Native Plants

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?

Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants

See a list of all Smarty Plants questions

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

rate this answer

Not Yet Rated

Tuesday - October 26, 2010

From: Alexander City, AL
Region: Southeast
Topic: Trees
Title: Wax myrtles dying in Alexander City AL
Answered by: Barbara Medford

QUESTION:

I have a difficult problem with my wax myrtle plants dying. I have 36 Wax Myrtle bushes, approximately 10 feet high and they are dying, one at a time. They look fine and then within a week the leaves turn brown and in two weeks the bush is dead. I have been observing the wax myrtle plants as more are dying. The leaves start to die at the branch tips and work their way down the branch. If I cut a branch off it stops the progression. I also note that if one bush dies the adjacent bush toward the dead plant starts to die. Plant history: The 36 wax myrtle plants were planted in the year 2003. They came from the Southern Gardens nursery in pots and were about three feet high. They are now about ten feet high. In 2007 plants #2 through #7 died, one at a time from #2 through #7 in that order. Plants #1 & #36 were in distress but lived. In 2008 plants #2 through #7 were replaced. In 2010 plants #7 & #35 have died & plants #1, #9, #34 and #36 are in distress. The plants appear to be well rooted and grew well until they starting dying. I thought the problem may have been insects but could not see anything under a 10X lens. I did spray a few plants near the dead ones. I appreciate any help you may provide. Thank you.

ANSWER:

We would first like to refer you to a Mr. Smarty Plants previous question. This also dealt with slow die-off of Morella cerifera (Wax myrtle). The plants in that question were more recently planted, but the similarities in the fact that not only did plants near each other die in succession, but no insect vector was apparent. We have been recommending wax myrtles because they are evergreen and attract many kinds of birds. However, we are beginning to think they may not be as strong and problem-resistant as we would like.

First, we wanted to be sure that this particular plant should have been planted where you live. This USDA Plant Profile shows them growing natively in about the lower 1/2 of Alabama. It would appear that they do not grow in Tallapoosa County; however, these maps get out of date, and there is no reason they could not grow there. But the fact that they grow only in one portion of the state, basically, would lead us to believe that there is a problem with the soil, particularly since you replaced some of your wax myrtles with new ones, which also died.

Extracted from another previous answer:

"Morella cerifera (wax myrtle) is generally resistant to disease and insect problems, though stem canker and a leaf fungus can sometimes attack individual plants. Your plants may have been affected by a stem canker disease. Prune the dead wood back until you find living tissue." In our research, we found no references to this plant being susceptible to things like cotton root rot, and it is apparently unknown if it is susceptible to verticillium wilt. So, we're back to looking at the growing conditions you have on your property, and how well they fit the plant. From the page on this plant in our Native Plant Database, here is the information on the ideal environment for wax myrtle.

Growing Conditions

Water Use: High
Light Requirement: Sun , Part Shade
Soil Moisture: Wet , Moist
Soil pH: Acidic (pH<6.8) , Circumneutral (pH 6.8-7.2)
CaCO3 Tolerance: Medium
Drought Tolerance: Medium
Heat Tolerant: yes
Soil Description: Slightly acidic, moist, deep sands, loams, clays.
Conditions Comments: Requires constant moisture to get established, but both drought- and flood-tolerant once established. If temperature goes below zero degrees F, will defoliate, not releafing until spring. Tolerant of saline conditions and urban confinement within pavement.

We would think you would have acidic soil where you are, but perhaps not. Also according to our database:
"Native Habitat: Moist forest; marshes; fresh to slightly brackish stream banks; swamps"

Since we are obviously are at a loss attempting to answer your question, we suggest you contact the Alabama Cooperative Extension Office for Tallapoosa County. They could even get a soil analysis for you, in case the soil acidity is incorrect for your plants.

From our Native Plant Image Gallery:

Morella cerifera