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

Abstract

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.

Assessment of Six Indicators of Street Tree Establishment in Melbourne, Australia

“…A number of factors can influence successful street tree establishment, including inappropriate selection of stock, low-quality stock, poor planting technique, insufficient irrigation, lax weed control, and inadequate maintenance (Watson 1987;Ward et al 2000;Gilman et al 2010;Kenney et al 2011). The effectiveness of street tree planting may be determined by whether the individual trees have established and by their long-term performance (Bühler et al 2007).…”

“…Some researchers have used the term to indicate that newly planted trees have shown canopy growth, which may be measured as height increment (Sinnett al. 2008) or a combination of caliper, height, and crown spread (Day et al 2009;Gilman et al 2010). Others have included measures of root spread and root growth (Sinnett et al 2008;Gil-man et al 2010), and some have simply recorded whether trees have survived (Day et al 2009), or have measured tree vitality using shoot growth and the health of canopy tissues (Bühler et al 2007).…”

“…The first few years immediately after transplant are critical to establishment and it is during this time that factors influencing establishment have the most profound effect (Watson 1992). There are opportunities for improved street tree management by evaluating establishment and predicting potential success (Struve 1993;Day et al 2009;Gilman et al 2010). Urban tree managers also need reliable, accurate and practical indicators of whether street trees have successfully established to inform decisions about removal of supporting stakes, whether irrigation regimes should be continued for recently planted trees, and whether poorperforming trees should be removed and replaced.…”

“…Tree establishment and the level of performance are different components of street tree growth. Tree establishment relates to the extension of the root system of the recently planted tree into the backfill soil that stabilizes it in the ground and increases the volume of resources available to the tree (Sinnett et al 2008;Gilman et al 2010). Establishment also requires that the canopy has adequate health, structure, and growth to allow the subsequent successful growth of the street tree in the long term (Day et al 2009;Gilman et al 2010).…”

“…Tree establishment relates to the extension of the root system of the recently planted tree into the backfill soil that stabilizes it in the ground and increases the volume of resources available to the tree (Sinnett et al 2008;Gilman et al 2010). Establishment also requires that the canopy has adequate health, structure, and growth to allow the subsequent successful growth of the street tree in the long term (Day et al 2009;Gilman et al 2010). Tree performance is assessed by how the tree grows within the landscape over time and is often characterized by measures such as growth rate, height increment, canopy spread and density, and measurements of girth increase.…”