It was interesting to see the history of how the desert was formed over millions and millions of years. We exited that exhibit and walked out to the veranda overlooking the desert trail below that you can tour as part of the museum education. We struck up a conversation with a volunteer, Nathaniel, who educated us on the Saguaro Cactus. The cactus only bloom in the first part of May each year where birds eat the seeds and then deposit there droppings usually near shaded areas where the seeds can get moisture and begin to grow. Only one in a million seeds that is deposited ever begin to grow into a cactus and only one in a billion seeds then grow into an adult Saguaro. So when you look out over the vast area that the saguaro cactus grow it is mind boggling to think that it took billions and billions and billions of seeds to grow these cactus.
Frost damage to the Saguaro
Severe frost damage to a Saguaro
Nathaniel explained that when you see a narrow band around the trunk or down turned arms of a older Saguaro it was caused by frost or freezing that didn't kill it. He also explained that adult Saguaros don't grow arms until they are over 100 years old. The number of arms is individual to each Saguaro. The Saguaro also has a very extensive root system. The roots only grow down about 18 - 20 inches however they grow out away from the base the same distance as the height of the Saguaro. So if the cactus is 20 feet tall then the roots will extend out 20 feet from the base. This make for a very strong root system to support the weight of the massive trunk. Some of the Saguaros have holes in their trunks made by the Helio Woodpecker. The woodpecker uses their strong beak to break through the cactus surface and hollow out an area to lay eggs and raise their young. They only use this opening once however it is used by other birds like owls. As we walked along the trail through the outdoor museum I happened to see a Helio Woodpecker hollowing out a hole for a nest.
Just happened to get him with his head looking out.
We also saw a prairie dog exhibit. The prairie dogs are very curious and posed for pictures.
By that time it was getting pretty hot out and it was after noon so we headed back to the rig to get out of the heat and rest up for an evening stroll in the desert. We also made plans for our activity today. Visiting Sabino Canyon and riding the tram. More in the next post after I get the photos downloaded. I also have been nursing a slow leak in my right rear 5th wheel tire so I got a call into the extended warranty company with my tire and wheel protection and I contacted a local RV repair service. I have an appointment on Saturday when we leave for our trip to Gold Canyon and our winter destination. I can't see where the problem is but it's getting checked out and fixed. Repair or replacement. Tomorrow we get some really hiking done at Saguaro Nat'l Park. We need the exercise. :-)