No, this isn’t one of my one-act inter-active murder mystery comedies. This is about Guinea grass, Urochloa maxima.
Left to its own devices, whether we’ve had a three-year drought or great rainfall, Guinea grass (and Berumda grass, Cynondon dactylon, whose roots I swear go to China) are listed in reference books with strong negative comments such as
· “the worst field and lawn weeds in the Lower Rio Grande Valley” where they are
· “undesirable, aggressive weedy species” that
· “deplete soil moisture” and
· “exclude nearly all of the native herbaceous species.”
So, what do you do if one of your gardens falls victim to the above scenario?
There are options:
· shoot it with Round-up
· level with a weed-trimmer string device or machete
· mow it down
· shoot it some more
· dig out Guinea grass clumps, roots and all, with a garden fork or shovel
· dig out root clumps after weed-trimming and killing with Round-up
· or all of the above
Sad to say, but sometimes you just have to kill everything and start over.
Incredibly, some of the plants that were actually planted where you wanted them may still survive. The blades of Guinea grass are wide and long, the clumps so thick and over-towering, you might still find a sleeper underneath. Quite possibly, the Round-up spray won’t even touch the planned plants hiding beneath it.
Once Guinea grass clumps are dead, unfortunately, they must be dug out of the ground. I don’t recommend putting the roots in a compost pile. I don’t think anyone recommends anything but putting the roots in a yard bag for trash collection — Guinea grass roots are hard to kill.
Some people stash dug-up roots in black plastic lawn bags left to “cure” in the hot Texas sun for some time, and then consider it safe to re-use the refuse. That practice is sensible in out of the way places, for instance like in Hugh Ramsey Nature Park, but may not be practical in your home landscaping.
Ideally, you want to get the Guinea grass project going prior to it going to seed.
Before you wage war, have a plan to revegetate. You can experiment and let vegetation come back on its own and pluck out errant growth while it’s still young. This works of course, if you have time to give the required vigilance to keep your native garden in check.
Even if you plant newly purchased plants in your newly cleared space, frequent checks for new-growth Guinea grass is wise.
Guinea grass isn’t the only culprit that can send a garden into a tangled mess.
A number of our native plants, when left untended for one reason or another, can get out of hand.
Shrubs get too tall or spread out and block other plants; mistflower can get unwieldy; plumbago can overpower neighboring plants; Turk’s cap can get leggy stretching for the sun; and ruella, scarlet sage, snapdragon vine and cowpen daisy can re-seed themselves silly. Undetected vines can gain a stranglehold. Coreopsis and dicliptera can devour the earth.
Frank Wiseman, Rio Grande Valley Chapter, Texas Master Naturalist plant guru, recently had help leveling one of his side gardens. His friend wielded a machete until nothing was left but one-inch stems. Thank you, Frank for sharing the following photos.
Frank rescued his delicate Yellow Sophora shrub, Sophora tomentosa, from out-of-control Turk’s cap, mistflower and non-native ruellia.
In nature parks and in nature itself, dominant and aggressive vegetation takes a strong-hold, choking out other species. That’s where volunteers are invaluable to our nature preserves — providing a labor force to maintain nature walks and uncover diverse species. See Anita’s Blog (March 2016) Rescuing Rarities.
In Hugh Ramsey Nature Park, along with Guinea grass, the dicliptera, granjeno and mesquite trees are continually being dealt with to highlight other species, or to start over and design a new specialty garden.
The preferred method of destruction — whether it be Round-up, weed trimmer, machete, loppers, flame-thrower — is your choice.
Check out our Website’s list of RGV native plant nurseries: http://rgvctmn.org/rgv-plants/
Compare Ruellia nudiflora var. runyonii (left photo below) to non-native Ruellia (right photo below).
Anita,
I really like the article. Sensible approach to ridding the garden of dreaded guinea grass and replanting with other native south Texas plants. Excellent.
Thank you, Frank. Labor-intensive, that’s for sure. But as we both know, a small sprig of Guinea grass one day becomes a two-foot monster as soon as you turn your back.
It has been my experience on Guinea grass that you need to kill the roots or it will come back. Digging up the roots disturbs the ground and other nodes may be set up to come back.
My recommendation is use roundup or other grass specific herbicide to kill the roots. These herbicides are biodegradable and will dissipate in a few days.
I have also noticed that when you kill the Guinea grass roots and the ground becomes bare (without disturbing it), native plants will grow on that spot.
Thanks,
Jimmy
You make some very good points, Jimmy, especially about the nodes. That makes sense.
When you say, without disturbing it, do you mean you do not dig the dead roots out? – Thanks – Anita