2011 Trip Report - DE Rendezvous -Anza Borrego Wildflowers

Borrego Wildflowers
Leader: Allan Schoenherr
At 9:00 a.m. on Saturday morning 15 cars lined up along Palm Canyon Road ready to search for wildflowers. As most of us knew the display was not as dramatic as it had been in other years, but as documented by Dave Bullock, the Proffitts’ son-in-law, we ultimately saw at least 52 different species. In other words species diversity was quite good but total coverage of the landscape was missing.
We began our search by stopping along DiGiorgio Road where the pavement ends and the dirt road begins. The roadside there exhibited many showy flowers including Desert Dandelion, Desert Sunflower, Arizona Lupine, and Sand Verbena. The question arises, why are flowers so abundant along roadsides, and why are the Creosote Bushes larger next to the road? The answer: Paved roads are higher in the center so water runs off to the sides which greatly increases available moisture for plants. Also, the pavement traps water underneath which makes it available to the roots of roadside shrubs. At this point we also talked about the abundance of non-native weeds, particularly African Mustard that out-competes native plants for water and when it dies fills in with flammable thatch the gaps between native shrubs. The dead material then becomes fuel which enables fire to carry from shrub to shrub, a situation which normally does not occur in desert landscapes.
Next, we moved farther into the mouth of Coyote Canyon and were greeted with blooming Ocotillo and Desert Brittlebush. We stopped at the trailhead for Alcoholic Pass and walked up the trail. This is a rocky region where most of the plants are either water-storing succulents or drought deciduous, dropping their leaves in the dry season. Here we observed Ocotillo with their red tubular flowers which are pollinated by hummingbirds. We talked about the fact that Ocotillo, in association with irregular precipitation, can gail and lose new leaves several times a year. They also can store water in their stems and carry on photosynthesis with chlorophyll in the bark. We also observed beautiful drought deciduous shrubs such as Indigo Bush and Desert Lavender. We found three species of cactus in bloom; Beavertail, Silver Cholla, and Desert Barrels. We also learned how the stem-joints of Teddybear Cholla jump from a hiker’s foot to the back of the other leg. Here, on the side of a hill, we saw a large number of Bigelow’s Monkeyflowers, and some odoriferous Chias.
On our third stop we walked up a wash at the Desert Garden, a well known stop off point for Borrego lookey-loos. There were lots of flowers here including abundant Desert Dandelions, Pincushions, Popcorn Flowers, Phacelias, Star Flowers and an interesting member of the Carnation family known as Desert Frost or Frostmat. It’s a good thing we had such nice weather, because when the fearless leader scouted the location the day before, the temperature was 104 degrees. One of the highlights of this stop was pursuing a Desert Iguana, a desert lizard who is able to tolerate a body temperature of 114 degrees. It was approaching lunch time so we drove back to town and ate lunch at the picnic tables in Christmas Circle.
After lunch most of the participants traveled to Hawk Canyon, a scenic location marked on one side by uplifted colorful lake beds, and the other side by block-jointed granite boulders. This location is geologically interesting because the East and West Butte portions of Borrego Mountain are offset sideways, leaving different geological formations on each side of the Canyon. The east side of Hawk Canyon has been dragged nearly a mile farther north by strike-slip motion along the San Jacinto Fault. We saw different wildflowers here. There were two kinds of Poppy; Parish’s Poppy and the tiny-flowered Little-gold Poppy. We also saw two kinds of Evening Primrose; Sun Cups and another tiny-flowered species, California Sun Cups. A highlight here, on a hillside of clay soil, were groups of Desert Five-spots and Blazing Stars. Out in the wash we observed Smoke Trees and Ironwoods, the seeds of which are carried along with sands and gravels during heavy thunderstorms typical of the Colorado Desert. This grinding action of the rocks cracks the seed coats, enabling water to enter and stimulate germination in the wet soil only when abundant water is present. After Hawk Canyon, a portion of the group went on to explore the Goat Trail. Some visited the nearby scenic slot canyon, and others went of to view the metal sculptures. Everyone seemed to get back in good spirits in order to enjoy the evening festivities.