Research results on container size and tree establishment

A debate has long raged over the benefits of planting larger versus smaller size container nursery stock. Dr. Michael Arnold (Texas A&M University) sought to resolve this dilemma scientifically in the study, “Long- Term Impact of Container Size on Tree Establishment.” To minimize variation in nursery production factors, he used clonal materials and produced all of the tree sizes in a common nursery using similar materials. He was also able to track tree response over seven years – two in the nursery and five in the field – generating solid long-term data.

Dr. Arnold’s painstaking work revealed that as long as 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.

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 tradeoffs between immediate aesthetic impacts and longer term tree performance.

Read the detailed findings on this project and discover additional TREE Fund studies related to soil, planting, and establishment on the Research Archive page of the TREE Fund website.

Arnold’s research can be read at