The Last Generation – Late Summer Wildflowers

I’m torn between 2 posts today- one that covers some of the hydrology, botany and geology of Sunday’s ride up Diamond Fork, and a catch-up post on Wasatch wildflowers of late August. (I’m traveling for work this week, and probably won’t have time for more than a couple posts.) Though the Diamond Fork post is top of mind right now, I’m going with the Wildflower post first, for 2 reasons:

1) A lot has changed since the last time we checked out Wasatch wildflowers, and we’re approaching the end of summer. The wildflowers blooming now are pretty close to the “last generation” of the season, and I should blog about them just a bit before summer wraps up entirely.

2) I’m afraid that if I do the Diamond Fork post right now, I will lapse into a rant about a neighbor*. So I’m giving myself a day or two to cool down.**

*It may not seem possible that a Diamond Fork ride and one of my neighbors are connected, but oddly, they sort of are.

** Of course it is entirely possible that I may do the Diamond Fork post Tuesday or Wednesday or Thursday and still lapse into a rant about the neighbor, but I’m determined to at least give myself a cool-down period.

Way back in the Spring I blogged about staggered blooms, and that same staggering has been occurring all summer long. We’ve seen little snapshots of it as I’ve blogged about different flowers over the past 4 months. But between Maine and Montana, I didn’t do much riding in the Wasatch in August until this past week. And when I came home and started riding the “home” trails, everything was different.

Tangent: My first full ride back was actually last Saturday, when Hunky Neighbor and I did a ride I now call Super-PBX (pic right). Someday when I have nothing else to blog about maybe I’ll do a map and write up explicit directions, but for now suffice it to say that Super-PBX includes all the best parts of the Pinebrook trail network, plus the Northernmost stretch of Mid-Mountain (between Pinebrook & Rob’s) out & back, plus a thrilling return via Finesse trail (both upper and lower.)

It’s about 19 miles, at least 60 switchbacks, much of the best singletrack along the Wasatch Front, and the trailhead is a 15-20 minute drive from the East side of SLC. And- no, I am not shitting you- you hardly ever see anyone on the trails. It’s just awesome. Every flower mentioned in this post (except Snakeweed) is along Super-PBX right now.

Where We Left Off

The last flower I blogged about in Montana was Goldenrod, and it is super-common right now in the Wasatch below ~7,500 feet. Although I blogged about it already, there are 2 more things I should mention about Goldenrod before moving forward. The first- which I can’t believe I skipped over- is that it belongs to Asteraceae, the Sunflower family. That’s right, those unassuming little yellow flower-clumps are composites, and closely related to things like Dandelions, Balsamroots and of course, Sunflowers. This may seem trivial, but it’s not, and we’ll come back to it later in the post.

No, You Are Not Allergic To Goldenrod

The second thing is that if you ask people what they know about Goldenrod- particular in the Eastern US- they’ll tell you it causes hay fever. It doesn’t. Goldenrod pollen is big, heavy, and poorly dispersed by wind; Goldenrods are pollinated overwhelmingly by insects. Ragweed (genus – Ambrosia, many different species) which blooms at the same time has light, wind-borne pollen, and is a common and vigorous allergen. Because Goldenrod blooms so visibly, in many of the same places, at the same time, it often is unfairly given the bad rap due Ragweed.

Goldenrod flowers are yellow of course, which brings up the whole topic of why so many late-blooming August wildflowers are yellow. Yellow flowers bloom throughout the season, from Glacier Lilies to Mules Ears, but it seems like so many of the flowers in August are yellow. I’ll come back to this later in the post as well.

*Yes, I know I’ve now set up 2 teasers, but the fact is that this post is a bit dry, lacking the drama say, of the Awesome-Wife-Bear post, and I feel the need to “tart” it up a bit with a little suspense…

Speaking of yellow flowers, this next one is almost done blooming, but you can still find it pockets up around the 8,000 foot level, and because it was so common throughout August (and big and easy to ID) I feel the need to include it. It’s Arrowleaf Groundsel, Senecio triangularis, and though its height, form and leaves are all different, if you check out the flowers you’ll see they’re almost a dead ringer for those of our old friend Singlestem Groundsel, which so thoroughly dominated the high rangelands and Aspen meadows way back in June. What’s interesting about these 2 closely-related flowers is that they sort of act as temporal “book-ends” of the mid-elevation Wasatch. The summer bloom around Park City both opens and closes with a Groundsel. Like its Singlestem cousin, S. triangularis is another member of the Sunflower family. Most, as I said, are post-bloom now, and look more like the pic left.

Some Brushy Stuff

Another yellow flower you see blooming everywhere right now- especially by roadsides lower down – is Rabbitbrush, a super-common shrub in Utah and throughout the Intermountain West. It’s so ubiquitous that it’s in that I’m-Embarrassed-I-Haven’t-Blogged-About-It-Yet category. There are a bunch of different Rabbitbrush species around, and they can be tough to tell apart. Rubber Rabbitbrush, Ericameria nauseosus, (which in turn is broken out into something like 20 subspecies) is probably the most common at lower elevations, but up around Jeremy and Pinebrook (6,500 ft) I’m pretty sure the most common right now is Green Rabbitbrush, Chrysanthomnus* viscidiflorus.

* Confusingly (for the amateur- that would be me) Rabbitbrushes have been recently broken into 2 genera. Formerly they were all lumped together in Chrysanthomnus.

Rabbitbrush has crowded little clusters of tiny yellow flowers, and from a distance when blooming it looks like maybe some member of the Parsley or Mustard families. But it’s actually a member of-no kidding- the Sunflower family. When you get up close, each of those tiny little yellow blossoms is a composite of 5 or 6 disk flowers (and no ray flowers.) Rabbitbrush is a late bloomer high and low, and it’ll brighten trails and roads around Utah for weeks (months down low) to come.

Botany-Tangent: Something that stymied me for a long time was distinguishing Rabbitbrush from Broom Snakeweed, Gutuerrezia sarothrae. Snakeweed, though native, is one of the most common weeds on Western rangelands and can be toxic to livestock. It has a similar form as Rabbitbrush, blooms around the same time, and also sport clumps of little yellow flower. The easiest way to distinguish the 2 is usually size- Snakeweed is only ankle-to-shin high, but Green Rabbitbrush often occurs at that smaller height as well, making it easy to confuse the 2.

Up close though, the flowers are easy to tell apart. Snakeweed blossoms have little “petals”- actually ray flowers- while Rabbitbrush flowers are disk-only composites. And yes, Snakeweed, another late-bloomer, is yet another member of the Sunflower family. Snakeweed stems, BTW, are thinner and more brittle-looking than those of Rabbitbrush, which is easier to see if you come across the 2 side-by-side. (pic left of the 2 together up Second Water trail in Diamond Fork. Sorry for the crappy quality- group ride, quick snapshot, that’s how it goes…)

Most Common Wasatch Flower Right Now

But the most common yellow flower – and simply the most common flower period- in the Wasatch right now is this guy, Showy Goldeneye, Heliomeris multifora (pic right). It’s yet another member of the Sunflower family, and its name comes from the slightly darker shade of the disk flowers, creating the “eye” effect.

Showy Goldeneye was historically placed in another genus, Viguiera, the Goldeneyes, all native to the Western Hemisphere. But in recent years genetic research has shown Viguiera to be paraphyletic*, meaning not a group which includes all the descendants of a common ancestor. This research led to the creation of several new genera, including Heliomeris, which includes just 4 species of Goldeneye, all native to Western North America and which appear to share a common ancestor, morphology (leaves opposite lower on stem, but sometimes alternate higher up) and haploid chromosome number (n=8). This kind of re-classification is going on all the time right now in our biology, and it highlights why now is such an amazing time to be alive: genetic research is revealing so much and forcing taxonomists to revisit many long-held assumptions about how living things are related to one other, in the process revealing thousands of hidden little stories about the origin and evolution of so many species.

Yellow is the dominant wildflower color in late August, but it’s not the only one. Here are a couple of other common examples you’ll see in the Wasatch right now.

Negative Daisies Revisited

We’ve talked previously about Negative Daisies, the most common of which is Showy Fleabane or Showy Aster, Erigeron speciosus (pic right, alongside Showy Goldeneye). It’s- if anything- far more common now than when I blogged about it a month ago, tucked into nooks and crannies in practically every meadow above 6,500 feet. But there are lots of other Negative Daisies blooming now as well. One example is Thick-Stemmed Aster, Eurybia multifora (pic below, left). Though similar in form and color to so many other Negative Daisies, the “petals”- actually ray flowers- are distinctly “skinnier”, than those of Showy Fleabane, for example, with a visible gap between each, and typically darker in tone, ranging to a deep purple in color.

Thick-Stemmed Aster used to be classified as- and is still listed in many (most?) flower guides as Aster integrefolius, but recent genetic research has reclassified many Asters into a number of new genera- wait a minute- didn’t I just tell this story? Yes, it’s the same story as Showy Goldeneye, and I am telling you, it is happening all the time. The mysteries being revealed about living things through such research are arguably some of the most profound discoveries in our lifetime- in terms of knowledge gained they’re arguably more significant than the moon landings*- and yet most people are largely unaware of this explosion of new knowledge.

*Please don’t leave a comment saying you weren’t alive during the moon landings; you’ll make me feel old.

Side Note: The research related to Asters is worth a post of its own. “Aster” is one of the more confusing words in botany; it’s a specific genus, but is also used as a name for many flowers which never were considered part of that genus (like Engelmann Aster, which I blogged about in late July), as well as flowers like Thick-Stemmed Aster, that used to be considered part of the genus, but aren’t anymore. Genetic research has recently shown the genus Aster to be polyphyletic, leading to the creation of Eurybia and numerous other new genera that better reflect these plants’ true phylogenetic relationships to one another. Aster researcher Jon Semple of the University of Waterloo has made the case over the past decade-plus that there are no native North American Asters, and that all such plants should be reclassified into different/new genera.

Eurybia includes just 23 species, all native to North America, which appear to share a common ancestor, form and haploid chromosome number (n=9).

One More Daisy

Lest we think all blooming composites right now are yellow or lavender, I’ll mention one more, the Vernal Daisy, Erigeron pumilus (pic left). Though not as common as the others I’ve mentioned, I like this yellow/white daisy because it’s one of the most visually similar to Bellis perennis, the European Common Daisy. It’s also similar in color and form to Engelmann Aster, but the ray flowers seem more “fleshed-out” without the visible gaps in between them, and the “eye” of disk flowers seems fuller, with a distinctive close-up profile that becomes quite recognizable once you’ve ID’d it a few times.

These last 3 flowers, BTW, may not be yellow, but they’re all members of the Sunflower family. And that brings me all the way back to the 2 oddities I referenced at the beginning of the post- that so many August flowers are yellow, and that the overwhelming majority belong to the Sunflower family.

The Mysteraceae of Asteraceae

The yellow part actually doesn’t seem to be much of a mystery- it’s the most common color of Asteraceae flowers, at least in this part of the world, and since virtually everything blooming is a member of that family, it makes sense that a lot of them would be yellow. But the second question is a more of a head-scratcher for me, and I’ll start by flipping it around: Why are there no more non-composite flowers blooming now? Think about it. Over the season we’ve seen dozens and dozens of non-composite flowers- Lilies, Sweetpeas, Larkspurs, Geraniums, Bluebells, Fritillaries, Wild Roses, Clematis, Lupines*. But except for some lingering, scattered pockets, they’re all done blooming. Practically everything blooming now is a composite, and more specifically, a Sunflower-family-composite. If aliens landed in Utah right now, they might well assume that all flowers here were Asteraceae. Why is that? What is it about the Sunflower family that makes it dominate the bloom so thoroughly in late summer?

*Actually, a number of Lupines are still blooming in the Wasatch, but most are post-bloom and on their way to peapod-dom.

Side Note: Western Coneflower, another Sunflower family member about which I’ve blogged previously is also blooming like crazy now (pic right) around 8,000 feet.

Half-Cocked Conjectural Part Of Post

I don’t know the answer. For all I know there’s a super-obvious, well-established answer which I just haven’t been able to find in a book or coax out of a google search. But I’ll hazard a guess. Asteraceae all produce achenes*, which are small and dry. Although they’re technically fruits, they’re not much more substantial than seeds with a tough coating. Two things occur to me about achenes: First, compared to a real “fruit”, like a berry or a hip or such, they don’t involve a lot of mass and structure, which means they probably don’t take as long to grow. That should mean that you can start growing them later in the season and still have time to grow them to “maturity” before cold weather sets in. Which in turn might mean that you could flower/breed later in the summer, when there’s not so much competition for pollinators (pic right. I love how the bumblebee came out in this shot. click on it, isn’t it cool?) from all the plants that grow berries and cherries and hips and such, who all had to flower/breed way earlier in the season so as to have enough time to grow their more substantial fruits to maturity.

* I explained achenes in this post.

Second, achenes hold hardly any moisture, compared to berries, cherries and such. And that probably means that an achene-producing plant can develop its “fruit” under drier conditions, such as the Wasatch in late August.

If you compare the Sunflower family to arguably the 2^nd-best represented flower family in this blog- the Rose family, Rosaceae- the hunch makes sense. There’s no Rose family member blooming now in the Wasatch; the Wild Roses, Serviceberries, Chokecherries and Ninebarks finished flowering long ago. For the last month or two they’ve been busy growing fruits. (pic left = Serviceberry loaded with berries)

Of course, like all my guesses/hunches, this could way be way, totally wrong*. Don’t use this post for your science report.

*And here’s one possible exception: Mountain Mahogany, a Rose family plant that produces achenes, but still blooms in early summer.

The drying understory, accented by the yellow and lavender blooms of late summer, give the Aspen forests a lazy, languid feel, as if they hadn’t a care in the world, and the summer could stretch on forever- a sense and theme I hope to return to in the next post. But of course nothing could be further from the truth. Change is just around the corner.