Another bad invasive: Malta star-thistle

Malta star-thistle (Centaurea melitensis)
Similar species is yellow starthistle (Centaurea solstitialis)

Here recently, I must admit that I felt a little relieved to know that we don't have the bastard cabbage (Rapistrum rugosum) in our neighborhood. Then last Wednesday, I met Ricky Linex, a wildlife biologist with the Natural Resources Conservation Service, at a Riparian Workshop (part of my Texas Master Naturalist training). On a creek bank near Horseshoe Bay, he pulled up a dark green plant and said it was the invasive thistle he mentioned to me earlier.

Malta star-thistle (Centaurea melitensis). It's just as bad as bastard cabbage.


Hmmm.


In the meantime, James and I had been eyeing a healthy crop of big green plants growing along the street that adjoins the Meadow. Uh oh.


After I got home, I took a closer look at the plants.


Dang.


We've got Malta star-thistle IN OUR WILDSCAPE!!

Yesterday evening, James started pulling it up. I pulled up more around noon today and walked across the street, too, to yank up some growing in our neighbor's yard. We've got a LOT more to pull. And there's more young ones coming up.


Drat.


Sigh.


Just now, I reported our thistle to Early Detection & Distribution Mapping System, a web-based mapping system for documenting invasive species distribution. My Record ID for the Malta star-thistle is 2027636. 


LATER THAT EVENING...

Here we go after supper, back to work on the Malta star-thistle. Bad stuff! Last year, the city scraped this side of the street for sewage work, and then left it be. We should have tried to reseed it, I guess. At any rate, this thistle showed up in full force.

It took everything I had to pull up some of the thistle!!! I think it should have a similar name as that bastard cabbage....

Daunting work, but we kept at it.

I asked James to take a photo of what's UNDER a cluster of thistle. NOTHING.

James won the prize for the biggest thistle of the evening.

We removed the majority of the Malta star-thistle...for now. We'll have to keep pulling until hopefully we win and not the thistle. 

* * * *

More info on invasives:


National Invasive Species Information Center

Invasive Species, AgriLife Extension, Prairie View A&M University




UPDATE APRIL 2, 2012


I asked Ricky some questions about best how to control the species:

"There are chemical methods, but the plants might still produce seed because of the length of time required for the chemical to work. Hoeing or pulling will get roots and all. According to a forest service pub mowing and I suppose weed-eating can cause the plant to send out side branches. Google "Field Guide for Managing Malta Star-thistle" to read more."


Can the piled up bunches of pulled thistle still make seeds?


"If it hasn't produced yellow flowers, it won't now make seed. The ones you've pulled were caught early so they are done. And forgot to add that the untouched plants will bloom different heads through early summer."

UPDATE, MAY 12, 2012

I am still pulling Malta star-thistle and beggar's ticks (Torillis arvensis), another non-native. The species is also called hedge parsley. You've seen the stuff...it has pretty white flowers that resemble baby's breath or Queen Anne's lace. Then the flowers turn into nasty burrs that stick to socks and fur. As I was yanking the plants, I noticed that the species--like most invasive weeds--crowds out everything and creates a monoculture (nothing grows under it)!

My pile of thistle and beggar's ticks.

More caterpillar deaths and some new (alive) ones

More melting caterpillars, this one on a dead lantana stem.

I spotted another dead one on a different stem.

This small unidentified caterpillar was alive.

I'm only posting this damselfly because while I was shooting it....

...I happened to see ANOTHER dead caterpillar on a blade of grass!

Found on our wooden arbor...another Grote's buck moth (Hemileuca grotei), according to Bugguide.net. "Once again based on the red coloration between segments," Ryan wrote. "Hemileuca peigleri is the only other Hemileuca sp. I would expect from Blanco County. Although the orange spines are reminiscent of H. peigleri in the guide, I have not seen the red intersegment coloration in peigleri (at least in the images I have seen)."

A chrysalis also on the arbor, probably a Gulf fritillary since there are passionflower vines nearby.

"GET YOUR CAMERA!" James hollered again today. "Got a caterpillar for you!" "Is it ALIVE?" I asked. Yes, James said. Resembles a lichen, eh?

And boy, was it! Whenever we nudged it, it flipped and hurled itself like a jumping bean. It also released some fluid. 

Thanks to experts at Bugguide.net, I now know that this guy is an ilia underwing (Catocala ilia). 

Week Five: Wildflowers and Wildscapes

The Lady Bird Johnson Wildflower Center welcomes visitors year around.

One of my number one, very favorite places in all the world–except for our wonderful Wildscape here at the Pink House, of course–is the Lady Bird Johnson Wildflower Center in southwest Austin.

The 279-acre complex features about 650 native Texas species of plants mostly from the Hill Country region. I’ve visited the center in years past (as recently as January) and always get so energized when I see natives growing so beautifully and seemingly carefree. Who needs ornamentals and lawn grass? More so, I celebrate the endless habitats provided there for wildlife.

Week Five of our Master Naturalist training with the Highland Lakes chapter–held at the wildflower center–covered our vanishing state’s species and landscapes for wildlife.

Our morning began with a lecture by Flo Oxley, the center’s former director of plant conservation and education (she plans to teach full time now, I think).

“When a plant is listed as endangered, we still have some time,” she said. “I like the idea that it’s a hopeful thing.”

When she asked if we could name an endangered animal, we came up with species right and left: horned toad, Houston toad, salamanders, oryx and many more. However, when she asked for the names of endangered plants, we were so fast with names.

“We draw blanks when it comes to plants,” she said. “They don’t have big brown eyes and fur. You can’t wrap your arms around a sunflower. That’s called ‘plant blindness.’ We see plants, but we don’t.”

North America has more than 20,000 native species plants. Globally, there are 300,000 plant species with another 250,000 to 300,000 yet to be discovered and described.

Currently, “30 percent of our world’s flora is at risk of extinction,” Oxley said. “Right now, at this minute, a plant has gone extinct. Right now, we’re experiencing the world’s greatest loss of species. And it’s all human driven. We’re worse than the asteroid that hit Earth 65 million years ago!”

Of the 700-plus federally-listed endangered species, 61 percent are plants, she said. “We’re not treating the root cause of the problem–loss of habitat,” she stressed.

According to Oxley, one in five native plant species in North American are declining, threatened or nearly extinct. “Why should we care? Aldo Leopold said it best: ‘When you’re tinkering with nature, keep all the parts,’” she said, paraphrasing the great late naturalist. “Another one of my favorite nature quotes is from naturalist John Muir: ‘No matter how you pick it apart, everything in nature is connected, and we’ve forgotten that we’re connected, too.’”

Many threats endanger our natural world: urbanization (YES YES YES); agriculture and ranching; recreation; introduction of nonnative species (plant and animal); over collecting from the wild; PLANT BLINDNESS.

Cool factoids: The 5,000 species of native plants in Texas comprise 25 percent of all North American plant species! Plus, one percent of Earth’s flora occurs on the Edwards Plateau. (Another reason to care about our native species!)

In addition to 23 endangered plant species and five threatened, Texas also has 204 species of concern. “These are plants we know that are in crisis,” Oxley explained. “Do they need to be listed as endangered or threatened? We don’t have the resources or information to know for sure.”

For more info on our plant species in crisis, visit

What can YOU do? “Educate yourself. Ask questions. Be vocal. Set an example. And GET INVOLVED,” Oxley advised us.

“Our home gardens will be the last refuge for some of these plants,” she added.  

A fresh flower display helps visitors recognize native wildflowers.

Big red sage (Salvia pentstemonoides), extinct in the wild.

Flo Oxley shows Pat a Texabama croton (Croton alabamensis var. texensis).

After a brief break, Oxley led us on a tour of the center’s Research Building. Inside, she showed us the Herbarium, where approximately 3,200 plant specimens are documented and preserved. The specimens represent 200 families, 500 genera and nearly 1,000 species, she said.

In the seed lab, she explained how volunteers clean and process collected seeds, using sieves and a special aspirator. “Timing is everything,” Oxley said. “You’ve got to collect them as they’re dispersing and process them properly, then get them into the freezer.”

A third component in the Research Building is the center’s Seed Bank, where seeds are preserved in short-term plastic bins, medium-term in refrigerators and long-term in a large Kenmore freezer. “The most successful seed bank in the world is an empty one,” Oxley noted. “But this is a hedge, a safety net, to grow back species. For example, we have seeds here for Bastrop that will help people there reseed and reintroduce their native species.”

Inside the center's Herbarium.

Machines used to clean and process seeds.

The big freezer that stores seeds long term is RARELY opened.

A custom-made seed chamber where seeds are stored until they're processed.

The center's Demonstration Gardens.

The red blooms are Wright's penstemon (Penstemon wrightii)...breath taking!

Kelly Conrad Bender is the co-author of Texas Wildscapes: Gardening for Wildlife.

After an hour lunch break, Kelly Conrad Bender, an urban wildlife biologist (who specializes in ecosystem management) with the Texas Parks and Wildlife Department, discussed landscaping for wildlife (a favorite topic of mine!).

Basically, a wildlife habit requires: food, water and shelter.

“Our traditional lawns were an attempt to emulate the old estates of Europe,” she said, referring to typical yards planted with ornamental trees, shrubs and grass. “They take out the diversity of native species to make a unique appearance. They’re as sterile as a parking lot.”

When landscaping for wildlife, keep two keys in mind: plant a variety of species and create layers (canopy, understory and groundcover). 

Why choose native species? They’re well adapted, disease and drought resistant, and co-adapted with native wildlife species, Bender said.

For more information on Wildscaping and how to certify your property as a Texas Wildscape, visit TPW's website: Texas Wildscapes.

Our last activity for the day was a tour of the gardens with Master Naturalist Linda O'Nan with our Highland Lakes chapter.

One of the state's native passionflower vines.

I thought damianita (Chrysatinia mexicana) was really pretty.

I have to insert this somewhere: it was my Fifty-Again (for the third time) birthday! What better way to celebrate (since I couldn't be with my husband and mom) than to spend the day at the Wildflower Center! Celia took these three pictures for me. And before classes started in the morning, Sammye led everyone in a "Happy Birthday" song to me. I was so touched. (Yeah, Ken, I'm sentimental that way!) Later, Ed serenaded me with a solo rendition ... funny!

At home, my sweet husband surprised with me a yard-art praying mantis that had just recently "caught" a bee!

And on my way home, look what found me at the Sol'stice Home and Garden Expressions nursery...a damianita, a birthday gift to myself!

 Ed and Celia, my classmates, said I could post their photo...

NEXT WEEK

Our class curriculum takes us to the Flying X Ranch, where we'll learn about rainwater harvesting and native grasses of the Hill Country.