Native Plants
![](../_images/smarty_plants.gif)
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.
Did you know you can access the Native Plant Information Network with your web-enabled smartphone?
Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.
![](../_images/mr_smarty_plants_logo_web_200w.jpg)
rate this answer
![](../_images/star_31.gif)
Friday - October 19, 2012
From: Austin, TX
Region: Southwest
Topic: Invasive Plants, Non-Natives, Problem Plants, Shrubs
Title: A method for killing nandina and ligustrum with herbicide
Answered by: Guy Thompson
QUESTION:
Is there an effective herbicide that can be painted on the stumps of Nandina and Wax-leaf ligustrum to keep them from growing back? Thanks so much!ANSWER:
One widely-used method is to either cut down the plant near ground level or girdle the trunk with an axe or chainsaw so that the cambium layer is exposed. The cambium layer is the ring of cells just beneath the bark. It's functions include transporting nutrients made in the leaves by photosynthesis down into the stem and roots and transporting water from the roots up to the leaves. Some woody plants can be killed simply by cutting through the cambium, but other species, including Nandina and Ligustrum, can sprout new growth from the stump. To prevent this the cut cambium layer should be painted with CONCENTRATED Roundup herbicide (not the diluted form sold to spray on leafy vegetation). The herbicide should be applied within a very few minutes after disrupting the cambium. Otherwise it will not be taken up by the plant effectively.
Roundup concentrate can be obtained from some garden centers or hardware stores. Roundup persists in nature for only a few days, but it is toxic to some animals while it lasts. That is why you must carefully paint it on with a small brush rather than spraying over a larger area. And do not use it withing a few feet of a stream or pond because rain could carry it into the water, where it would kill aquatic organisms.
Although this kind of herbicide treatment will usually kill the main plant stem, certain invasive plants, such as Tree of heaven, are capable of sending up new shoots from roots some distance away from the killed parent plant. That is not likely to happen with Nandina or Wax-leaf ligustrum. However, it is wise to monitor the situation for some months to assure that new suckers are not appearing in the vicinity.
More Invasive Plants Questions
List of North American plants grown in other countries
August 17, 2008 - I am working on a childrens story and would like to let the teachers who read this book know where some of the native plants in my book grow throughout the world, or if they grow outside of the USA. p...
view the full question and answer
Wild mustard growing in disturbed ground in Montana
August 01, 2008 - I have recently planted "plugs" of wildflowers in beds throughout my yard. Because the soil was disturbed, I now not only have some beautiful wildflowers growing, but also mustard plants growing in ...
view the full question and answer
Removal of invasive roots of Turks Cap in College Station TX
April 29, 2014 - I know people have asked you questions about propagating Turk's Cap, but my question is a little different. I have this plant growing in several locations, because I have a large garden with lots...
view the full question and answer
Lists of edible plants in region of Pennsylvania for school project
September 12, 2006 - Please Help! I'm a grade four teacher in Philadelphia. My students and
I are assigned a theme project that involves listing edible plants that
grow in our region. Can you recommend a web site(s)...
view the full question and answer
Japanese honeysuckle invading a backyard habitat in Austin
April 29, 2010 - It has been a few weeks since we have been to our backyard (it is a place in need of desperate attention, but we have been re-landscaping the front yard first). When we went out today to start plannin...
view the full question and answer
Support the Wildflower Center by Donating Online or Becoming a Member today. |