And now on to the boring stuff. Here are my notes of mesa botany after several weeks of observation.
The 2 most abundant species found on the mesa are the scorpionweed aka The Wild Heliotrope aka the scalloped phacelia, which is a bright purple flower, and the spectacle-pod (dithyrea wislizenii) which has a white flower. Both of these plants are found all over the place and in great abundance. They have peaked up on the mesa but are still doing quite well on the slope from my back yard to the top.
The next most abundant is probably the scarlet gaura (gaura coccinea). I thought this one would be hard to identify, but actually I figured it out right away. It's a member of the evening primrose family. At first I just noticed it here and there, but lately it seems to be everywhere. There is a comment in one of the guidebooks that says that the flower tends to get deeper red as the day goes on. I don't know about diurnal color changes, but I have noticed that patches of the plant are definitely a richer red every day that I walk by.
Milkvetch is found fairly commonly on the mesa. The freckled milkvetch (astragalus lentiginosus) is easily recognized by the big seed pod that it produces. It has a purple flower. I noticed that there was a plant very similar to it that was found in much less abundance. It too had purple flowers quite similar to it. I was fortunate to find a place where the 2 are growing side by side. The other plant is also a milkvetch, but its the crescent milkvetch (astragalus amphioxys) I was happy to be able to recognize differences in what appear to be the same flowers.
In certain areas there are large patches of phlox. These are beautiful purple flowers that can form almost carpets of color. There are many species of phlox, and the best I can come up with is that this is Santa Fe phlox (phlox nana).
One thing I have also noticed is that the populations of wildflowers changes from road to road. Species that I find in one place are absent just a few hundred yards away. I think I made this observation last year after the monsoon rains caused a burst in flowers. Some colored varieties were found in some places but not others. Along one road I found abundant specimens of slender blanketflower (gaillardia pinnatifida) but elsewhere there might be one or 2 scattered about. Lately I have noticed more and more desert blazing star (mentzelia pumila). There are some nice patches along the trail leading up to the top of the mesa. It really is a very pretty yellow flower (pic posted in an earlier post).
And then there have been the flowers where I only find a couple of specimens. The most beautiful flower I have found I have identified is dune primrose (oenothera deltoides) which I have a low confidence in being correct. I have seen these plants before when living in Yuma. They're called "birdcage primrose" because when the plant dries out, it resembles a little cage. I know that this is a low-elevation plant and am not sure if it would be found at 5000+ ft. The flower looks incredibly similar to what I have found in books, so perhaps its just a different species of primrose.
The other day I also identified a different yellow flower as threadleaf groundsel (senecio longilobus). I only found one specimen right at the top of the mesa. The guide says it can bloom at any time of the year but prefers Fall. Maybe that's why I haven't found very many. There was also a patch of intensely yellow flowers along the path up to the mesa. I identified those as paperflowers (psilostrophe cooperi). Just the other day I noticed a "weed" in my backyard which I also just started to find up on the mesa. It has a nice thorny stem which offsets the beauty of the little purple flower. That is silver-leaf nightshade (solanum eleagnifolium. Just starting to bloom are the globe mallows (sphaeralcea coccinea. I expect a LOT of them to be blooming in the near future.
Hidden among some of the spectacle pods in back of my wall I picked out a different white flower. It keyed out as snowball/sweet sand verbena (abronia elliptica)
It's not very pretty, but the wild rhubarb (rumex hynenosepalus) is also blooming with a stalk of pinkish flowers.
The other day I also noticed the first flowering cactus of the year. It's a really lovely cactus! If development threatens it, I may just have to go out there and try to rescue it.
I know I'm missing a few other plants. I need to keep better notes. But there you have it! My summary of plants/flowers found on the mesa for mid-May. I hope I didn't bore you to death.