Two Septembers ago, I broadcast a few handfuls of wildflower seed mix in several areas of my garden, hoping for some spring color. Although the mix contained seven varieties of wildflowers, the only wildflowers that germinated that first spring were Desert Bluebells, California Poppies, and Baileya multiradiata, or Desert Marigold. The first two wildflowers are short-lived. They flower in late February and are gone by April. On the other hand, the B. multiradiata comes up late, starts blooming in March, and keeps right on until November.
Found throughout the desert southwest, the B. multiradiata is nondescript, with gray-green wooly leaves. If it weren’t for the flower, it wouldn’t even be noticeable. The flower stalks are quite long, with only one flower per stalk. The flowers are always a pure bright yellow that is difficult to photograph. I’ve probably taken 50 photos of these wildflowers, and just can’t pick up much detail because of the solid color.
This plant is a killer, but it’s a selective killer. A compound (probably hymenoxin) in the plant is toxic to sheep and rabbits, but not cattle and horses. Animals usually know to stay away from toxic plants, but in overgrazed areas or in times of drought, they get hungry enough to chew on what's available. There are some reports of large numbers of sheep lost to this plant.
However, other compounds in this plant are now being tested at Arizona State University for possible use as anticancer agents. So, redemption may come for this common killer wildflower.