Our most important nature lesson of the walk had to do with these strange little pictures of dirt.
This deposit of blackish crust on the desert floor is a living growing substance called cryptogamic or biotic desert soil. It is what holds the desert floor together and can take 30 to 50 years or more to grow and form. One careless hiker stomping through it can erase many years of patient development in seconds. If you want to know more about this critical element of sparsely vegetated ecosystems you could look at this site http://science-ed.pnnl.gov/pals/resource/cards/cryptogamic_crust.stm Our naturalists all tied this type of soil to the importance of staying on the trails so as to not interfere any more than you have to with the natural surface. This was new to us and for the rest of the hike we were all looking for patches of this important desert material. And of course we exercised renewed caution in where we were stepping.
Some of our other morning highlights
Ann, our main guide, brought us a bag full of barrel cactus fruits from a plant in her own yard to taste. In nature they look like this.
She had cleaned them up nicely and here one of our group prepares to take a bite. I had a taste too and found them rather sour but not completely unpleasant.
Bird sightings are always a part of these walks. Today we saw a nice Gila Woodpecker on the top of a Saguaro.
After negotiating the Bluff Trail we ended up once again at Sabino Lake. The dam that created the lake was built by the CCC in the 30's, but sedimentation over the years has turned it pretty much into a small pond that is still pretty, but clearly no lake.
Down below the dam the recent rains are continuing to feed a lot of water into the lower part of the creek.