scholarly journals Production Method and Irrigation Affect Root Morphology of Live Oak

1997 ◽  
Vol 15 (2) ◽  
pp. 84-87
Author(s):  
Michael D. Marshall ◽  
Edward F. Gilman

Abstract Trees of live oak (Quercus virginiana Mill.) were container-grown (CG) or field-grown (FG) to a mean trunk diameter of 9.4 cm (3.7 in), transplanted into sandy soil, and established with frequent or periodic irrigation. Three years after transplanting, trees were harvested with a 1.5 m (60 in) diameter tree spade. Root number and root cross-sectional area was evaluated for all roots at the periphery of the tree-spade-dug root ball. Despite similar increases in trunk diameter, FG trees had greater root number and root cross-sectional area than CG trees. The greater root cross-sectional area occurred in roots 5–20 mm (0.2–0.8 in) in diameter at soil depths of 0–25 cm (0–9.8 in) and 75–100 cm (29.5–39.3 in). Irrigation frequency after transplanting had no effect on root number in FG trees. However, root number in CG trees was lower without frequent irrigation.

HortScience ◽  
1996 ◽  
Vol 31 (4) ◽  
pp. 605f-606
Author(s):  
Michael D. Marshall ◽  
Edward F. Gilman

Quercus virginiana trees were container-grown (CG) or field-grown (FG) to a mean trunk diameter of 9.4 cm (3.7 inches), transplanted into sandy soil, and established with frequent or periodic irrigation. Three years after transplanting, trees were harvested with a 1.5-m- (60-inch-) diameter tree spade. Root number and root cross-sectional area was evaluated at the periphery of the tree spade-dug root ball. Despite similar increases in trunk diameter, FG trees had greater root number and root cross-sectional area than CG trees. The increase in root cross-sectional area occurred for roots 5 to 20 mm in diameter at the 0- to 25-cm and 75- to 100-cm soil depths. Irrigation frequency after transplanting had no effect on root number in FG trees; however, root number in CG trees decreased without frequent irrigation.


2006 ◽  
Vol 24 (2) ◽  
pp. 74-76
Author(s):  
Yin-Tung Wang ◽  
Genhua Niu

Abstract Rhizomic shoot cuttings of live oak (Quercus virginiana Mill.) were taken from a single tree about 50 years old in late August 1990, rooted, and planted into 2.6 liter (#1) plastic pots. Concurrently, acorns were collected from the same tree and germinated. Trees from both sources were planted into 13 liter (#5) plastic pots in July 1991 and then to the field in July 1992 either directly in the ground, in 37 or 46 cm (14 and 18 in) diameter polypropylene fabric bags buried in the ground, or in 13 liter pots (#5) placed on the surface. Trunk circumference 10 cm (4 in) above the soil line was measured yearly between 1993 and 1999. Initially, trees from rhizomic shoot cuttings grew slower than seedlings based on trunk circumference, diameter, and cross-sectional area. However, there were no statistical differences after 1996 in trunk circumference, diameter and cross-sectional area between the trees propagated from rhizomic shoot cuttings and seeds. Only in 1993, trees in 37 cm (14 in) bags and plastic pots had greater growth than trees in the ground. About one-third of the seedling trees produced rhizomic shoots in comparison to none of the trees from rhizomic shoot cuttings.


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. Ivonin ◽  

Purpose: to investigate the flow-regulating role of forest belts in connection with their taxation characteristics. Methods: artificial sprinkling of soils under the forest belts canopy. Results. Pseudoacacia robinia prevails in the forest belts in Rostov region (basin of the Kundryuchya river, ordinary chernozems). By the age of 35, this species can reach an average height of 12 m, an average diameter of 12 cm. Regression equations for the relationship of the runoff coefficients with the average height of Robinia pseudoacacia and its average diameter, wood reserves of forest belts and cross-sectional areas of trunks were obtained. These taxation characteristics determine the precipitation absorption intensity through the tree waste bulk and forest flor, root saturation, water-physical and chemical properties of the topsoil, which change with the age of plantings. When the age of 20 years is exceeded, the forest belts will completely absorb high intensity rainfall. At this age, the Robinia pseudoacacia will exceed the average height of 9.4 m, and its average trunk diameter will approach 10 cm. At the same time, the stock of raw wood in the forest belt will reach 57 m³/ha, and the cross-sectional area of the trunks – 11 m²/ha. The functional relationship between soil erosion and runoff coefficients confirms the close relationship between soil erosion and the main taxation characteristics of forest belts. The analysis of these relationships showed that storm erosion of soil under the forest canopy is completely absent when the taxation indicators reach the following values: the average Robinia height is 9 m, the average trunk diameter is 9.2 cm, the stock of wood is 46 m³/ha, the cross-sectional area of the trunks is 10.2 m²/ha. Conclusions. By the age of the forest belts 20 years, the runoff under the forest canopy will be completely regulated, and there will be no soil erosion. Forest belts older 20 years need to enhance their flow-regulating capacity by combining them along the lower edge with the simplest hydraulic structures.


2010 ◽  
Vol 36 (4) ◽  
pp. 183-190
Author(s):  
Edward Gilman ◽  
Chris Harchick ◽  
Maria Paz

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.


2016 ◽  
Vol 42 (3) ◽  
Author(s):  
Edward Gilman ◽  
Maria Paz ◽  
Chris Harchick

Root pruning by shaving 12 L container root balls when shifting to 51 L containers did not impact Acer rubrum L. or Quercus virginiana Mill. root architecture within the top 12 cm of planted 51 L root balls five years later, despite marked differences at planting, and had no impact on tree height or trunk diameter increase. Root pruning in the nursery did not affect bending stress required to tilt Acer trunks up to five degrees (anchorage) either one, two, or three years after landscape planting. In contrast, anchorage was greater the second year after planting Quercus that were root pruned. Rotating trees 180 degrees at planting from their orientation in the nursery had no impact on Acer or Quercus anchorage, tree height, or trunk diameter. Rotating oak (not maple) trees 180 degrees at planting increased root cross-sectional area growing from the hot (south) side of the root ball when trees were rotated at planting.


2020 ◽  
Author(s):  
Hannah M. Schneider ◽  
Jennifer T. Yang ◽  
Kathleen M. Brown ◽  
Jonathan P. Lynch

AbstractUnder nitrogen limitation, plants increase resource allocation to root growth relative to shoot growth. The utility of various root architectural and anatomical phenotypes for nitrogen acquisition are not well understood. Nodal root number and root cross-sectional area were evaluated in maize in field and greenhouse environments. Nodal root number and root cross-sectional area were inversely correlated under both high and low nitrogen conditions. Attenuated emergence of root nodes, as opposed to differences in the number of axial roots per node, was associated with substantially reduced root number. Greater root cross-sectional area was associated with a greater stele area and number of cortical cell files. Genotypes that produced few, thick nodal roots rather than many, thin nodal roots had deeper rooting and better shoot growth in low nitrogen environments. Fewer nodal roots offset the respiratory and nitrogen costs of thicker diameter roots, since total nodal root respiration and nitrogen content was similar for genotypes with many, thin and few, thick nodal roots. We propose that few, thick nodal roots may enable greater capture of deep soil nitrogen and improve plant performance under nitrogen stress. The interaction between an architectural and anatomical trait may be an important strategy for nitrogen acquisition. Understanding trait interactions among different root nodes has important implications in for improving crop nutrient uptake and stress tolerance.


2009 ◽  
Vol 35 (6) ◽  
pp. 281-286
Author(s):  
Edward Gilman ◽  
Jason Grabosky

One codominant stem on each of 48 similar Quercus virginiana Highrise® trees was pruned to evaluate impact of pruning severity on growth suppression and partitioning. Targeted pruning severity (0, 25, 50 or 75% foliage and subtending branches removed) based on visual estimates of two people correlated well (r2 = 0.87) with the ratio stem cross-sectional area removed: crosssectional area at base of the pruned codominant stem. Pruning reduced cross-sectional area growth on codominant stems compared to the leader stem that was not pruned, especially during the first 12 months following pruning. Increased pruning severity reduced cross-sectional area growth on the pruned stem in proportion to amount of foliage removed. In each of three years following pruning, cross-sectional area of the unpruned leader stem increased more on trees receiving targeted pruning severities of 25% or 50% than trees pruned with the 75% severity or trees not pruned. Shift in growth from the pruned to unpruned portion of the tree reduced diameter ratio between the two stems, which should make the union stronger. Diameter ratio changed most for the 75% pruning severity.


1994 ◽  
Vol 07 (03) ◽  
pp. 110-113 ◽  
Author(s):  
D. L. Holmberg ◽  
M. B. Hurtig ◽  
H. R. Sukhiani

SummaryDuring a triple pelvic osteotomy, rotation of the free acetabular segment causes the pubic remnant on the acetabulum to rotate into the pelvic canal. The resulting narrowing may cause complications by impingement on the organs within the pelvic canal. Triple pelvic osteotomies were performed on ten cadaver pelves with pubic remnants equal to 0, 25, and 50% of the hemi-pubic length and angles of acetabular rotation of 20, 30, and 40 degrees. All combinations of pubic remnant lengths and angles of acetabular rotation caused a significant reduction in pelvic canal-width and cross-sectional area, when compared to the inact pelvis. Zero, 25, and 50% pubic remnants result in 15, 35, and 50% reductions in pelvic canal width respectively. Overrotation of the acetabulum should be avoided and the pubic remnant on the acetabular segment should be minimized to reduce postoperative complications due to pelvic canal narrowing.When performing triple pelvic osteotomies, the length of the pubic remnant on the acetabular segment and the angle of acetabular rotation both significantly narrow the pelvic canal. To reduce post-operative complications, due to narrowing of the pelvic canal, overrotation of the acetabulum should be avoided and the length of the pubic remnant should be minimized.


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