CRAFT program

Newly Planted Trees and HLB

Ernie NeffHLB Management, Root health

Newly planted

Newly planted trees need to have root systems that are as established, robust and healthy as possible before contracting HLB, Evan Johnson told growers at Citrus Expo. That’s because HLB takes out a tree’s fibrous root system and causes dieback of the structural root system. Having strong root systems from the start will increase the productive life of trees, the University of Florida Institute of Food and Agricultural Sciences citrus root pathologist said.

“As the roots start to die back, you will lose productivity of that tree,” Johnson said.

He offered several suggestions for ensuring young tree root health, starting with testing grove soil before planting and picking rootstocks that match the soil. Ordering trees from a reputable nursery is also important. Johnson suggested growers avoid rootbound root systems by not having nurseries hold the trees too long. When trees are delivered, make sure they are not rootbound and are healthy, he said.

Break up the young tree’s rootball to induce root growth and to allow it to take up water, Johnson advised. “People get in a rush,” and some planters tend to skip this step, he warned.

Another planting tip Johnson offered: Don’t jam trees into the hole when planting. “That’s another thing that happens normally when planters get in a big hurry; they start really jamming them down and that can cause j-rooting,” leading to problems similar to having a rootbound tree, he said.

Monitor and treat for phytophthora as needed, “especially if you have a history of phytophthora in a site,” Johnson recommended. “At this point, we’re not sure if it’s economically viable to treat phytophthora once HLB moves into a grove,” he said.

Johnson has been focusing for several years on the impact of HLB on tree root health and ways to keep root systems healthy in the face of HLB.

Hear more from Johnson:

Share this Post

About the Author

Ernie Neff

Senior Correspondent at Large