09 de marzo de 2020

Coming Soon to the Heard Museum and Sanctuary…

Soon this glossy privet will have an important question to ask itself: "Do I feel lucky?" The date was set for May 16, but I fear that will have to be reset as the Covid-19 pandemic unwinds. But sometime before long I will be teaching my girdling techniques at the Blackland Prairie Master Naturalists' Third at the Heard—their Third Saturday Nature Talks at the Heard Museum. The talk begins at 9:30 a.m. Unless you are a member of the Heard, you do have to pay for admission to the museum, but once you're in the talk and workshop are free.

I will do my best to keep the talk to less than an hour, because the real fun will be when we go outside for a hands-on workshop. Many glossy privets on the grounds of the wildlife sanctuary—as many as we can reach—will learn the peril of the girdling knife on that day.

And so the little privets won't feel neglected, I will bring my suite of uprooting tools, too.

Ingresado el 09 de marzo de 2020 por baldeagle baldeagle | 1 comentario | Deja un comentario

19 de julio de 2019

Glossy Privet: Slayer of Native Shade Trees

Every weekend I walk through the woods of Walnut Creek Metropolitan Park to see how things are turning out for the trees we have girdled and the plants we need to grow in their place. The first weekend of July 2019 I came across a large live oak, shown in the second picture below, that is suffering the damage glossy privets do to larger shade trees:

  • They fill every bit of open space. Everywhere you look up under this oak, you see the leaves of glossy privet.
  • They grow year-round, piercing the oak's canopy.
  • As they grow into the canopy, they shade out—and kill—all the branches they pass by. In this oak, one large branch has died and is hanging in the canopy. Another large branch above it is dying, if not already dead. Both are in the shade of the same four glossy privets.
  • In Central Texas, glossy privets grow to be at least 40 feet tall. That's taller than our treasured live oaks. In fact, glossy privet competes with or towers above every species of tree found in Walnut Creek Metropolitan Park other than our pecans. And it can compete with pecans enough to do serious harm. For example, the pecan shown in the first picture below lost all of its leaves below 30 feet to a dense stand of glossy privet that grew in its shadow. (I'll have more later about the grove where this tree grew.) And for this live oak, it means that the glossy privets are already just as tall and are about to break above it, taking the first bite at the available sunshine.

    Whenever I see a native shade tree in this condition, it becomes an immediate priority. Instead of continuing our march through the woods on the other side of the trail, this weekend we focused on saving this tree.

    In three hours, three of us managed to uproot 27 Nandina domestica and girdle each of the 46 trunks of the 13 glossy privets (Ligustrum lucidum)—that's right; in the same area taken up by the canopy of this one live oak, there are 13 glossy privets—and to reach half of them we had to uproot the Nandina first.

    So today, July 13, 2019, this live oak's chance to recover begins. Over the coming year, I will report on the response of the glossy privets to their girdling and the response of this tree to its increasing access to all the available sunlight.

    Ingresado el 19 de julio de 2019 por baldeagle baldeagle | 2 observaciones | 0 comentarios | Deja un comentario

    18 de junio de 2019

    Diary of the Glossy Privet's Grim Reaper

    Several years ago, I took on the task of eradicating Ligustrum lucidum, also called glossy privet, and other invasive plants rom Austin's Walnut Creek Metropolitan Park. The idea that we could eradicate them is ambitiously optimistic, but I have a feeling we will do far better than just to manage them. Besides, with that goal in mind, I am inspired to keep trying new twists on my techniques for reducing their numbers.

    In this series of posts, I plan to share my observations of the impact of glossy privet on the plant communities in this park and the results—successful and otherwise—of our attempts to bring them under control. Follow me and you will find facts worth discussing, with details to back them up:

    • Glossy privet is so beautiful every spring, and it's a bulletproof evergreen. What makes it the most perniciously invasive woody plant in Central Texas?
    • Not all tree extractors are alike—and it isn't just the trade name that makes the difference. When you put them in the hands of volunteers, which ones work best? Why?
    • How does girdling work? If you have tried and failed, I can show you the way to succeed—and it's probably easier than whatever you've done before.
    • Nature abhors a vacuum. If we can get rid of the ligustrum, what will we put in its place?
    • What other invasive plants are making inroads in the park—and how can we show them the way out?

    One thing you won't hear me discuss is herbicide. At least three friends of mine have died from cancers linked to herbicides. It's better for us and our planet if we don't use them. And even if that weren't my position, I would still have to figure out how to get the job done without them. In Austin's parks, greenbelts, and preserves, volunteers are not allowed to use power tools or herbicides.

    As a teaser, the photo associated with this post shows 55 glossy privets uprooted in 90 minutes by one of my volunteers last weekend. In the background, you can see larger glossy privets that we girdled in the same project. In my posts, I'll follow this and other areas as the ligustrums decline and the new habitat emerges.

    And your comments will always be welcome.

    Ingresado el 18 de junio de 2019 por baldeagle baldeagle | 1 observación | 5 comentarios | Deja un comentario

    Leafcutter ants: An ally against glossy privet

    I have known for some time that leafcutter ants will attack glossy privet. I had even noticed that they seem to do so preferentially. In Austin's Walnut Creek Metropolitan Park, a couple of large colonies seem to be eating nothing else.

    I had not realized that leafcutter ants could kill ligustrums. They certainly strip the leaves, but they don't seem to be able to keep up with the plant's growth.

    All around this huge leafcutter ant mound we can find dead ligustrums. Volunteers working with me have girdled many in the area—but not these. We meant to get to these glossy privets eventually, but the leafcutters beat us to it.

    Perhaps if left to their own devices these ants would never have killed the ligustrums. Perhaps it is that we removed so many seedlings, saplings, and mature trees that the ants overwhelmed whatever remained behind. But they also seem not to have cultivated a taste for other plants in the area.

    If only I could convince them to try Chinese pistache, chinaberry, and giant reed…

    Ingresado el 18 de junio de 2019 por baldeagle baldeagle | 1 observación | 2 comentarios | Deja un comentario