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Thursday - April 07, 2011

From: Mt. Pleasant, TX
Region: Southwest
Topic: Grasses or Grass-like
Title: Removing Purple Top Tridens out of Mt Pleasant Texas
Answered by: Leslie Uppinghouse

QUESTION:

We would like to know how to kill these Purple Top Triden out of our garden. Thanks, Judy

ANSWER:

We are guessing that you are looking to remove Tridens flavus (Purpletop tridens) out of a formal garden situation, because this grassy gem is highly coveted by Texans and a great native grass to add to the landscape. We will first talk about all the plusses with this grass in case you have a change of heart.

Purpletop tridens are lovely visually in mass from late summer through the fall. It is light, moves with the wind and has a deep pink color at the top. A great grass for a shady location as it is as happy in the shade as it is in the sun. Tridens hold the ground in place even in sandy soil and can take harsh soil conditions as in clay loam. A good grass for a leach field or areas that are hard to keep pretty. It does not require much water and if you look over the growing conditions in the link, you will see that it is listed as preferring dry soil. 

Livestock will consume it, so if you need it mowed, borrow your neighbors goat. A great hiding grass for nesting birds and also a favorite of many butterflies. A key larval host to skippers and wood nymphs.

Back to your original query. Tridens are not easy to get rid of. It holds the ground in place well, due to its fibrous and rhizomatous root system. Remove the grass now before the late summer seeding. As it is a perennial grass, the seed from last year has already set and the new grass should be showing. Now is the time to dig it up. 

You need to dig it out carefully. Be thorough enough to collect all of the roots and not leave behind the rhizomes. The goat idea isn't really as much of a joke as it sounds. One of the advantages of having a goat handle the first round of trimming is that the animal will consume any seed left on the grass. This would be a better option than mowing it down with a mower and then digging it out. If you don't have a goat handy, then dig it out tall but be careful not to shake out any seed still left on the plant from last season.

After you have dug everything out, if you feel confident that you have been thorough, till the dirt up then comb through the dirt again with your hands and pull out any small roots that have been left behind. Do not skip the digging step and head straight for the tiller. If you do, you risk chopping up the rhizomes and spreading the grass, rather than removing it.

Anytime you have to do any real digging, work smart, not hard. Wait for a good rain or water the area the night before you take on the project. You need the soil loose enough for you to remove all of the plant material without breakage. Having the soil moistened will make your life a lot easier enabling you to complete the task faster. Before you toss the Tridens out for good, look around your property for an area that has been hard to plant or a slope that could use some stability, it really is a very nice grass.

 

 

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