The Sahara mustard is an invasive plant native to the Middle East. It was introduced to Southern California sometime in the late 1920s, inadvertently hitching a ride with the palm trees imported from northern Africa when the Coachella Valley’s now thriving date industry was just beginning.
In 2005 researchers from the University of California Riverside Campus (UCR) Center for Invasive Species Research Department (CISR) and volunteers from the US Bureau of Land Management set aside a series of 1/4 acre naturalized plots. On half the plots Sahara mustard was removed by hand-weeding; the other half of the plots were left alone to measure the effect of Sahara mustard.
Results were dramatic. On control plots containing the mustard, native wildflowers germinated in numbers similar to those in the weeded plots, HOWEVER underneath the dense canopy of Sahara mustard the native wildflower plants grew taller, putting energy into height growth, and produced very few flowers or seeds. There was a 90% reduction of numbers of flowers and seed pods… 90%!
Measurements on the plots continued to determine whether the effect of weeding Sahara mustard would last more than one season. Up to 2 growing seasons after hand-weeding, without any further treatments, there were still, albeit slightly, more native wildflowers and less mustard on the plots that were weeded in 2005.
In the Coachella Valley the Sahara mustard densities can reach proportions as high as 300 plants per 11 square feet. Yikes! There is no need to do any math here. If we do not hand-weed mustard the annual native plant seed bank will become increasingly depleted and native wildflowers will become increasingly scarce as Sahara mustard becomes more dominate and takes over the landscape. (cisr.ucr.edu)
Now, hand-weeding mustard is not in our job description on the Preserve, but somebody’s gotta do it! So I start going out with the Preserve Manager, Ginny, several mornings a week to Moon Country to pull mustard.
Just between you and me, I discover that I actually enjoy pulling mustard! It’s a quiet, meditative, repetitious experience. It’s addictive. Once you spot and pull your first Sahara mustard weed you can’t stop spotting and pulling more. And even if we only make a dent in the density, it’s a good feeling lugging a filled trash bag or 2 over my shoulders and looking back over the areas cleared, knowing I am helping to preserve the Preserve.
Besides, I get to visit places that are off the beaten path. Shhh! Please stay on the trails! (Unless you want to pull mustard WITH us…)
Sometimes I ride with Ginny in the pickup truck out to Moon Country where the wash is wide enough to navigate through. But a real treat is riding in the newly purchased Kawasaki MULE (Multi-Use Light Equipment) UTV (Utility Task Vehicle).
Today I literally run into one of my favorite flowers while bending over to pull a mustard weed.
Spectacle pod is one of the first wildflowers to bloom on the sand dunes. The white flowers consist of 4 petals and 6 stamens characteristic of the mustard (brassicaceae) family. So, yes, spectacle pod and Sahara mustard share a family tree, but let’s just say that’s all they have in common. (Jon Mark Stewart, from his book Colorado Desert Wildflowers)
What tickles me about this plant are the round, spectacle-shaped fruits.
Since May 2019 Simone Pond has been undergoing a restoration process towards the reintroduction of the desert pupfish, cyprinodon macularius.
The desert pupfish was listed as federally endangered in 1986 due to habitat loss and modification, pollution, and predation from non-native species. Establishing refugia habitats, such as Simone Pond, is part of the Federal Recovery Plan to support and recover the population.
The introduction of several non-native species, such as red swamp crayfish (procambarus clarkii) and tilapia (oreochromis aureus), ultimately led to the demise of desert pupfish in Simone Pond.
Both crayfish and tilapia have rapid reproductive cycles and can produce numerous offspring, which makes them difficult to remove. Furthermore, crayfish can burrow, walk on land, and persist out of water. Consequently, previous removal projects have proven unsuccessful.
As of January 2019, the Center for Natural Land Management (CNLM) estimated there were over 23,000 crayfish and 4,000 tilapia in Simone Pond! That same month a new restoration plan was launched. Through a grant, an aquatic biologist was hired to spearhead this effort which included unique and integrative approaches to remove the invasive species: trapping, draining the pond, electrofishing, and the application of naturally-derived pesticides. (coachellavalleypreserve.org)
Ginny takes me on a private tour of the fenced off Simone Pond…
Still a breathtaking sight, even cleared of reeds and with remnants of blue-green pesticide spray on its banks…
The forest of mighty Palms…
A makeshift watering hole for the wildlife…
And finally the water reflected in the pond creates this dramatic illusion with the palm skirts.
The perks of pulling mustard outweigh the bending, sweat, and lugging of cumbersome garbage bags filled with weeds and seeds!