Central California Invasive Weeds Symposium: Part 1 - The inevitability of chemicals

A slide from a talk by Richard Miller, Pest Control Advisor, Specialty Programs, Dow Agrosciences, LLC (used with permission)
Having gotten involved this year in the urgent removal of stinkwort (Dittrichia graveolens)  around our county, I decided to go along with some weed-whacking buddies to the 15th Annual Central California Invasive Weeds Symposium that took place on November 7, at Paicines Ranch near Hollister. (I'll post about Paicines ranch separately).

It was an eye opener to me. I felt like a babe who had just wandered out of the woods.

The acceptance of herbicides is universal, with talks featuring  projects where they were used, and sessions on safety and equipment management. You can see the lineup on this page.

But the evidence is in.

If you want to get rid of let's say large infestations of yellow star thistle on wild lands, you gotta burn to remove thatch, and spray with a Dow Chemical product like Milestone or Transline. Talk after talk included use of these products. I had just about known about this out of the corner of my minds' eye, and here it was up front and center.

Here's the summary of the talk by the very pleasant representative of Dow Chemicals, Richard Miller:
Selective Removal of Invasive Weeds & Restoration of Natural Areas Using Growth Regulator Herbicides.
Partnerships between weed workers, volunteers, product manufacturers, researchers, landowners, and government are critical to successfully address invasive weed issues. Weed workers can benefit from a better understanding of which herbicide to choose when selecting one for treating either of the veldt grasses, Cape ivy, perennial pepperweed, yellow-star thistle, or the various woody broom species. Discussion will include the pros and cons of using Milestone, Transline, and various Garlon formulations on these and other weeds of interest. Rick will address how growth regulator herbicides from the pyridine family work and considerations regarding how to effectively and safely apply them and what to watch out for as far non-target species will also be discussed.
I have many inchoate thoughts about this that I need to work on. I also have information to sift through about the selective impact of these chemicals and the limited time they are toxic and so on. I'd like to hear from other voices.

One reason I went was to hear the talk on Stinkwort control, by Rachel Brownsey, Restoration Ecologist, ESA Biological Resources and Land Management, and here is a slide on that:

Combination of hand pulling and pre-and post-emergent treatments advised for large Stinkwort infestations
No there's no getting away from chemicals it seems. We created a mess and to get out of it - I hope we are not creating a different sort of mess.

Ken Moore was the keynote speaker. He's the one I've been working with on hand-pulling Dittrichia. He is a person with some characteristics of an old testament prophet.

Ken Moore, Weed Warrior

 He talked about the heart and soul of a place that lives within you. It was a wonderful talk about tending the wild, old fashioned ingenuity, and stick-with-it-ness. He did his "tool talk" outside to a goodly gathering interested in hand-pulling techniques. Ken is not anti-chemical either, rather he is an advocate of boots on the ground hand work — and not reaching for the chemical spray by default.

And our own CNPS weed warrior Linda Brodman gave an inspiring presentation about her boots-on the-ground Habitat Restoration Team who use hand-pulling techniques in botanical hot-spots around the county. Her talk was on the 10 years of French Broom removal the CNPS restoration team has done at Quail Hollow Ranch, which is in the rare Sandhills habitat near Felton - a wonderful place to hike made more wonderful by the even increasing absence of French broom.

Which leads me to a parting thought - I  sympathized with Dean Kelch, a botanist with California Department of Food and Agriculture, who said that weed workers have to get better at not only measuring their success so as to improve on it …

Dean Kelch talks about measuring weed control effectiveness
... but also better at celebrating their successes —and indeed, how do you celebrate the wonderful absence of something?


Diana Studer said…
I see the stumps of Port Jackson wattle painted blue with weed killer, as they tend to coppice.