Saguaros & Rock Art

To most of the world, these prickly giants symbolize the American West. To me, they seem like a large family, gathered together after a long time of absence, merrily chatting away. Their posture, their gestures – expressive, daring, even obscene, the way they lean on each other; I feel at home among the Saguaros, never mind our differences (mainly in size).

We traveled a long way to meet them, because they gather exclusively only in small parts of the U.S. West; Tucson is one of their favourite spots, especially for the ”younger” among them.

Did you know that their branches begin to grow when saguaros reach 60 to 75 years of age? That is for those growing in the Saguaro National Park; in areas of lower precipitation, it may take up to 100 years before arms appear.

An adult saguaro is generally considered to be about 125 years of age. It may weigh 8 tons or more and be as tall as 50 feet. The average life span of a saguaro is probably 150 – 175 years of age. However, biologists believe that some plants may live over 200 years. The estimated number of saguaros in the Saguaro National Park is 1.8 million.

With such a long lifespan, it is only fitting that Saguaros would have chosen to gather here, in a land dotted with archeological sites spanning more than 8,000 years of prehistoric and historic-period occupation.

One of these prehistoric sites, accessible to visitors, is Signal Hill; a small hill with petroglyphs created by the prehistoric Hokoham people on the boulders that cover the hillside. Saguaro National Park, Tucson, AZ

January 29th, 2019

Biosphere 2

In 1991, a group of four men and four women researchers entered the sealed mini-world of Biosphere 2,  an ecosystem complete with wilderness areas, a farm, a rain forest, a desert, wetlands, and even a coral reef in a 25-foot-deep, 150-foot-long ocean. They would live, work and study inside this bubble for two years.

Biosphere 2, was then ”the greatest experiment ever conducted in ecological self-organization, revolutionized the field of experimental ecology”. It has not been repeated on this scale, since.

Today, Biosphere 2 forms part of the University of Arizona and consists of seven model ecosystems, a team of multidisciplinary scientists, a broad science education and public outreach program, and a modern conference center. The seven model ecosystems are: 1) a mature rain forest with over 90 tropical tree species, 2) a 2600 m3 ocean, 3) forested swamps dominated by mangrove trees, 4) a tropical savanna grassland, 5) a 1400 m2 coastal fog desert, 6) three desert hillslope grass-shrubland landscapes, and 7) Biosphere 2, its campus, and associated buildings and facilities serve as a 162,000 m2 model city and urban ecosystem. Its mission is to serve as a centre for research, outreach, teaching and life-long learning about Biosphere 1 – our planet, its living systems, and its place in the universe.

You can find out more about this unique, fascinating-turned-controversial project on the Biosphere 2 website, an article on Space.com and a feature by a member of the original team on Dartmouth Alumni Magazine.

Oracle, AZ

January 28th, 2019

Arizona-Sonora Desert Museum

I love cacti. The way they grow to enormous heights in harsh environments where other plants simply dry up and die; the way they preserve water and keep the desert alive; and the way they bloom, producing some of the most beautiful flowers on the planet.

Whether in a ”controlled” habitat like the Arizona-Sonora Desert Museum or in the wild, cacti command respect and admiration in equal parts – and, come to think of it, they can also teach us a thing or two about the virtues of social distancing.

The Arizona-Sonora Desert Museum is a zoo, botanical garden, art gallery & classes, natural history museum, and aquarium all at once, dedicated to the education, protection and conservation of nature in the Sonoran Desert Region.

The David Yetman West Trailhead leads to a 3,9 loop trail of moderate difficulty, with sweeping views of the desert – that is, if you start early enough to beat the heat.

January 27th, 2019