IP). These alternate assessments can supplement traditional efficiency expressions. It is also possible to determine if statistical differences in traditional efficiency expressions are caused by differences in potential, differences in a plant or leaf's ability to achieve its potential, or differences in the size of the efficiency expression denominators.


2005 ◽  
Vol 35 (5) ◽  
pp. 1250-1255 ◽  
Author(s):  
Petru Tudor Stancioiu ◽  
Kevin L O'Hara

Coast redwood (Sequoia sempervirens (D. Don) Endl.) trees in different canopy strata and crown positions were sampled to develop relationships between sapwood cross-sectional area and projected leaf area. Sampling occurred during the summers of 2000 and 2001 and covered tree heights ranging from 7.7 to 45.2 m and diameters at breast height ranging from 9.4 to 92.7 cm. Foliage morphology varied greatly and was stratified into five types based on needle type (sun or shade) and twig color. A strong linear relationship existed between projected leaf area and sapwood area at breast height or sapwood at the base of the live crown despite the variability in foliage morphology. Ratios of leaf area to sapwood were 0.40 m2/cm2 at breast height and 0.57 m2/cm2 at crown base. Measurements of sapwood at the base of the live crown improved leaf area predictions because of sapwood taper below the crown base. A sapwood taper model was also developed.


1975 ◽  
Vol 5 (3) ◽  
pp. 503-505 ◽  
Author(s):  
J. Harry G. Smith

Measurements of cross-sectional area outside bark at breast height in a spruce – subalpine fir forest were studied to determine the effects of plot size on minimum and maximum amounts of basal area sampled per unit area. Assuming a good relationship between basal area and biomass of trees, the need for careful interpretation of stand weight estimates on small plots is illustrated.


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