The Coronado National Forest spans sixteen scattered mountain ranges or “sky islands” rising dramatically from the desert floor, supporting plant communities as biologically diverse as those encountered on a trip from Mexico to Canada.
Experience all four seasons during a single day’s journey. Enjoy spectacular views from the mountains, wander through the desert among the giant saguaro cactus and colorful wildflowers in the morning, linger over lunch beside a mountain stream or lake, and play in the snow all before the day’s end.
- From “Welcome to the Coronado National Forest,” U.S. Forest Service
I recently attended a conference in Oracle, Arizona. Oracle lies on the desert floor at the foot of Mount Lemmon, the highest peak in the Santa Catalina Mountains, just to the east of Tucson, Arizona.
Oracle is about 3,100 feet higher than Phoenix, where I live, so its climate is different, a little cooler. Snow actually fell in Oracle during the conference, but it started melting by midday. The peak of Mt. Lemmon is another 4,600 feet even higher. The peak of Mt. Lemmon is covered with snow during the winter when I visited. From some views of the mountain from the north, one can literally see a snow line.
I took some pictures along the road from Phoenix to the Oracle area on Arizona State Route 79 (SR 79). These are illustrations of sky islands rising above the Arizona desert.
In this picture, a sky island rises up from the desert floor (background left). I don’t know the name of these mountains.
Three species appear here on the desert floor. What looks like poles in the background are Saguaro Cactuses (SWAH ro). The shrubs in the foreground and scattered elsewhere are Creosote Bushes. They give off the smell of creosote, especially when it rains. Hence their name. Scattered around the landscape are Teddy Bear Cholla (CHOY ah). Farther to the north, along SR 79, the landscape is crowded with Teddy Bear Cholla. They looked like a forest or plantation in the desert. It wasn’t safe for me to pull off the road to take a picture, though.
The memorial to the actor Tom Mix (1880-1940), about 18 miles south of Florence, Arizona, is located along SR 79 where he was killed in a car crash. His car went off the road and landed in a wash (what Wikipedia calls a gully) killing him.
The next two pictures are from a roadside picnic table 23 miles south of the Tom Mix Memorial and not much more than a mile from Oracle Junction and the end of SR 79.
Cholla and Prickly Pear cactuses still grow at this elevation. I don’t know the identity of the tree to the left in the mid-ground or the shrub in the lower left foreground. There are no Saguaros or Creosote Bushes here.
Prickly Pears grow at even higher elevations. Cholla’s range has ended, somewhere between here and Oracle, though.
Farther north along SR 79, around Florence and northward, the roadside looks like a wild roadside in Phoenix. Flowering Lupines (LOO pinz) line the road, and a few Brittlebushes appear along the roadside. The following pictures are not from my trip. It was unsafe to stop to take pictures.
Brittlebushes have been flowering for a little while, since late February. If you drove Interstate 10 between Phoenix to an exit for Oracle at this time of year, you would see flowering Brittlebushes lining the shoulders of the highway and peeking out from under guardrails.
I recently transplanted a wild Brittlebush into a decorative flower pot. The third try is doing well. I used soil that was “seasoned” in my complex’s landscape dump. As common as Brittlebush is, it is still lovely. It has silvery-green leaves. It fills my pot. It’s unlikely to grow much larger than it currently is, though. I doubt that it will ever flower.
One peculiarity of both Lupines and Brittlebushes is that they grow in disturbed soil. Both are native plants, and I’m under the impression that native plants don’t grow in anything but relatively pristine soils. In Northeastern Illinois where I’m from, native seeds rarely germinated in disturbed soil. Once a prairie has been plowed, it doesn’t grow back without massive human intervention.
Dandelions, weed grasses, and invasive Buckthorns colonize disturbed soil in Northeastern Illinois. A succession of some tree seeds takes root. Ashes, Silver Maples, and Honey Locusts are relatively quick to sprout when the soil has begun to heal if the immediate environment is suitable. By heal I mean acquire a range of microbes that native seeds need to germinate and grow. Generally, plants, even native ones, have to be grown in nurseries before they are transplanted into new landscapes.
My parents’ landscapers in the middle 1950s planted inexpensive native shrubs in the backyard as hedges. Two kinds failed to grow, one sooner and one later. The ones that failed were never replaced. The area of one clump was taken over by invasive Buckthorns. I planted invasive Wintercreeper slips as a ground cover where the other clump of shrubs had been. These thrived. As wild native seeds blew in, they germinated and grew to their natural heights. The Wintercreeper had healed the soil. All these plants, including the Wintercreeper, lived well together. I didn’t touch the area other than to cut back and thin the Wintercreeper. Fifty years later, the native shrubs were doing well if a little misshapen. Then in 2004, we siblings sold the house on behalf of Dad.