High Water and Low Bugs

The Platte River Prairies got four to five inches of rain last week, filling up the sloughs (old river channels) in many of our floodplain prairies. This will help quite a bit with the lingering drought conditions we’ve been dealing with. It also provided a chance to photograph some of our sedge meadows with standing water, something I’ve not had much opportunity to do over the last couple years.

I wasn’t able to get out on Friday, but arrived at one of our prairies before sunrise on Saturday. I was wearing rain pants, rain jacket, and neoprene boots, anticipating that I’d be wading through and kneeling in shallow water. As it happened, I also laid down several times, which my rain suit wasn’t completely adapted to. It made for a damp ride home, but it was well worth it.

Gently flowing water running through an historic river channel in a floodplain prairie.

I spent most of my time along a single large slough that still had half a foot or more of water in it. The water level had clearly dropped during the previous day and was gently running to the east, where it would eventually meet up with the Platte River. It was a peaceful, beautiful morning, with birds singing and a light breeze rustling the leaves of last year’s prairie plants.

I took some photos of the landscape, complete with moon and colorful clouds, before the sun rose, and noted the calls of the first grasshopper sparrows and eastern meadowlarks I’d heard this year. The vast majority of meadowlarks in the Platte River Prairies are the western species, but I think this site has had a few eastern meadowlarks present each year for at last 30 years now. I wonder if it’s the same multi-generational family through time.

The same slough from a different angle.

Usually, big rain events strands ground-dwelling invertebrates in the vegetation above standing water, waiting for the water to recede. One of this year’s Hubbard Fellows (Kees) had sent me photos from the this site the previous day showing a bunch of pill bugs (aka sow bugs, rolly polies, or woodlice) that had retreated upward. Sure enough, they were still there.

I was a little surprised not to see the scads of ants I’ve seen after other storms. I wonder if that’s because the ground beneath the standing water is usually saturated enough that it prevents ant burrowing. In other words, maybe ants weren’t living in the area that flooded. If the water had spread out to the broader landscape, covering more mesic prairie, maybe it would have stranded more ants? I didn’t see many beetles or other insects either. Pill bugs, though, were very abundant. I saw clusters of up to 50 or more on the same plant.

A pill bug stranded above standing water.
Lots of pill bugs on the same bunch of grass as the sun rose.

I hope you appreciate the above photo because taking it led to the first seepage of water between my rain jacket and rain pants. I’d been doing well propping myself on my elbows and keeping my mid-section out of the water (those planking exercises were paying off!) but for this shot I had to extend a little further into the slough to get the right angle. The things I do for dumb bug photos…

Pill bugs
A moody shot of a single pill bug
A glamour shot of a pill bug in nice light
Another single pill bug on a sedge (probably woolly sedge – Carex pellita)

I came across a few big white scarab beetle larvae floating or stranded in shallow water. Most seemed to be still alive. Going back to my ants-in-saturated-soil hypothesis, I wondered if they’d actually been underground beneath the slough. It seemed unlikely, but what do I know? My guess was that they might have come up to the surface in higher areas when the heavy rains saturated the soil they’d been in. Then they might have been washed into the sloughs from there. Counter hypotheses (or facts) are welcome…

I saw several of these scarab beetle larvae in the slough. This one was still alive, though it didn’t seem happy.

As the sun rose, I took some more landscape photos, including the one below, which was a nearly identical framing as that of the first photo of this post. An hour’s difference in the light, though, makes the photo look pretty different!

This photo was taken an hour after the first photo of this post. The colors and light were really different. Diffuse clouds reduced the sun’s intensity a little, but it was still a lot warmer light than before sunrise.

Most of our wetland and wet prairie sedge species are blooming right now and it was fun to see a lot of them around. Sedge identification can be pretty tricky under the best circumstances, but all the keys I have rely on the sedges being the seed stage. When they’re actively flowering, all I can do is guess based on the location, height and density of the plants, and sometimes the growth form. One the flowering period is over, there’s a window of time in which I can look at features like perigynia, spikelets, stigmas, pistillate scales and other fun botanically-named plant structures that allow me to distinguish between species.

We’re lucky in Nebraska that the Flora of Nebraska has an excellent dichotomous key for sedge identification. Some of the terminology can be a little intimidating at first, but if you’re motivated, I’d encourage you to dive in and give it a try. Once you can start identifying species, you can marvel at the diversity of sedge species in prairies and wetlands! Not surprisingly, in plant communities called “sedge meadows”, sedges make up a pretty important part of the ecosystem…

I won’t even guess at the identify of this sedge at this stage.

This might be a good time for a quick rant. Even if it’s not a good time I’m gonna do it.

You may have heard the phrase “sedges have edges”, or the longer version, “sedges have edges, rushes are round”. These are dumb and nearly useless phrases, in my humble (but strong) opinion. The “edges” part refers to the idea that sedges are supposed to have a triangular stem in cross section. When you roll the stems in your fingers, you can feel the “edges” of that triangle.

The problem is that while all (most?) sedges have leaves that extend out in three directions, not all of them have noticeable triangular stems or edges. Even worse, other wetland graminoids like bulrushes often have very distinct triangular stems with obvious edges. That pretty much spoils the value of the phrases, doesn’t it? Let’s all agree to stop using the “sedges have edges” thing, ok? The fact that it rhymes doesn’t make it accurate.

Thank you for listening.

These are likely Crawe’s sedge (Carex craweii), but that’s only because I know the site pretty well and thel location, height and density match up with what I’d expect for that species.

It’ll be interesting to see if last week’s rain is enough to pull the Platte River Prairies out of the “moderate drought” category on the Drought Monitor website. Regardless, the precipitation was probably enough to significantly change the competitive balance in our plant communities for at least the next month or two.

We’re constantly applying fire, grazing, haying, rest, and other treatments to the prairies, each of which can favor some plant species while suppressing others – depending upon treatment timing, intensity, duration, and other variables. Weather patterns, though, also play a very significant role in determining which plants will find favorable conditions to grow, bloom, and thrive each year. Our prairies look very different in dry years than in wet years.

Of course, wet and dry conditions also affect animal and other communities as well. As we’re seeing right now, rapid changes in water levels and soil moisture can affect species like pill bugs, ground beetles, ants, and many others. At the same time, those new conditions will be really attractive to all the shorebirds and other water birds migrating through, as well as those looking for local nesting sites.

Looking beyond short-term changes, though, if this turns out to be a fairly wet year, it’ll have positive and negative consequences for lots of animals. While lush vegetation growth will be great for many, higher rates of fungal infections and other pathogens can be problematic as well. Pollinators and other invertebrates that specialize on plants that thrive in wet years will celebrate, but those that focus on plants more adapted to dry conditions won’t find as many opportunities.

Either way, diverse prairies are well-adapted to variability in weather and other factors. As managers, our job is to facilitate the species diversity that maintains that adaptability. And, of course, we can admire and celebrate the ways in which prairies flex and modify themselves to meet whatever comes.

Photos of the Week – April 23, 2024

Over the weekend, my wife, Kim, and I were at Wilson Lake in Kansas. Longtime readers know that Kim runs ultramarathons and that I usually accompany her when she goes to races or long training runs. This weekend, she was signed up for a “backyard ultra” in which participants run an approximately four mile loop once an hour for as many hours as they can. They have to be back at the starting line at the top of each hour to avoid being disqualified. Sounds fun, huh?

Kim was mostly using the race as training for another race coming up next month, so she only planned to run 8 loops. The serious racers were each planning to run until they were the last one left. The eventual winner ran through the day, the night, and much of the next day, ending at something like 30 laps and 125 miles. Kim was feeling good after her first eight loops and ended up doing an extra one to end up at 37.5 miles.

Here’s Kim toward the end of her 37.5 mile run. Yes, that’s miles, not kilometers.

My role in all this was to be at the starting point a few minutes before each hour to help refill Kim’s water and hand her food, dry clothes, or whatever else she needed before she headed back onto the trail. It was pretty exhausting work, but my training got me through it. I only missed one time and that was because our car went crazy and locked me inside while it blared the theft warning horn and lights. I hadn’t adequately trained for that, apparently.

During one of her brief stops between laps, Kim handed me a plant with yellow flowers and said, “I think this is a Corydalis, right?”

This is just one of many reasons I love my wife. She enjoys the challenge of long trail runs, but she’s also there because of what she can see along those trails. She’s very good at recognizing and appreciating what she sees. It’s nice that we can share these experiences. It’s especially nice that she’s happy to handle the running part by herself.

Yellow Corydalis (Corydalis lutea) – I think.

Kim was, of course, correct about the Corydalis. I wandered out and found a few plants to photograph during her next lap. Then I looked online to see what species it might be. I’m pretty sure it’s Corydalis lutea, which is a non-native, but apparently fairly innocuous wildflower found in that part of Kansas. It’s very pretty.

The Corydalis plants were small, but the flowers were really attractive.

I’d been hoping to do a lot of photography during the race, even though I knew I’d be on a relatively short tether because of my hourly responsibilities at the starting line. This is a site Kim runs at fairly frequently, so I’m starting to become familiar with where certain species hang out. During a few periods when the overcast skies brightened a little, I grabbed my camera gear and wandered through the nearby rocky prairie, checking out some likely spots.

The temperatures were too cool for most creatures, including the ants at my favorite ant mound. I didn’t see any of the eastern collared lizards I photographed last summer, either. I did, however, find a couple new-to-me plant species. That’s assuming my cursory plant identification was accurate.

I’m familiar with western wallflower (Erysimum capitatum) from lots western Nebraska sites, but it was nice to see it blooming along the trail.
Based on how fuzzy these leaves are and the rocky substrate beneath it, I think this is probably Tharp’s spiderwort (Tradescantia tharpii) but I’m not familiar with the species and could be wrong. Maybe it’s just a really hairy example of Tradescantia bracteata. Either way, it was really attractive.
I’m pretty sure this is Buckley’s penstemon (Penstemon buckleyii), which is another new species for me. It was growing in very rocky/sandy terrain.
More penstemon.
Here’s a close-up of the penstemon flowers. While the leaves of the plant look similar to shell-leaf penstemon (Penstemon grandiflorus), the flowers are very different.

Prairie shrubs were in bloom around Wilson Lake, including wild plum, currant, and skunkbush sumac. I didn’t end up close enough to the first two to get photos of them, but I managed to photograph the skunkbush sumac. As I was finishing that photo, I saw a little butterfly out of the corner of my eye and was able to track down a common checkered skipper that looked freshly emerged.

The little butterfly posed on the trail for a short time and let me get some close-up portraits of it. This species is common in both Kansas and Nebraska, but is apparently found from southern Canada all the way down through South America. This one looked like it was trying to warm up by absorbing sunlight with its widespread wings, but there wasn’t much light or heat to absorb. I got a couple quick shots and then left it alone.

A common checkered skipper trying to capture some radiant heat on a cool, cloudy day.
Common checkered skipper – side view.

I’ve got just under a month to get in shape for Kim’s next race, which will be a much longer one. I’ll probably do some squats and knee bends to make sure I can get down to the ground for insect and wildflower photos. I need to get my camera batteries charged up and lenses cleaned. Apparently, I should also do some reading about the anti-theft features of our car so I can avoid a repeat of that whole fiasco.

Oh, and Kim will do a lot more training runs. This is a team effort, after all.