Chasing LIRA: It Can’t Outrun Greens at Work

It was one year ago when we reported on our Algerian lavender (Limonium ramosissimum, aka LIRA) removal project in the Bay Leaf. At the time, our Greens at Work volunteers were working on five different LIRA locations along the Bay Trail at Point Isabel on the Richmond shoreline. Since the diminishing number of LIRA at those five sites was not keeping us busy enough, we were motivated to add a sixth! By Jove, this site may test our resolve!

On June 25, Drew Kerr of the Invasive Spartina Project alerted us to a LIRA infestation along the riprap jetty at West Stege Marsh. We had observed the purple LIRA flowers amassed along the jetty but were convinced that the area was only accessible by boat. Drew informed us that it was possible to reach the LIRA infestation on foot during a low tide. With fingers crossed and wearing old shoes, we ventured out across the marsh toward the jetty. Treading through an inch or two of water, it was easy to reach the riprap jetty, where we found an astonishing infestation of LIRA in multiple areas scattered all along the jetty. There were virtual “forests” of huge plants full of blooms and surrounded by thick carpets of seedlings. The roots of the large plants were woody and very deep, leading us to believe they had been there for a number of years.

We’ve been puzzled about how LIRA grows. For example, when removing a large single mass of LIRA, the plant’s many rosettes all seem to be fed by a single woody root, and yet many of the smaller plants appear to grow as individual rosettes. Do the older, more mature plants simply create new rosettes as they grow? What happens to the thousands of single plants that make up a significant portion of the infestation? Interestingly, whatever they do as they develop, none of the smaller plants appear to be overwhelmed by the larger plants. They just all seem to find a comfortable space to continue growing.

As we pulled the LIRA out of the soft mud at the first location, we discovered a number of natives: sticky sand spurry (Spergularia macrotheca), California sea lavender (Limonium californicum), pickleweed (Salicornia pacifica), salt grass (Distichlis spicata), alkali heath (Frankenia salina), marsh jaumea (Jaumea carnosa), coastal gumweed (Grindelia stricta), and California dodder (Cuscuta californica).

After the two work parties it took to completely clear the first large infestation, we headed north along the jetty and spent a little time working on the next substantial site. It was easier to remove the plants at that sandy site, but we had to retreat as the waters of the rising tide approached.

At our next work party, we realized we should head south to clean out two extremely large infestations in the mud and on a small gradient that also contained alkali Russian thistle (Salsola soda) and iceplant (Carpobrotus edulis; one of our Mexican volunteers told us iceplant is known in Spanish as Uña de Gato, or cat’s claw). As of July 20, we completely cleared the most southern section and removed all the blooming plants and many of the seedlings on the gradient. We will now head north to begin removing the remaining infestations. We will not be able to eradicate the entire infestation this season and will continue to return until the LIRA is under control.

We’d like to single out Rob Kirby Jr. with a special acknowledgement for his amazing work at clearing trash from the marsh area and along the jetty edge. It can be disheartening to the point of fatigue to see the amount of debris that we humans generate and discard without concern for its impact on the environment. Yet Rob shows up every time and works steadfastly at reducing the amount of garbage that finds its way to the water’s edge. Thank you, Rob!

With thanks to dedicated and talented volunteers (Nancy, Rob, Ricardo, Ivy, David, John, Kimberly, Nina, Jean, Juri, Jim, Doug), we have to date removed an estimated 163,000 LIRA plants and their seedlings from the riprap jetty.

Since we began the project in August 2019, we have removed 229 bags of trash and 325 bags of alkali Russian thistle from all six sites. The chart below describes the estimated total number of LIRA plants removed at each site. At the rate we are going, it won’t be too long before we hit the one million plant mark! Nevertheless, it is apparent that the numbers in the first five sites are decreasing over time—proof that patience and persistence are paying off.

LIRA Plants Removed August 2019–July 2021

— Jane and Tom Kelly, Greens at Work
August 2021