En EspaŅol

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
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.
 
rate this answer
Not Yet Rated

Thursday - March 15, 2012

From: Austin, TX
Region: Southwest
Topic: Invasive Plants, Meadow Gardens, Grasses or Grass-like
Title: Should the herbicide Ornamec 170 be used on unwanted grasses?
Answered by: Guy Thompson

QUESTION:

I have a lovely wildflower garden in a field behind my house; unfortunately, the wildflowers are being smothered by grasses. I understand that Ornamec 170 can be used to control grasses in wildflower gardens. Do you recommend it and, if so, do you know of a local source here in Austin?

ANSWER:

For various reasons I urge you not to use the herbicide Ornamec 170.

1. This herbicide, a formulation of the chemical fluazifop-P butyl, is very toxic.  Extensive precautions must be made in order to avoid getting the compound on your skin or breathing its vapors.

2.  Ornavic 170 is not readily biodegradable, and no food crop can be grown on land where it was used for a full year.  It should not be used on land near a stream or ditch because runoff following a rain would bring the herbicide into contact with sensitive animals, including humans.  (I presume that the field behind your house belongs to you.  If not, you  would have to get permission from the owner before using this herbicide.)

3.  Ornavic 170 has not been evaluated for a wide variety of plants.  It may not kill all the grass species that you  have, and it may kill some of the wildflowers you wish to preserve.

4.  I suspect that some undesirable broad-leaf plants are also smothering the wildflowers in your field. These would not be killed by Ornavic 170.

Your best bet would be to bite the bullet and pull the worst of the weeds from the site yourself by hand, hopefully with the help of friends or hired neighborhood kids.

If you choose to disregard my sound advice, Ornamec 170 and a similar herbicide, Grass-B-Gon, are available from Amazon.com.  I have also seen Grass-B-Gon in some of the big box stores and in nurseries in Austin.  Skip Richter, former Travis County horticulturist, suggests using a sponge soaked in the herbicide to brush against the undesirable plants rather than spraying all the plants, good and bad.  But it would take little more effort to just pull up the individual plant or hoe it down instead.

 

More Meadow Gardens Questions

How to make a lawn into a prairie in Arlington, Texas
September 15, 2010 - I am removing lawn grasses in order to start a native prairie meadow. After grass removal, I'll put down 1/2" of compost. I will broadcast wildflower seeds on the compost. If I mulch after broadcas...
view the full question and answer

Grasses for a prairie in southeast Texas
September 30, 2013 - We have a small place (about 100 acres) in Colorado County, Texas, on the Colorado River north of the town of Weimar. We are gradually clearing (bulldozing) the woods of cedars. One particular spot ...
view the full question and answer

Restoring a prairie from Austin
January 11, 2013 - Restoring a mixed grass Blackland Prairie? Prairie Plant Succession? We are trying to establish climax species when an area is in a pioneering phase. Does the soil chemistry or biota change during ...
view the full question and answer

Ground cover for a bank in PA
April 28, 2012 - I live in Landisburg, PA, (zone 6). I need to find some ground cover for a primarily full sun bank that is roughly 10-12' down over the embankment and up to 100' long. This area wraps around our po...
view the full question and answer

Revegetation of school site with meadow plants from Austin
December 23, 2013 - We are revegetating a hill country school site (typical calciferous soil stripped of vegetation & minimal topsoil) with a native seed mix equal to Native American Seed "Meadow Mix". We have an abund...
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP | STAFF
© 2015 Lady Bird Johnson Wildflower Center