Bouncing Back

large-flowered leafcup

Interrupting my series on astery things and butterflies for a quick update on the Potomac Gorge, where I went this past Tuesday. After all the flooding, many plants are coming back. They aren’t as tall as they normally would be at this time of year, and some of them are just starting to bloom or bud up, a month or two late.

On the riverbanks, large-flowered leafcup (Smallanthus uvedalia) and cut-leaved coneflower (Rudbeckia laciniata) are blooming. A few New York ironweed (Vernonia noveboracensis) are also growing, looking short but with lots of buds.

cut-leaved coneflower

Right by the water’s edge, a few halberd-leaved rosemallow (Hibiscus laevis) are up, at about one-third of their mature height. I found one just starting to form buds; in other years, these plants started blooming in mid July.

buttonbush

In one place I saw an exceptionally short and shrubby-looking buttonbush (Cephalanthus occidentalis) with a few flower heads just formed, one with buds that will open any day now. In this area they usually start blooming in late June or early July.

woodland sunflower

Inland where there wasn’t any flooding, some of the typical mid-to-late summer bloomers are starting: two species of thoroughworts (Eupatorium) and goldenrods (Solidago) with buds just about to burst.

Starry campion (Silene stellata) and woodland sunflower (Helianthus divaricatus) are in full bloom. There were just a few blooms left on a stand of St. Andrew’s cross (Hypericum hypericoides).

cranefly orchid

And much to my delight, cranefly orchid (Tipularia discolor) is out.

Devastated

the hotspot, 30 July 2015

“Please rain,” I wrote earlier this year. We got rain, alright. This past May was one of the wettest on record. The Capital Weather Gang reported more than 10 inches of rain in a 23 day period. There was a lot of flooding in the Potomac basin.

Not that I was around to witness it; I was traveling. But the clues are still there: deposits of debris, dried mud on the upslope side of the Billy Goat C trail, muddy tree leaves six feet off the ground, that sort of thing. I saw them this morning when I went out to have a look at my favorite bedrock terrace, which I call the hotspot.

the hotspot pond, 10 June 2015; note how lush, with arrowhead in the water

My usual path to it, across a narrow channel, was still underwater, so I went to another low spot and was able to get across via an islet.

The islet was almost empty: only a few plants, maybe a foot tall coming up through the freshly deposited dirt, no more than one plant per square meter. Big piles of woody material, downed trees, shrubs, and vines on the upstream side of boulders and large trees. Lumber. Plastic and glass bottles. A child’s flip-flop shoe.

jimsonweed on the islet, 10 July 2014

I’ve never gone through that area because by this time of year, it’s waist-high or taller in jimson weed.

the hotspot, 30 June 2016, with a bit of the pond in the foreground

The hotspot was almost empty, too. A few nodding onion on the higher rocks. Racemose goldenrod starting to grow. One small clump of big bluestem grass blooming. Remnants of trumpet creeper and poison ivy. A few scraggly shrubs that might be buttonbush. Very little else.

One of the delights of the hotspot is a pond that’s tucked into the rocks, well above the river. The pond supports aquatic plants, and wetland obligates grow next to it. This year, that little pond held more water than I’ve ever seen in it, but nothing green. The rocky edges were crusted in dried mud. No plants.

the hotspot, 18 July 2017; note how low the water in the pond is, but the area is still lush; zoom in to see flowers on buttonbush and milkweed

Last July in that area I saw flowers on buttonbush, wild potato vine, swamp milkweed, Carolina horsenettle, water willow, thin-leaved sunflower, swamp candles, common arrowhead, fogfruit, and nodding onion. Seedpods on wild blue indigo, and buds on Culver’s root. Halberd-leaved rose mallow taller than me and budding up. Same with joe-pye weed. And cardinal flower. And leafcup and cut-leaved coneflower. Honeyvine climbing over everything, not yet blooming. There was a middle-height forb I identified later as Ludwigia decurrens, the first report of this species in Montgomery County.

This year, on the riverbanks near the hotspot the rosemallows are starting to regrow. Leafcup, coneflower, and sunflower are as well, but they’re only about a foot tall. There’s some water willow in the river. I couldn’t find a trace of any of the other plants: no joe-pye weed or wild blue indigo or Culver’s root or cardinal flower. No honeyvine.

I’m devastated. I won’t get to see those nifty flowers this year.

the hotspot and pond, 3 July 2018

The hotspot, however, was not devastated. This sort of flooding is part of the natural rhythm of the Potomac; the river’s occasional scouring of the bedrock terraces is one of the factors that allows unusual plants, and unusual plant communities, to thrive there. I have no doubt that all the species I mentioned above will be back next year (unless it floods again), in all their glory. And maybe the river will have brought something new.

check the archives for July, 2017, for pictures of plants growing in the hotspot: Golden Glow, Bewitched by Buttonbush, Common Arrowhead, and Ribbet

Compressed (part 3)

And here are a few more early spring bloomers to watch for in the Potomac Gorge.

Not as common as some of the flowers in yesterday’s post, but still easily found in rocky areas, are early saxifrage (Micranthes virginiensis, formerly Saxifraga virginiensis), which are the white flowers on the right in this photo, and smooth rockcress (Boechera laevigata, formerly Arabis laevigata), which is the plant in bud on the left.

Growing right on top of boulders, the incomparably wispy and delicate lyre-leaved rockcress (Arabidopsis lyrata, formerly Arabis lyrata) are in full bloom already, but they have a long bloom period.
Also growing right on rocks, though in more open, sunny areas, is moss phlox (Phlox subulata). It, too, has a long bloom period.

Its cousin wild blue phlox (Phlox divaricata) is just starting to open in the dappled shade of the woods.

In a few upland areas, rue anemone (Thalictrum thalictroides) are just starting.

 

 

Don’t forget to look up! Spicebush (Lindera benzoin) is in full bloom.

 

 

 

 

Another yellow-flowering woody plant is leatherwood (Dirca palustris), but it’s uncommon. If you find a stand please post a comment!

 

 

And in deep shade on the forest floor, there are toadshades (Trillium sessile), delightful even before they flower.

 

 

Compressed

Friday afternoon I met two entomologists on the trail. “Everything’s all stacked up,” they said, meaning the bugs are all coming out at the same time. It’s pretty much what I’d been thinking about the wildflowers, because they’re doing the same thing: opening all at once, rushing into spring as soon as Persephone flings open the doors.

Of course it got cold again today, but yesterday, once the sun came out and temperatures rose into the 60s, the show was extraordinary. I expect it will be again tomorrow, and any other warm, sunshiny day in the coming week.

This was in the Potomac Gorge, of course. I have no idea how long the flowering will last. Get out there soon. Details and pictures tomorrow or Monday, as soon as I have time.

Nativity and Granularity

I’m fascinated by words, their sounds, their rhythms, their meanings. By semantics. Mostly I try not to be pedantic about words, but when the subject is “native” plants, I have to be.

It’s a word and concept that comes up all the time for us botanerds. Like asking if the newborn baby is a girl or a boy, nativity is where our understanding and appreciation of a plant starts.

But why? Why do we care, and what does it really mean, anyway?

Merriam-Webster defines “native” as “living or growing naturally in a particular region”. The USDA offers a more specific definition:

A plant that is a part of the balance of nature that has developed over hundreds or thousands of years in a particular region or ecosystem. Note: The word native should always be used with a geographic qualifier (that is, native to New England [for example]). Only plants found in this country before European settlement are considered to be native to the United States.*1  [emphasis mine]

In an online forum the topic recently came up, with respect to wood poppy (Stylophorum diphyllum, pictured above). Have a look at the USDA PLANTS Database distribution map for it:

The map implies that wood poppy is native to Maryland. Now have a look at the county-level map (same page, zoomed in):

This map shows wood poppy present somewhere in the state of Maryland (the light green color means that there are no county-level records). Note that other than in Maryland, there are only two locations east of the Appalachians where wood poppy is present: southeastern Pennsylvania and the District of Columbia. Considering the rest of the distribution, it doesn’t really make sense that there are “naturally occurring” populations of this species outside the mid-west.

Various sources I’ve checked agree that wood poppy is not native to Maryland. According to Alan Weakley, wood poppy is found in

Moist forests over calcareous rocks (such as limestone). Mar-Jun. S. QU, w. PA, s. MI, and WI, south to sw. VA, e. TN, nw. GA, sc. TN, and AR; introduced elsewhere from horticultural use. [= C, F, FNA, G, K, Mo, Pa, S, Va, W, WV] *2    [emphasis mine]

This is not to say that the USDA PLANTS Database is untrustworthy. It’s an excellent source of good information. My point here is that without the right qualifier, it’s useless to ask if a plant is native. In this example, it’s correct to say that S. diphyllum is native to North America, and it’s correct to say that it’s native to the lower 48 states, but neither of these statements implies that the species is native in every wild place it’s found.

Since wood poppy is not native to Maryland, but is found growing wild here, we need a word other than “native” to describe it. “Alien” would be technically correct but that word is loaded with negative connotations. The correct term is naturalized.

Getting back to that idea of geographic qualifiers, it’s possible to go a little crazy when you’re trying to decide if something is native. Consider Baptisia australis (wild blue indigo), which has a scattered distribution in the eastern US. In Maryland it is known in only a few locations along the Potomac River, including the Potomac Gorge. So if I were being utterly ecologically correct, I wouldn’t grow it in my garden, because my garden isn’t in the Gorge; it’s about a quarter mile away at a different altitude and on a different underlying rock formation.

But that is a ridiculous level of granularity. If I’m trying to build a showcase garden of Maryland native wildflowers, should I exclude these two species because the one is naturalized and the other grows only in very specific locations?

The answer to that question consider the maxim “first, do no harm.” More on that next time.


*1Natural Resources Conservation Service
*2Flora of the Southern and Mid-Atlantic States, page 465

maps from USDA, NRCS. 2018. The PLANTS Database (http://plants.usda.gov, 19 February 2018). National Plant Data Team, Greensboro, NC 27401-4901 USA.