New technology to improve post-plant survival and stress resistance in urban trees

2006 | Bruce R. Roberts, Ohio Wesleyan University

The successful establishment of trees after transplanting (post-plant) is a major challenge facing all segments of the arboricultural industry.  While many factors influence post-plant success, substantial root loss at harvest combined with the limited ability of damaged situation root systems to absorb adequate moisture for ‘normal’ physiological activity are major reasons why transplant shock frequently results in the death of newly transplanted trees and shrubs.  This is only exacerbated for trees planted at urban sites, many of which exhibit characteristically poor growing conditions.  The use of traditional amendments incorporated into the backfill soil around newly planted trees has been suggested as a means for stimulating post-plant growth, nutrient efficiency and stress resistance.  Composted waste products, humate-based root stimulants, hydrophilic gels and various mycorrhizal-containing substrates are among the many additives that have been tested, all with very limited success.

Recently, a new generation of organic humectant compounds has been developed that offer the potential for improving water balance in the rhizosphere immediately surrounding the root system of newly transplanted trees and shrubs.  These non-conventional soil additives, which attract free water molecules from air spaces within the soil matrix, are environmentally safe and remain active in the soil for extended periods of time.  Despite its potential for ameliorating transplant shock, this new methodology has not been investigated in the arboricultural industry.

This study examined the efficacy of using new humectant technology to improve post-plant survival and performance of containerized woody seedlings. The study examined post-plant root growth, shoot development, whole-canopy photosynthesis and plant-water relationships of drought-stressed woody seedlings grown in media amended with a commercially available liquid organic humectant.

Year: 2006

Funding Duration: 3-5 years

Grant Program: Hyland Johns

Grant Title: New Technology to Improve Post-plant Survival and Stress Resistance in Urban Trees

Researcher: Bruce Roberts

Key words: Transplanting; root conditions; transplant shock; humectants; water availability

Peer Reviewed Publications from Grant:

  • Roberts, BR and RS Linder. 2010. Humectants as post-plant soil amendments: Effects on the wilting cycle of drought stressed, container-grown tree seedlings.  Arboriculture & Urban Forestry 36:275-280. View the Publication >
  • Roberts, BR, RS Linder, CR Krause and R Harmanis. 2012. Humectants as post-plant soil amendments: Effects on growth and physiological activity of drought-stressed, container-grown tree seedlings.  Arboriculture & Urban Forestry 38:6-12. View the Publication >

General Audience/Trade Publications: none

Presentations: none

For more information on this project, contact the researcher via TREE Fund at