En Español

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

Wednesday - May 13, 2009

From: Victoria, TX
Region: Southwest
Topic: Non-Natives, Pruning, Trees
Title: Problem with crapemyrtle shoots in Victoria, TX
Answered by: Barbara Medford


I have a problem with crepe myrtle shoots coming up in my flowerbed. I had to remove a large crepe myrtle tree (18" diameter stump) and digging out the stump was not possible. I killed the stump with diesel poured into holes drilled into the base; however shoots keep coming up from the root system which is extensive. I have tried weed killer which kills the shoots, but new ones replace them almost immediately. What can I do? Help.


Now you know one of the reasons the Lady Bird Johnson Wildflower Center recommends only plants native not only to North America but to the area in which they are being grown. Lagerstroemia indica, (crapemyrtle) is native to temperate and tropical Asia, including, among others, China, Bangladesh, and Nepal. We have heard many complaints about the messiness of the plant, the sap dripping onto cars and people (usually because the tree is infested with aphids), and, of course, its invasiveness, which is what you are experiencing. We frankly had never tried pouring diesel into a stump to kill it, glad you survived the experience, and it appears the roots survived, too. Here is what we suggest for getting rid of a plant that won't go away voluntarily. We don't like to recommend herbicides, but this is an extreme case. Get a small bottle of glyphosate systemic herbicide, which is sold under several brand names. Get some disposable paintbrushes. Now, try to trim some more off the stump, all the way across, and paint that new area, right away, with the herbicide. You need to do it quickly, because within 5 minutes the tree (which obviously still has live roots) will be healing itself over to prevent the entry of that herbicide into the root system. Each time a new shoot comes up, either cut it and paint it with more of the herbicide, or try to dig it out down to the root. The root has a lot of nutrients stored up in it and is one of the survival tactics of plants, but the roots also need leaves to get the sunshine for photosynthesis and manufacture more food. It will take some time and patience but eventually the roots will starve and give up and die. You may also be experiencing some seedlings coming up; remember those ugly seed pods all over the tree? Pull those out while they are still small enough to get roots and all.

And, above all-be careful with that herbicide! Don't let it get on the ground if you can help it, and don't spray. You don't want to contaminate the soil where you will probably wish to plant something else (if the diesel hasn't already done so), and you sure don't want spray drift to damage some plants you already have. 


More Non-Natives Questions

Non-native upside down tomatoes in Edmonton AB
September 19, 2010 - Due to early frost, I have brought my upside down tomato plant into the house & have hung it in the basement. What type of grow lamp can I use? I just have the overhead light & standard lamps at my di...
view the full question and answer

Mowing wildflower concerns from Lockhart TX
March 30, 2012 - I went to the Texas Highway Department (Texas Department of Transportation) web site and sent them a concern or complaint about them or independent contractors shredding the roadsides before the blueb...
view the full question and answer

Non-native mimosa failing to bloom in Leitchfield KY
October 29, 2011 - I have a medium size mimosa tree here in KY that usually blooms beautifully; it did not bloom at all this year. It leafed out well, needs a few dead limbs pruned, but seems otherwise healthy. Please t...
view the full question and answer

Native plants of Rome
February 22, 2009 - I am researching the native plants of Rome but I can't get anything get anything else besides olives. Can you help me to find some more?
view the full question and answer

Smarty Plants on fungal attack
October 12, 2005 - I have three plants that have been getting fungus on their soil and I've tried to get rid of it by scraping it off, watering it less and more sunlight. It's two coleus and a begonia. I don't know...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2016 Lady Bird Johnson Wildflower Center