Friday, June 29, 2018

Canyon life, past and present

Two families came out for our June hike. In fact, a few were the youngest hikers we've had this year. All ages, shapes and sizes can hike the Madrone Canyon Trail!

At the beginning of each hike, Jean explains the history of the canyon: "Over the past hundreds of millions of years, this area has been alternately under and above the sea. Many different layers of sediments were laid down, creating different kinds of sedimentary rock. Ocean and salt marsh organisms created hard layers of sedimentary limestone and fossils." And fossils, like this bivalve mollusk, have been found in the canyon, the former shells of an ancient sea creature.
This hiker found a bivalve mollusk fossil which he put back where he found it, in keeping with good trail etiquette.

Here, a different kind of shell, the eggshell of a bird, possibly the Bewick's wren (pronounced Buick) often seen in our canyon. Chicks have an "egg tooth" used to exit the shell, making a nice clean opening from which to emerge. That's how we know this bird egg didn't fall from the nest.
Happy hiker found a bird's eggshell!
Oftentimes, hikers will find bones of animals, like these vertebrae, pieces of a mammal spine. Can you guess what all three of the hikers' finds have in common: seashell fossil, eggshell, and bones? Hint: All three contain this mineral. You'll find the answer at the end!

Finally, flowers! Berlandier's sundrops, Square-bud primrose and Sundrops are all common names for Calylophus berlandieri

Here's another primrose, where you can see the bud, flower, leaves and fruit (seed pod) of the Bigfruit evening-primrose, Missouri evening-primrose or Fluttermill, all common names for Oenothera macrocarpa.  

Flower buds were on the stalks of Devil's shoestring or Ribbon grass, both common names for Nolina lindheimeriana. 


The common name of this plant is Lady Bird's centaury, (Centaurium texense).  It is in the Gentian family of plants and similar to another centaury often seen on our limestone canyon walls called Mountain pink (Centaurium beyrichii).


The answer to the above question is: calcium carbonate. Congratulations, if you guessed correctly!

Due to the July 4th holiday weekend, we will not lead a hike on the first Saturday of July. The same goes for August, no hike planned, just because it's so hot! But you're always welcomed to hike the canyon on your own.  Jean and I will be back for a hike on Saturday, September 1, 2018 at 10 am.

Keep cool!
Paula