Bastard cabbage under fire from state

AUSTIN (KXAN) - Texas Department of Transportation crews are preparing to mount a counterattack against bastard cabbage , an invasive weed that is threatening to crowd out and overrun wildflowers all over the state, including our beloved bluebonnets .

“We're going to be looking at using some herbicides in the fall of the year, when this plant germinates that are selective to the mustard, but not to species like legumes," said TxDOT vegetation manager Dennis Markwardt.

“And, of course, the bluebonnet, being a legume, hopefully we can use these applications to control that bastard cabbage, while leaving some of the bluebonnets.”

The weed, originally from North Africa and Central Europe, is part of the mustard family. In fact, leaves from bastard cabbage are actually eaten by people in those regions, usually boiled or fried, but sometimes raw in salads.

That, however, is little consolation to worried Texans as they look out over wide swaths of the yellow-blooming weed growing rampant along state highways and covering nearby pastures.

At the Lady Bird Johnson Wildflower Center , invasive species expert Dr. Damon Waitt is worried.

“If we don't do something about this,” he said, “we're going to have to say goodbye to our Texas wildflowers, including the bluebonnet.”

“We kind of joke around a little bit about the bastard cabbage because of its funny name,” Waitt said, “but, you know, honestly, I think the phrase we're using: ‘Hello, bastard cabbage, goodbye bluebonnets,’ has a ring of truth to it.”

At TxDOT, Markwardt agrees, especially if the 2011 drought takes an encore this summer.

“We lost tremendous amounts of grass last year due to the drought,” he said. “We had all kinds of open soil and bare ground. The bastard cabbage really took advantage of all these bare areas and it really grew well. It was a great year for it.”

Markwardt acknowledges that TxDOT crews also disturb sections of highway right-of-way during construction projects. Those areas, he said, are quickly reseeded with grasses which are certified weed-free. Still, vehicles hauling agricultural products like hay can spread contamination up and down the roadways.

“Highways have always been a vector for moving plants around,” he said.

Both Markwardt and Waitt say they have been deluged with calls about the bastard cabbage invasion, especially in the wake of a report on the subject last week, by KXAN News .

According to the TxDOT vegetation manager, many callers want to know why crews are not mowing the weed.

The answer, he says, is that mowers will take out the favored wildflowers along with the cabbage and raising the mowers to pass over the shorter bluebonnets creates problems of its own.

“When you start mowing high,” said Markwardt, “you start having issues like the bastard cabbage will resprout and put on its flowers again.

“Also when you mow high, you've got a safety issue: If you hit anything, a bucket, a sign, a piece of wood, you're going to get a mower-thrown object and that's going to pose a safety problem to the traveling public.”

But crews do spot-mow when the tall yellow-flowering plants block roadway sight-lines.

So the main assault on the bastard cabbage will not come until herbicide treatments are unleashed later in the year after next season’s crop begins to grow. If, as Markwardt hopes, the poisons hit the mustard-type cabbage hard and spare the legume-type bluebonnets, the bully-like weed should take a beating next spring.

“Now, the trade off is,” he said, “some of our other good wildflowers aren't legumes, like our Indian blankets and paint brush and these types of species.”

There is also another problem with spraying: Ingredients and techniques are still being developed.

“Some of these things may work well and some of them may not,” said Markwardt. “That's some of the research that we've got ongoing right now.”

Even in the best case scenario, though, the bastard cabbage appears to be here to stay.

“Our best goal for what we can do,” Markwardt said, “is learn how to live with it and manage it so it's not causing us the problems that we see today. I don't think we'll ever eradicate it.”

Perhaps the best chance for beating back the cabbage, though, will come not from an herbicide tank, but from the sky in the form of rain for the grass.

“If we get good grass recovery,” Markwardt said, “it probably won't be as bad next year; if we don't get good grass recovery from a good wet summer, we're going to be in the same place next year.”

Meanwhile, many callers to the department and to the wildflower center have been volunteering to head out onto the rights-of-way to manually wrestle the bastard cabbage plants, deep tap-root and all, out of the ground. It’s not an easy task and Markwardt doubts many people would stay with the job for long.

Still, the TxDOT, he says, always appreciates the public’s help. There is a proper way to proceed, however.

“The right-of-way is a dangerous place,” said Markwardt, “and so if people are going to do this,