The End of the 8-Month 2020 Thistle Removal Season

Thistle’s worst nightmare: my right hand. Thistle’s second worst nightmare? My left.

I’m calling it. Recently I finished clearing one of the last two meadows left with Yellow Star thistle (along Norrbom Road), and since it is drying out and becoming difficult to remove completely, I’m giving it up for this year. We started in mid-January. That means I’ve spent over 8 months going out nearly every day for an hour each day to clear first Italian thistle, then Yellow Star, except for the few “vacations” we’ve had in this time of shelter in place (to be clear, I was going out to pull thistle even during the shutdown of public properties, as I had permission to do so).

The good news is that we are winning. I’ve never cleared this particular meadow before, which means that other sites had been cleared so that now I can turn my attention to the two remaining meadows that still have Yellow Star thistle. Only one of them remains uncleared this season. I fully expect that within three years we will be able to state that there is no Yellow Star thistle to be found from Schocken Hill in the east (Sonoma Overlook Trail’s eastern border) to 4th St. East (the Montini Preserve’s western border). If you have recently visited other public lands in this valley perhaps you can appreciate the import of that statement.

Italian thistle remains a different matter, especially on the Montini Preserve, where it remains prevalent. We had our hands full simply pushing it back from the trail this year. Also, Italian thistle seems to be coming in where we have been clearing Yellow Star thistle, so we need to be vigilant in those areas. The essential problem is that Italian thistle will grow anywhere, whereas Yellow Star thistle prefers open meadows, which limits its coverage.

As I close out the thistle season, I will move to Scotch broom. I even bought a special tool to help pull the largest, most established broom plants. There is one rather bad patch of it on the Sonoma Overlook Trail property, but that seems to be about all of it except for the adjoining Sonoma Cemetery. The issue is that it adjoins the Overlook Trail property, so it should also be removed to protect the trail property.

One other species deserves mention, as there has been a patch of Bellardia strung out along the very top of the Overlook Trail that Richard Dale, Executive Director of the Sonoma Ecology Center, cleared out this year. These are by no means all of the invasive species, but they are some of the most problematic, and certainly those that present an existential threat to these properties if left unchecked.

Later I will provide a final report on the 2020 invasive species removal season, but I thought that the end of “thistle season,” which has so far comprised the bulk of our efforts, was worth noting.

The Last Gasp

Long about now, I get a little frenzied, as I know that the “thistle season” is drawing to a close. To be specific, as we slouch toward August, our chance to pull invasive thistle begins to wane, as it begins to go to seed and pulling can lead to seed dispersal, which we definitely don’t want. By now the Italian thistle has long since dried out, making it a dubious target, although potentially still fair game if you’re careful. But by this time our focus has shifted to the Yellow Star thistle (YST), which is blooming, and will continue into August. And there is still plenty to get, although on the main part of both the Overlook and Montini properties we are looking pretty good.

The place that isn’t so great for YST is along Norrbom Road — specifically, the water tank properties. That is where I’ve been focusing my efforts in recent weeks. Primarily, I’ve worked on two goals:

  1. Reducing the physical extent (drawing in the boundaries), and
  2. Reducing the seed load (pulling the large, most productive plants that are most likely to spread seed).

I’ve essentially cleared it along the road from the Overlook parking lot turnoff to the Rattlesnake Cutoff crossing, but north of there still needs a lot of work. This is essentially from the road to the fence. Beyond the fence is another story. There is still so much left to do there. I’m thinking of organizing a workday, which if you know me you know how desperate I’ve become. Organizing an event is one of my least favorite things to do.

A lot of what I’ve been pulling has been very small (see the picture). I know it’s because any thistle coming in this late in the season has a physical awareness that it needs to bloom right away, and not try to grow big. Nonetheless, I can’t help thinking about the Nazis, sending in their youth in a last gasp of trying to save the Third Reich from inevitable defeat. I like to think that the defeat of invasive thistle on these two properties is just as certain. The thing is, it isn’t certain until it is, and we are still a long way away from that.

 

The War Begins Anew

A young Italian thistle, which can grow to be over 6 feet tall.

Today I spotted the first Italian thistle plants (see picture) of the 2020 invasive species removal season — or what I simply call “thistle season,” as the species we’re most focused on at the moment are the Italian and Yellow star thistle. These species are fully capable of taking over entire ecosystems and driving out native species and even wildlife. Thus we fight.

Thistle season has grown to last from the end of December, with the early onset of Italian thistle (slightly later this year), to well into August with the Yellow star. That makes thistle season nearly 8 months long, with only 4 months off. It doesn’t mean that we’re out there every day, mostly hand-pulling the weeds, but it means that every day we can starts to add up to a real difference. As it is, we’re witnessing a decrease in the volume and extent of Yellow star thistle, since we’ve attacked it for close to a decade. It’s even gone from some areas. But Italian thistle has essentially overrun the Montini Preserve and it is threatening to do the same on the Overlook Trail property. Thus, our recent efforts on Italian thistle have tended to focus on the Overlook Trail — first to eradicate it from the trail verge, where traffic on the trail can spread it, and then to fight it back from the trail into the surrounding areas.

Last year we were successful in clearing it back from the trail, but much beyond that was mostly untouched except for a few select areas. This year we’re hoping to have the time to take the fight further out from the trail, and especially hit some meadows where it hasn’t yet become widely established, such as the Upper Meadow on the Overlook. But the season has just begun, so we shall have to see what we can accomplish this season.

Meanwhile, if volunteering to help us pull these weeds is something that might interest you, I recommend you first read this post: “‘Don’t Look Up’ and Other Lessons from Invasive Species Removal.” We’re not trying to scare you off, really we aren’t, but it’s best to approach this work with your eyes open. Trust me on that. If you’re still game, let me know.

If you don’t wish to volunteer, but see us doing the work when you hike, throw us a wave. Feelings of pity and “there, but for the grace of God…” are also appropriate.

August seems like a long, long way off from here.

 

The 2019 Invasive Thistle Removal Season is Over

The weapon of choice: the glove that pulled thousands of thistles.

I’m calling it. Today was the first day I was out on the Montini Preserve and Overlook Trail properties and was unable to spot a single Yellow Star Thistle plant. So I consider this year’s invasive thistle removal season officially over. And what a long road it’s been.

I started pulling Italian thistle at the end of December, when I could pull it and discard it. Later, when blooms began to form we had to bag it in large contractor debris bags and carry it out. We dumped it beside a dumpster in the cemetery, as requested by City staff. As the season progressed, we moved to Yellow Star thistle while the Italian thistle that we couldn’t get to sadly went to seed.

For our next Sonoma Overlook Trail Stewards meeting I will be giving a more formal and complete report, but here it is in a nutshell:

  • Yellow Star Thistle: Although we are clearly making progress, we may be 2-3 years away from complete eradication, except for along Norrbom Road, which has been completely unassailed so far. However, we have reduced the YST so far that we have now given it a setting of “zero tolerance,” which essentially means we are morally obligated to pull everything we see.
  • Italian Thistle: We only recently started to seriously address Italian thistle, and there is a long, long way to go. The Montini Preserve is all but overwhelmed with it, and removal operations were performed mostly along portions of the trail, largely for hiker comfort. On the Overlook, it was successfully removed from the entire trail, back at least 3-6 feet or more. It remains a substantial problem off-trail, although not as bad as the Montini Preserve. We have assigned a status of “calculated and opportunistic,” which means focusing on minimizing its spread by pushing it away from the trail and attacking isolated pockets elsewhere.
  • Scotch/French Broom: There is a bad section of broom near the cemetery that was unaddressed this year, and it is also encroaching on the Toyon Trailhead from the cemetery. Current status: unaddressed.
  • Tocalote: Tocalote is found in scattered areas across the property, but it’s extent is unknown and it remained unaddressed this year.
  • Bellardia: This is also un-assessed and unaddressed but doesn’t seem to be a major problem yet.
  • Others: un-assessed and unaddressed.

We still need to perform a systematic review of invasive species on these properties, but so far our efforts have been focused on removal of those that pose an existential threat to the existence of a diverse ecosystem. And so far we have our hands more than full simply trying to stem the tide.

Chasing the Star

Long-time sufferers of reading this blog know that we have been fighting a battle against invasive species. Not really a battle, actually, but a war of attrition. We just hope we can outlast them.

This season I made a rookie mistake of judging the extent of the Yellow Star Thistle (YST) too soon in the season. Seeing very little, I allowed myself to drift into a feeling of complacency and accomplishment. Then I went away on vacation for three weeks in July, just returning earlier this week. And wow, what a difference a few weeks made. We are far from out of the woods with Yellow Star Thistle. Yesterday I even had to do the unthinkable — leave some behind. My large contractor’s bag was simply too full. Today I returned and got that patch as well as many others. And that’s why this post.

I know we’re in a long game, and I know how it’s played — perhaps better than most. But anytime you set yourself a big audacious goal you’re running the risk of having periods of disappointment and depression. I’m having one of those now. Don’t worry, I’m not asking for sympathy or encouragement. I know what we’re in for, and I also know I’m good for it, and that this moment will pass, as it always has. But I want to take a moment to acknowledge that when you play the long game you’re going to have these periods of disillusionment, but that doesn’t mean you have to give up. On the contrary, they are to be expected and weathered just like the periods of euphoria and accomplishment.

Also, I know that the years of work are having results, just not as rapidly and thoroughly as I want. But I’ll be back out there tomorrow and the day after that. And YST: I’ll see you next year too, and the year after that. Don’t be late. I won’t.