scholarly journals Pruning Severity and Crown Position Influence Aspect Ratio Change

2015 ◽  
Vol 41 (2) ◽  
Author(s):  
Edward Gilman
Keyword(s):  
Aspect Ratio ◽  
Trunk Diameter ◽  
Crown Position ◽  
Live Oak ◽  
Ratio Change ◽  
Over Time

Growth on one branch is suppressed in proportion to pruning severity, resulting in a predictable reduction in branch:trunk diameter (aspect) ratio. However, little is known about response to pruning multiple branches. Several of the largest branches on live oak (15.3 cm trunk diameter) were pruned with four severities (0%, 25%, 50%, and 75%), then branch, nearby stem, and trunk diameter were measured for five subsequent years. Rate of trunk diameter increase five years after pruning was greatest for trees pruned with the 25% severity. Aspect ratio on all three pruned and measured branches decreased with time after pruning, pruning severity, and increasing height in the crown. Mean aspect ratio ceased declining between three and five years after pruning. The decrease in aspect ratio over time and with increasing severity on pruned branches was less pronounced in the lower crown than in the upper crown. Smaller change in aspect ratio on pruned branches in the lower crown suggests that when structurally pruning trees, branches in the lower crown may require a higher pruning severity to effect the same change in aspect ratio as upper branches.

scholarly journals Lowering of Calcareous Soil pH in Field-Grow Containers

1990 ◽  
Vol 8 (1) ◽  
pp. 1-4
Author(s):  
G. Kidder ◽  
M.J. Holsinger ◽  
T.H. Yeager
Keyword(s):  
Calcium Carbonate ◽  
Soil Ph ◽  
Calcareous Soil ◽  
Fine Sand ◽  
Iron Sulfate ◽  
Trunk Diameter ◽  
Application Rates ◽  
Live Oak ◽  
Ph Reduction ◽  
One Year

Abstract Wettable sulfur (S) mixed with a Pineda fine sand (an Arenic Glossaqualf with 7.8 pH and 1.5% calcium carbonate equivalent) quickly acidified the soil, but the effect was lost within 8 weeks at low application rates and within 21 weeks at the highest rate (1 g S/kg soil or 1 lb S/1000 lb soil). Granular S mixed with the soil took one year to produce maximum pH reduction of 0.3, 0.4, and 0.9 pH units at 250, 500, and 1000 mg S/kg soil (1/4, 1/2, and 1 lb S/1000 lb soil), respectively . Wettable sulfur (S), surface-applied at 100 g/m2 (0.036 oz/10 ft2), lowered the pH of the upper 5 cm (2 in) of soil to the 5.6 to 5.8 range for one to two months before the pH returned to > 7.0; granular S took about five months to lower the pH to 6.7 but the soil pH was 6.2 two years after application. Wettable S at 20 g/kg soil (0.32 oz S/lb soil) in a small cylindrical zone resulted in a temporary depression of pH within the treated zone but had no effect on pH in other areas of the container. Mixing up to 1.0 g iron sulfate/kg soil (0.016 oz/lb soil) failed to reduce soil pH. Live-oak trunk diameter and plant height were not affected by any of the soil treatments in the two-year experiment.

scholarly journals Irrigation and Fertilizer Placement Affect Root and Canopy Growth of Trees Produced in In-ground Fabric Containers

1995 ◽  
Vol 13 (3) ◽  
pp. 133-136
Author(s):  
R.C. Beeson ◽  
E.F. Gilman
Keyword(s):  
Shoot Growth ◽  
Fine Root ◽  
Production Cycle ◽  
Root Mass ◽  
Field Site ◽  
Fertilizer Placement ◽  
Trunk Diameter ◽  
Quercus Virginiana ◽  
Live Oak ◽  
Chinese Elm

Abstract Live oak (Quercus virginiana Mill.) and Chinese elm (Ulmus parvifolia Jacq. ‘Drake’) were transplanted from 3.8 liter (#1) containers into 35-cm (14 in) fabric containers in sandy soils. Irrigation or fertilizer was applied all inside, half-in half-out (50/50), or all outside the fabric container during a 2-year production cycle. For live oak, neither irrigation nor fertilizer placement increased fine root mass within the fabric container. Maximum trunk diameter was achieved by applying both irrigation and fertilizer inside the container. For Chinese elm, applying either fertilizer or irrigation inside or half-in half-outside the container increased fine root mass within the harvested root ball. Elm shoot growth was greatest with 50/50 placement of both irrigation and fertilizer. Field site influenced the effect of Irrigation on shoot growth, but not root mass. Greater fine root mass occurred in the heavier soil type

scholarly journals Impact of Paclobutrazol on Root-pruned Live Oak

2011 ◽  
Vol 21 (1) ◽  
pp. 46-50 ◽  
Author(s):  
Tomás Martínez-Trinidad ◽  
W. Todd Watson ◽  
Russell K. Book
Keyword(s):  
Chlorophyll Fluorescence ◽  
Tree Growth ◽  
Starch Content ◽  
Root Pruning ◽  
Glucose Content ◽  
Trunk Diameter ◽  
Quercus Virginiana ◽  
Live Oak ◽  
Full Rate ◽  
The Impact

This study evaluated the impact of paclobutrazol (PBZ) on the overall growth and vitality of root-pruned, field-grown live oak (Quercus virginiana). Live oak trees with 10-cm trunk diameter (measured 30 cm aboveground) were treated with full rate (0.8 g·cm−1 trunk diameter) of PBZ as basal drenches, full or half rate (0.8 or 0.4 g·cm−1 trunk diameter) of PBZ and trenching at 45 cm from trunk, full or half rate of PBZ and trenching at 60 cm from trunk, trenching alone at 45 or 60 cm from trunk, and only water. Trunk diameter and canopy growth was significantly reduced (P < 0.001) and new root growth was also reduced by applications of PBZ, root pruning, or both. Starch content in twigs decreased and glucose content increased on treatment by full-label rates of PBZ and root pruning at 60 cm. PBZ and/or root pruning caused slight improvements in chlorophyll fluorescence (Fv/Fm). Results of this research indicate that PBZ (full rate) in combination with root pruning (45 cm) reduces tree growth and exhibits an overregulation effect for at least 16 months after treatment. Therefore, PBZ applications on root-pruned trees can temporarily decrease root and tree growth and improve foliage chlorophyll fluorescence.

Elements in leaves of a trembling aspen clone by crown position and season

1976 ◽  
Vol 6 (3) ◽  
pp. 436-440 ◽  
Author(s):  
Elon S. Verry ◽  
D. R. Timmons
Keyword(s):  
Growing Season ◽  
Trembling Aspen ◽  
Sampling Schemes ◽  
Minor Elements ◽  
Crown Position ◽  
Upper Third ◽  
Over Time

Concentrations of N, Ca, K, P, Mg, Na, Zn, Mn, Fe, Al, B, and Cu were determined in the leaves of a 43-year-old stand of Populustremuloides Michx. by upper, middle, and lower crown positions and for seven sampling dates over the growing season. Concentrations of Ca and K in the upper third crown position were consistently lower than those in either the middle or lower third positions by an average of 0.19 and 0.20% ovendry weight, respectively. Concentrations of Mg and Na remained constant over time; concentrations of N, K, and P continually decreased over time; and minor elements showed a net increase over the growing season with an intermediate peak on June 30. Suggestions for sampling schemes are given.

scholarly journals Response of Two Oak Species to Reduction Pruning Cuts

2007 ◽  
Vol 33 (5) ◽  
pp. 360-366
Author(s):  
Jason Grabosky ◽  
Edward Gilman
Keyword(s):  
Aspect Ratio ◽  
Surface Area ◽  
National Standards ◽  
Quercus Virginiana ◽  
Branch Angle ◽  
Live Oak ◽  
Lateral Branches ◽  
Quercus Shumardii ◽  
Cut Surface

Reduction pruning cuts were used to prune Quercus virginiana (live oak) and Quercus Shumardii (shumard oak). One-half of the pruning wounds were harvested and dissected 3 years later to observe extent of discoloration in response to the pruning cut. Shumard oak did not limit discoloration as effectively as live oak. Discolored area in the wood increased with size of the pruning cut surface in shumard oak and less so in live oak. Dissections showed that the shape of the discolored area attenuated with depth. The branch connection morphology and response (branch–trunk aspect ratio, branch angle, release growth after pruning) appeared to influence discoloration pattern in reduction pruning. The angle of the reduction cut relative to the American National Standards Institute-recommended angle bisect method was not found to influence discoloration. Discoloration in the less efficient compartmentalizing species (Shumard oak) was related to cut surface area, but not to cut angle. There was no relationship between aspect ratio and discoloration in the 3 years after pruning. The data suggest that reduction cuts can be made back to lateral branches as small as one-third the diameter of the removed stem.

scholarly journals Examination of Infrared Tomato Drying

2020 ◽  
Vol 4 (1) ◽  
pp. 303-309
Author(s):  
Zsombor Várkonyi ◽  
Viktória Sebesi ◽  
Mária Örvös
Keyword(s):  
Heat Source ◽  
Process Optimization ◽  
Radiation Power ◽  
Market Demand ◽  
Drying Process ◽  
Moisture Variation ◽  
Ratio Change ◽  
Insight Into ◽  
Over Time ◽  
Sample Distance

Tomato is a highly perishable food, thus preservation is required to meet the continuous market demand compared to the unbalanced yearly production peak. The aim of this paper is to show a detailed insight into infraradiation based drying process. Furthermore, to widen the possible usage range of a well-known approximation method for describing the temporal moisture variation in function of process parameters. The mass decrease of tomato slices was examined, in function of specific radiation power, heat source and sample distance, in forced and natural airflow. Based on the results dimensionless moisture ratio change over time was fitted as an exponential function, which may be used in industrial drying process optimization.

scholarly journals Effect of Tree Size, Root Pruning, and Production Method on Establishment of Quercus virginiana

2010 ◽  
Vol 36 (4) ◽  
pp. 183-190
Author(s):  
Edward Gilman ◽  
Chris Harchick ◽  
Maria Paz
Keyword(s):  
Potential Field ◽  
Production Method ◽  
Root Pruning ◽  
Field Soil ◽  
Xylem Water Potential ◽  
Trunk Diameter ◽  
Quercus Virginiana ◽  
Live Oak ◽  
Field Nursery ◽  
Establishment Rate

Significant differences may exist in establishment rate between trees planted from containers and those from field nursery. Containergrown plants have root balls with deflected roots which could impact establishment. Slicing root balls at planting could improve postplanting performance of container-grown trees. Sixty live oak 170 L containers were planted into landscape field soil. Root balls from 30 of these containers were sliced prior to planting. Thirty field-grown trees of slightly larger size, and 30 smaller trees from 57 L containers, were also planted. During dry periods in the first 432 days after planting (DAP), 57 L container trees had the least negative xylem potential. Field-grown trees had the most negative xylem potential when irrigation was withheld 12 DAP. Slicing root balls had little impact on xylem water potential in drought. Defoliation was greater for 170 L container trees than for 57 L containers. Trunk diameter increase of 57 L containers and field-grown trees was greater than for 170 L containers. Field-grown trees grew less in height. Root system radius was similar for 170 L containers and field-grown trees, and greater than 57 L containers. Small trees appear to establish quicker than larger trees.

scholarly journals Temporal and Spatial Glucose and Starch Partitioning in Live Oak

2009 ◽  
Vol 35 (2) ◽  
pp. 63-67
Author(s):  
Tomas Martinez-Trinidad ◽  
W. Todd Watson ◽  
Michael Arnold ◽  
Leonardo Lombardini
Keyword(s):  
Old Field ◽  
Tissue Samples ◽  
Developmental Patterns ◽  
Tree Vitality ◽  
Trunk Diameter ◽  
Glucose Levels ◽  
Quercus Virginiana ◽  
Live Oak ◽  
Time Of Year ◽  
Source Sink

Carbohydrate translocation, which follows anatomical and developmental patterns, is ruled by source-sink relations where energycontaining compounds are moved from sources of production to sinks of utilization. Seasonal carbohydrate concentrations in various tree parts were measured and compared in 10 cm (4 in) trunk diameter live oaks (Quercus virginiana P. Miller). Tissue samples from roots, trunks, twigs and leaves were collected from three-year-old field-grown trees on four dates throughout the 2005–2006 seasons. Laboratory analyses of glucose and starch were performed, and values were compared and contrasted according to sample location and time of year. Glucose levels were significantly higher in leaves during the winter (P ≤ 0.001), while starch concentrations were significantly higher in root and trunk tissues during the spring and winter assessments (P ≤ 0.001). Carbohydrate concentrations varied among tissues sampled within the tree. This study provides valuable information on the spatial and temporal partitioning of energy reserves, glucose and starch, in live oak so that arborists will have a better understanding of tree vitality, and the effects and environmental impacts of arboricultural treatments.

scholarly journals Analysis of Aspect Ratio Effects on Transonic Rotor Performance Using a 3D Viscous Solver

1998 ◽  
Author(s):  
Cecil R. Buchanan ◽  
Paul R. Emmerson ◽  
Michael Spruce
Keyword(s):  
Aspect Ratio ◽  
Numerical Study ◽  
Navier Stokes ◽  
Test Cases ◽  
Compressor Rotor ◽  
Aspect Ratios ◽  
Radial Profiles ◽  
Ratio Change ◽  
The One ◽  
Good Agreement

This paper presents the results of a numerical study into the effects of aspect ratio on compressor rotor performance. The test cases studied are NASA rotors 37 and 38, which have aspect ratios of 1.19 and 1.63 respectively. A 3D, single-passage steady flow Navier-Stokes solver was used to predict complete performance characteristics, including the numerical instability point, for both rotors. The predictions are generally in good agreement with the test data (characteristics, radial profiles and rotor over tip measurements) at all conditions modelled for rotor 37. The performance for rotor 38 is overpredicted, with slightly less than half of the measured performance difference between the two rotors being captured. The effect of a pure aspect ratio change (divorced from the rotor inlet to exit area changes present in the rotor 37/38 comparisons) was also investigated, and a case with an aspect ratio double that of rotor 37 was also modelled. The results indicated that the code predicted little effect on rotor performance due to an aspect ratio change alone (from 1.19 to 2.38). This is surprising and it raises doubts about the ability of current codes (or at least the one used in the study) to predict this important aspect of a compressor design adequately.

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