Limp Locust Leaves - Ask Extension
My wife and
I need your advice regarding a Locust tree we planted in our south-facing front
yard last year. It replaced an Ash that had succumbed to V...
Knowledgebase
Limp Locust Leaves #183159
Asked May 19, 2014, 2:05 PM EDT
My wife and
I need your advice regarding a Locust tree we planted in our south-facing front
yard last year. It replaced an Ash that had succumbed to Verticillium Wilt.
Bill Cassel, who is an Arboreal Inspector for Denver, suggested a possible replacement
choice would be some variety of Honey Locust. He made a point of suggesting it
be a container grown tree. We thought we had purchased one, but when we removed
it from the pot there was hardly any root. Last summer it developed
Thyronectria canker, which can happen to a new tree with poor roots, according
to your fact sheet.
Here is our dilemma: from what you can see from the attached photos, are the limp leaves being caused by Verticillium Wilt, Thyronectria canker, or something else? I checked the moisture content of the soil and it was very moist. If it is being caused by Verticillium Wilt, I am thinking the soil will not support any type of tree. If the wilting is a result of the effects of last year’s canker, then we will buy another Locust and make sure this one is container grown. Have you any suggestions of where we might find a ‘container grown’ tree and how we can even tell?
We would appreciate your thoughts.
Sincerely, Steve and Margaret Beatty
Here is our dilemma: from what you can see from the attached photos, are the limp leaves being caused by Verticillium Wilt, Thyronectria canker, or something else? I checked the moisture content of the soil and it was very moist. If it is being caused by Verticillium Wilt, I am thinking the soil will not support any type of tree. If the wilting is a result of the effects of last year’s canker, then we will buy another Locust and make sure this one is container grown. Have you any suggestions of where we might find a ‘container grown’ tree and how we can even tell?
We would appreciate your thoughts.
Sincerely, Steve and Margaret Beatty
Denver County Colorado
Expert Response
Verticillium wilt affects primarily catalpa, ash, elm, maple and sumac. Honeylocust is resistant, so that is not the cause of your honeylocust's limp leaves.
It is far more likely that the Thyronectria canker (a fungal disease of stressed honeylocust and some other trees) is the cause - the tree leafed out on stored energy while it was cooler. Now that it has gotten warmer, there is more transpiration (water loss) through leaves. A limited root system and water "blockage" because of the dead tissue under the canker means that more water is lost through leaves than is being replaced.
This is not to suggest that you flood the planting area daily. But it might help to mulch (wood chips, straw, pine needles or similar material) a 6-8 foot wide area around the trunk, about 2-2.5 inches deep. Don't let mulch stack up against trunk, instead pull it away from trunk several inches. Mulch will keep the soil cooler and moist.
If you do lose this honeylocust, try another in the same spot.
Garden centers/nurseries may have container-grown honeylocusts that are container-grown.
It is far more likely that the Thyronectria canker (a fungal disease of stressed honeylocust and some other trees) is the cause - the tree leafed out on stored energy while it was cooler. Now that it has gotten warmer, there is more transpiration (water loss) through leaves. A limited root system and water "blockage" because of the dead tissue under the canker means that more water is lost through leaves than is being replaced.
This is not to suggest that you flood the planting area daily. But it might help to mulch (wood chips, straw, pine needles or similar material) a 6-8 foot wide area around the trunk, about 2-2.5 inches deep. Don't let mulch stack up against trunk, instead pull it away from trunk several inches. Mulch will keep the soil cooler and moist.
If you do lose this honeylocust, try another in the same spot.
Garden centers/nurseries may have container-grown honeylocusts that are container-grown.
Dear Robert Cox,
Thank you for your response. Just one last question: Will a container grown tree say so on the container's label, or do we need to rely on the salesperson? Once again, we appreciate your help.
Steve and Margaret Beatty
Thank you for your response. Just one last question: Will a container grown tree say so on the container's label, or do we need to rely on the salesperson? Once again, we appreciate your help.
Steve and Margaret Beatty
Probably not; ask salesperson. Many honeylocusts would be "balled-in-burlap" and then placed in a larger plastic container. You could ask if they would lift rootball out of larger container to see if rootball is wrapped in burlap.
Smaller honeylocusts, say in a #5 pot, are likely to have been grown in that container.
Smaller honeylocusts, say in a #5 pot, are likely to have been grown in that container.
