War on Sahara Mustard

Yes, sewer construction is over, the holes have been covered and the streets have been resurfaced, but the project left behind an insidious reminder. The digging up of practically every street in Los Osos/Baywood Park engendered a huge crop of Sahara mustard, Brassica tournefortii, an invasive plant.

Celebrate Los Osos has taken on an ongoing project to eradicate this plant.

Numerous old-world mustards have invaded North America and of these, Sahara mustard is the newest and by far the worst. It is a monster! It is a robust, fast-growing, drought-tolerant winter annual that prefers sandy soils. The basal rosette of divided hairy leaves can span three feet in wet years. The nearly leafless flowering stems branch profusely and grow to a height of about two feet creating the appearance of a shrub from a distance.

These highly invasive plants especially thrive in disturbed soil. And they self-pollinate, so one large plant can produce 16,000 seeds. Sahara Mustard easily and quickly outcompetes native plants that nourish our wildlife. Without native flora, we lose our native fauna.

One mustard plant can produce 16,000 seeds. Devil’s thorn, another invasive plant, also seeds prolifically, and it grows a deep taproot, which needs to be pulled up or the plant will return.

As shown below, the plants have rough, hairy leaves that get smaller as they move up the stem. The plant can be as short as 4 inches or as tall as 40 inches. The flower is tiny, pale yellow, and composed of four symmetrical petals.

2016

We began at the end of February 2016. For three weekends, CLO volunteers ventured out, in sometimes inclement weather, to pull out Sahara mustard plants in various lots and along roadsides. Many large trash bags were filled and disposed of.

2017                             

On Jan 28, 2017, the second year of our War On Sahara Mustard was launched with 32 volunteers meeting at the Red Barn. Orientation included an introduction to the plants, location assignments, distribution of trash bags, and location of the dumpster.

The groups worked hard and succeed in filling the dumpster with bags bulging with the invasive weed. The further good news was that the sites of weed pulling in 2016 resulted in very few, and sometimes no, new weeds this year at those sites. The strategy was working, with lots of hard work by the volunteers.

This year’s volunteers included:  Steve Best, Jen Carroll, Faylla Chapman, Cindy Dietrick, Anthony Frere, Jennifer Frere, Adrienne Frere, Eric Heeren, Lilah Green, Annette Kennedy, Sierra Kocian, Tony Lindstrom, Laurie McCombs, Susan McTaggert, Richard Mazehov, Kathleet Mittugh, Pandora Nash-Karner, Ted Oliver, Leslie Rotstein, Skip Rotstein, Tony Salome, Bonnie Thompson, Lynette Tornatsky, Andy Wallace, Alicia Welchert, Tony Wiech, and Annie Wiech.

We thank them all and apologize for not getting the names of everyone.

2018                                       

Starting February 17, 2018, a third Sahara mustard harvesting was launched, with a new invasive weed added, devil’s thorn.

CLO’s director, Pandora Nash-Karner, oriented the group to identify the plants and removal techniques.

Sahara mustard and devil’s thorn are highly invasive weeds that outcompete our native plants. Our local birds and animals depend on native plants and the native insects they attract. Even your dog will thank you for pulling these weeds out of your yard!

Devil’s thorn seeds can get between your dog’s toes, causing a great deal of pain—and will readily puncture a bicycle tire.

Both plants are relatively new to our town, and there is a very good probability that they can be eradicated before they grow out of control. We need your help before they infest the Green Belt, the Elfin Forest, Sweet Springs, and Montaña de Oro.

Left unchecked, Sahara mustard will eliminate every other plant in its path.

Photos by Pandora Nash-Karner

This year’s volunteer weed pullers included; Bob Conlen, Jillian Dubois, Susan Gordan, JoAnn Hansen, Kathy Hennekey, Mike and Judy Miller, Melissa Mooney, Pandora Nash-Karner, Cindy Roessler, Colleen Stuart, Bonnie Thompson, Lynette Tornatzky, John and DeAnn Troutner, Alice Welchert, Suzanne Werner, Mimi Whitney, and Marilyn Wills: and about an additional dozen who did not sign in, we thank you also.

Funding for the event was provided by Morro Bay National Estuary Program.