In 2014 we have traveled through 3 distinct types of deserts: The Great Basin, also known as the Basin & Range,extends from eastern Washington and eastern Oregon, through parts of Idaho and all of northern Nevada. It's main plant features are sage brush and other similar brush, pinyon pines and juniper tress. Another desert we've gone back and forth through is the Mojave. The plant which makes this desert stand out is the Joshua Tree. Also common are ocatillo, prickly pear and cholla. Southern Nevada and south-eastern California are represented by the Mojave.
However, as soon as we had driven a few miles south of Hoover Dam, from Nevada into Arizona, we knew we had entered the Sonoran Desert. Why? Because this is where the Saguaro cactus grow. And they were plentiful right away. The Sonoran Desert also includes many varieties of cholla, several varieties of flat "leaved" cacti similar to and including the prickly pear, some ocatillo and some Joshua, many barrel cacti and smaller versions called pin-cushion cactus.
Of the three deserts, to me the Sonoran is the most picturesque and my favorite. We arrived in Tucson on Novemeber 16th and will remain in the area until at least December 19th. Our first destination/venue was on the east side of Tucson...right next to town (right across the main road from Walmart, Dick's Sporting Goods, a hospital, a cinema and many other shops in the area which is called Oro Valley)at Catalina State Park in the Coronado National Forest.
This is a lovely campground with huge camp spaces - not length wise, though that was more than adequate, but side-by-side with the neighbors wise. That is, lots of room in-between. Normal RV parks and campgrounds would have fit at least one more rig in the space between our site and the next.
It is common for a state park to have ranger led and docent led activities. A sampling included a morning bird viewing hike, a hike to an ancient Native American village site, a big-horn sheep hike, a full-moon evening event once a month, guided nature hikes, and the only one I attended - the Knights in Spiny Armor, led by an enthusiastic local citizen. The photos included here are all from the two hour morning walk. Only I went on the walk, as Dan was not feeling well, and in fact, he felt worse for the rest of our time there. We plan to go back and stay again on another occasion so we can take advantage of the wonderful hikes and activities.
About the cacti: Saguaros have a relatively long lifespan. They may grow their first side arm any time from 75–100 years of age, but some never grow one at all. A saguaro without arms is called a spear. A saguaro about 5 feet tall may weigh up to a ton and is about 50 years old. These cacti can grow from 40 to 60 ft tall. They grow slowly from seed, and never from cuttings. Whenever it rains, saguaros soak up the rainwater, expanding their accordian-like sides. The cactus will visibly expand, holding in the water. It conserves the water and slowly consumes it. The saguaro blossom is the state wildflower of Arizona. The night-blooming white and yellow flowers appear April through June and the sweet, ruby-colored fruit mature by late June. The major pollinators are bats, primarily the lesser long-nosed bat, feeding on the nectar from the night-blooming flowers, which often remain open in the morning. Doves and bees appear to be the primary daytime pollinators. The ruby red fruits are 6–9 cm long and ripen in June. Each fruit contains around 2000 seeds plus sweet fleshy connective tissue. The fruits are edible and prized by local people including the native O'odham tribe. The fruits cannot be picked by hand, but must be harvested using a pole (often a saguaro rib like in the photo), to the end of which is attached another pole.
A saguaro boot is the hard shell of callus tissue that a saguaro cactus creates to protect the wound created by a bird's nesting hole.The saguaro responds to the bird's damaging its tissue by secreting a resinous sap that, over time, hardens into a bark-like shell that prevents the cactus from losing fluid and also protects the nest hole by making it waterproof. The bird pecks through the cactus skin, then excavates downward to hollow out a space for its nest. When the saguaro dies, its soft flesh rots, but its woody infrastructure lasts much longer. So does the hollowed-out callus whose roughly boot-like shape gives it the name of "saguaro boot." Several different kinds of birds create nest holes in saguaro cactus. The Gila Woodpecker creates small holes at midlevel on the cactus, where the ribs are far apart. The larger Gilded Flicker drills bigger holes higher up, where ribs are close together, because its beak is strong enough to break through rib tissue.
Barrel cacti of some species easily reach over 3 ft in height at maturity, and have been known to reach 10 feet in some regions. The ribs are numerous and pronounced, and the spines are long and can range in color from yellow to tan to red, depending on the age of the plant and the species. Flowers appear at the top of the plant only after many years. The barrel cacti we saw over and over was the fish-hook barrel.
The fishhook barrel cactus typically grows to a diameter of roughly two feet and a height of three to six feet. The common name comes from the spines, which are thick and hooked. Its flowers are yellow to red-orange and appear atop the cactus fruit during the summer months. The fruits are green when unripe, yellow after the flower dries up, and persist atop the cactus long after the flower is gone, sometimes for more than a year. In adulthood, fishhook barrel cacti generally leans southward, toward the sun, earning it the nickname "compass barrel cactus." I saw many of them doing exactly this leaning while on the Spiny Armor hike. One theory about why this happens is, the afternoon sun is so intense it slows the growth on the exposed side, causing the plant to grow unevenly. Older barrels can lean so far they uproot themselves and fall over especially after heavy rains when the soil is loose. Its life cycle is 50-100 years.
Teddy-bear cholla, stag-horn and pencil cholla, jumping or hanging-fruit cholla, chain-fruit and tree cholla as well as prickly pear are all types of cholla I saw on the hike. There are more than 20 types of cholla in the North American deserts. Cholla is a term applied to various shrubby cacti with cylindrical stems composed of segmented joints. These stems are actually modified branches that serve several functions -- water storage, photosynthesis and flower production.
Like most cactus, chollas have tubercles -- small, wart-like projections on the stems -- from which sharp spines -- actually modified leaves -- grow. But chollas are the only cactus with papery sheaths covering their spines. These sheaths are often bright and colorful, providing the cactus with its distinctive appearance.
Prickly pears are also members of the same genus, but their branches are manifested as pads rather than cylindrical joints.