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?

Share

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

Sunday - July 27, 2008

From: Littleton, CO
Region: Rocky Mountain
Topic: Pruning, Shrubs
Title: Eradication of mahonia repens
Answered by: Barbara Medford

QUESTION:

What is the best way to kill and/or remove mahonia repens?

ANSWER:

Mahonia repens (creeping barberry) is native to Colorado, and is a stoloniferous, sprawling evergreen. It is widely praised as a low groundcover with fruit attractive to birds, and listed as a non-invasive alternative to several invasive plants. However, "invasive" is in the eye of the beholder, and we can see how having it in the wrong place in your garden could be a problem. The fact that it is stoloniferous means that it spreads like some grasses, with below-ground root systems spreading it very efficiently.

To begin, and to get a better feel for the situation, start pruning away and discarding the cuttings in such a way that no berries left on the cuttings will get a chance to propagate themselves. You're clearing the area so you can find where the plant comes up from the root. When you find that, cut it through as near to the ground as you can. Paint the newly-cut surface with an appropriate herbicide, at nearly full strength, with a disposable sponge paintbrush, within 5 minutes. The herbicide must go on the cut area quickly before it begins to "heal" itself, thus preventing the herbicide from getting down to the roots. Now, because it is stoloniferous, you still have to deal with those roots. That plant is going to be trying to survive, no matter what you do, so the more damage you can do to the roots, the better. Drive a sharp shovel into the ground and cut them, expose them and prune them, or whatever method works best for you. Grubbing out the stump and discarding it will also effectively starve any remaining roots. You will have to continue to be alert; the plant propagates by roots sending out new little plants and by seeds that may have fallen months before. Just keep pulling them out until the shrub is exhausted. The best time to do this is in the Summer, when the heat and the sun will help in your destruction.

We didn't say it was going to be easy.

 

More Pruning Questions

Hedge of native Purple Sage in Austin
November 20, 2008 - Hi, I would like to plant a dense hedge of Purple Sage that will hopefully grow from 6-8 ' tall and about 4' wide. I purchased the Silverado Sage Leucophyllum frutescens 'Berstar Dwarf' variety....
view the full question and answer

Replacing non-native boxwood in Austin
October 03, 2011 - I have a large maze garden, possibly boxwood, originally planted in the 1950's, in Austin, Texas. About 1/3 of it has died out, probably due to drought, heat and age. Should I attempt to replant ju...
view the full question and answer

Trimming dead blooms from turkscap in San Antonio
July 10, 2009 - Great answer to the Turk's Plant question. But, I can't seem to find an answer to mine. I've had Turk's plants for years and cut them back as you suggest, but have always been confused about wha...
view the full question and answer

Why aren't my Forsythias blooming in Stone Mountain, GA?
March 24, 2010 - We have a large forsythia stand that has bloomed beautifully for 14 years in a row. Two summers ago I cut them way back in July. For the past two years they have only leafed out, no, or very few bloom...
view the full question and answer

Late winter pruning of native Texas Sage
January 27, 2005 - I have several Texas Sage bushes that have started to get very woody and have growth only on the top. This seems to have led to a definite listing to one side. Should I trim these to the ground or...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP | STAFF
© 2016 Lady Bird Johnson Wildflower Center