Industry Insights With Florida Grower John Conroy
John interviews Dr. Ed Gilman: urban tree specialist, prolific author and University of Florida environmental horticulture professor.
He teaches the architecture of tree branch and root structure, and why it is critical for tree success in the landscape.
John: You’ve taught us that roots deflected during their stay in the nursery can compromise the longevity of that tree. Trees can even become unstable when roots are deflected. What are some things landscapers can do to ensure a healthy root system?
Ed: You want a healthy rootball, and you should inspect the roots at delivery. Get in there and get dirty and take a closer look. The important defects are near to the top of the rootball close to the trunk, meaning that observations can be quick. If the tree was initially grown in a small container and the roots are all in a knot, it will be very loose in the soil versus if the roots go straight out. High quality trees have straight roots at or near the top of the rootball. These trees become stable and establish quickly. Having to stake a tree that’s 3-4 inches in diameter because its unstable can be a sign of poor quality. People are spending hundreds and even thousands of dollars on a single tree, and if it goes south because of bad roots, that’s a big problem. The tree can look green and have a high vitality but be unstable. We’ve seen this in hurricanes. Healthy, vigorous trees of any caliper down by the thousands.
John: You can shave the outside of a container root system to make sure from that point forward you have a radiating root system, but what might have happened previously is difficult to correct. The roots could have developed improperly from the get-go, even in the original propagation container. Often by the time the tree gets to a one-gallon container, it’s too late.
Ed: Yes, I think if we can make small changes in the first few weeks and months after propagation, we can increase the quality of our plant material and reduce the likelihood of failure. We need to teach more people how to inspect roots, prune at planting and use a grades and standards document which details the proper development and care for trees. This practice will help move the industry forward.
In the July/August issue, John will discuss more about Florida Grades and Standards for Nursery Plants and its impact for the betterment of the industry.