Long-Term Impact of Container Size on Tree Establishment

2015 | Dr. Michael Arnold, Texas A&M University

Initial efforts from this research project provided substantial quantified evidence to support the old adage that smaller transplanted stock would catch up with larger transplanted stock, but that differences in the time required to achieve equivalent landscape sizes varied among species. Some limits also existed relative to extremely small stock from #1 containers for slower growing tree species. Trees from as small as #3 containers for some rapid growers, such as chastetrees, had caught up in landscape size to #25 and #45 containers after only three growing seasons. Others such as Drummond red maple and baldcypress were exhibiting similar trends but had not yet converged on a similar size. The work funded here will permit these studies to be carried on to encompass a full five growing seasons in the field to quantify in more detail the time required to establish trees ranging from #1 to #45 containers. This represents 2 years of production in the nursery plus 5 years of data in the field, an opportunity seldom available in a controlled research setting made possible by industry support of TREE Fund. This research should prove very useful for urban foresters, commercial landscapers and consumers in making informed choices about the rate of transplanted tree establishment, costs associated with different container size stock, and the trade-offs between immediate aesthetic impacts and longer term tree performance.

Study Results

Vitex agnus-castus (Chaste tree), Acer rubrum var. drummondii (Drummond maple), and Taxodium distichum (Bald cypress) were propagated clonally in a sequential manner over two growing seasons and transplanted to consecutively larger containers to obtain #1, #3, #7, #25, or #45 sizes and then transplanted to a sandy clay loam field. After two growing seasons in the field trees from the four larger containers of V. agnus-castus did not differ in height, with only trees from #1 containers lagging behind. By the third year no differences in height were found among trees from all five container sizes of V. agnus-castus. Acer rubrum did not differ in height among container sizes by the end of the fourth growing season. For slower growing T. distichum trees, no differences existed among the heights of the three largest container sizes by the end of the fifth growing season and those from the two smaller size containers lagged only slightly behind. Patterns of responses were similar for trunk diameter and canopy spread. Rapid root elongation into the soil surrounding the planted root balls during the first two seasons after transplant correlated with rapid shoot growth. Substantial economic benefits accrued in as little as two growing seasons after transplanting using smaller #3 or # 7 stock in comparison to larger stock. If one is willing to forego the immediate aesthetic impacts, ecosystem services, and greater ability to withstand mechanical damage of larger-size container stock, similar longer-term sizes in the landscape can be achieved by transplanting less expensive, more easily handed, smaller container-size trees.

     

Year: 2015

Funding Duration: 1-3 years

Grant Program: John Z. Duling

Grant Title: Long-Term Impact of Container Size on Tree Establishment

Researcher: Mike Arnold

Key words:

Peer Reviewed Publications from Grant:

General Audience/Trade Publications:

Presentations:

  • Arnold, M.A. 2018. Enhancing landscape sustainability through efficient establishment and selection of regionally adapted plants. Texas A&M University Research and Extension Center at Dallas, Dallas, TX, 18 May 2018.
  • Arnold, M.A., L.M. Garcia Chance, L. Lombardini, W.T. Watson, S.T. Carver, and A.R. King.  2017. Do little dogs catch the big dogs after a while – or does container size matter? SERA 27 2017 Annual Meeting, Nursery & Landscape Symposium : Pretty Tough Plants – New Evaluations and Selections from Across the South, Tennessee State University Nursery Research Center, McMinnville, TN.  June 2, 2017.
  • Garcia, L.M., M.A. Arnold, L. Lombardini, W.T. Watson, S.T. Carver, and A.R. King.  2016.  Patience is a Rewarded Virtue with Small Container-Grown Trees.  2016 International Society of Arboriculture Annual International Conference and Trade Show, Fort Worth, TX, Aug. 13-17. Abstract: http://eventmobi.com/api/events/12097/documents/download/b32e4d59-97e4-4c4f-aa6d-bdefc3b35a4e.pdf/as/ISA%20extended%20abstract%20-%20Arnold%202016.pdf.

 

For more information on this project, contact the researcher via TREE Fund at treefund@treefund.org.