Imagine what Southern California looked like before European settlement. Accounts in the 1800s indicate that in areas such as Los Angeles wildflowers may have been the dominant vegetation type.

Henderson Canyon Road near Borrego Springs. Hendrickson.
This photo was from an area near Borrego Springs northeast of San Diego in Anza Borrego Desert State Park. If rain comes at the right time, wildflowers bloom prolifically. The wildflowers were one reason why we visited the area this past March.
A new factor, however, threatens these remnant stands of wildflowers in places like Borrego Springs. Sahara mustard, an invasive drought tolerant winter annual, has spread across the desert west.

Sahara mustard infestation on Henderson Canyon Road near Borrego Springs in 2010. Hendrickson
It has dramatically affected native desert wildflowers including those in the Borrego Springs area. It has turned beautiful fields of wildflowers into a monochrome of green as in the photo at left.
After a rush of growth of Sahara mustard in the Borrego Springs area, community members have faced the loss of another remnant of Southern California’s natural history. Moreover, the loss would not just be one of natural beauty and ecological diversity – the economic repercussions for the Borrego Springs area have already been felt as highlighted in a recent article in the Los Angeles Times.
Fortunately, the Borrego Springs community has refused to concede the fight to the mustard. They formed the Sahara Mustard Weed Eradication Task Force in 2010. With over 30 representatives, the Task

Volunteers removing Sahara mustard in Borrego Palm Canyon
Force is a diverse group of individuals, businesses and governmental entities. Sam Webb is one representative. He and his wife Astrid “retired” in 1998 and moved permanently to Borrego Springs. They were elected honorary mayors of the Chamber of Commerce in 2004-05 and have been active in organizing concerned businesses and have been out in the field beating back the mustard.
Larry Hendrickson on the staff with California State Parks has been working with the Task Force. He has trained “authorized temporary volunteers” who can work within the Park to tackle Sahara

Larry Hendrickson training volunteers in Borrego Palm Canyon
mustard. He has enlisted the help of the National Sierra Club, AmeriCorps, Explorer Scouts. On behalf of the Coalition he has sought assistance from road maintenance authorities to limit the spread along vectors such as highway shoulders and ditches.
When I talked with Larry on our visit to the area in March, he was out working with a Cal Fire inmate crew (low level offenders who typically fight wildfires). Larry says that after eight years of weeding, he has seen less mustard and more native wildflowers in wet years (although he was careful to note this assessment was only based on observations).
As with so many established invasive plants, however, eradication of Sahara mustard is impossible with existing technologies and knowledge. Why, then, keep pushing back against it?
Chris McDonald, Natural Resource Advisor with the University of California, Cooperative Extension says this about the work of the Coalition: “They demonstrate just how beautiful Borrego Springs can be when Sahara mustard is removed and when there is sufficient rainfall. Their work also gives the community a sense of hope that it really is possible to bring back the wildflowers.”
Moreover, stemming the tide – even if just a little – gives researchers (and just as importantly, ecosystems themselves) time to respond. For example, McDonald is doing studies comparing removal methods for Sahara mustard and research on Sahara mustard seeds in the soil seed bank. McDonald has also formed the Sahara Mustard Consortium with a website that provides information on Sahara mustard and links to all sorts of webpages on wildflowers. I especially urge you to read McDonald’s webpage on the natural history of wildflowers in Southern California.
Visit Borrego Springs – regardless whether the wildflowers are blooming! On our visit, we stayed for about a week. We had a wonderful time! The residents of Borrego Springs are warm and welcoming. We didn’t get to see the sea of blooming wildflowers. (Lack of timely rains depressed blooming of both native annuals and Sahara mustard.) Nonetheless, we enjoyed gorgeous hikes around Borrego Springs. Cacti and perennials were in full bloom, and they were spectacular.

Barrel Cactus. Newman