Prairie Referees?

As grassland stewards, our greatest challenge is to maintain the ecological resilience of prairies so they can adapt to and survive a changing world.  That resilience relies heavily upon biological diversity because high numbers of species helps ensure that important roles are filled, no matter what stressors are affecting the prairie.

Unfortunately, managing land for biological diversity is hard.  Of course it is – the natural world is incredibly complex and dynamic.  None of us has the capacity to become familiar with all the species that live at a single site, let alone how they interact with each other.  How can we be expected to make land management decisions that take care of the needs of all those species and their interconnected communities?

Gjerloff Prairie is a diverse loess hills prairie along the Platte River in Hamilton County, Nebraska. Owned and managed by Prairie Plains Resource Institute, it thrives under a varied management regime that includes both fire and grazing.

For what it’s worth, here’s how I look at it:  All the species in a prairie are competing with others for space and resources.  Our job is to manage the game such that ensures nobody always wins and nobody always loses.  If we can do that, all those species should be able to persist and keep contributing to the resilience of the prairie.

When my kids were 7 or 8 years old, they started playing soccer in our town’s recreational program and I volunteered to be a coach.  At that age level, coaches also acted as referees during games, chasing clusters of kids around the field and encouraging them – while also teaching and enforcing rules.  By mutual, unspoken consent, the two ‘opposing’ coach/referees also worked to make sure that no team or player was able to dominate the game.  After all, the goal was to make sure all the kids were having fun and were excited to keep playing.

In many ways, that coach/referee role at soccer games was the same role I was playing as a prairie land steward.  At the soccer field, I substituted players on and off the field or shifted them from offense to defense (not that there was much distinction at that age).  I wanted the strong players to score and enjoy themselves, but I didn’t want them to hog the ball so much other players got bored or frustrated.  In the prairie, I was using fire, grazing, mowing, and herbicides to manage plant competition and prevent any species from dominating too much.  I was also trying to create a broad variety of habitat conditions around the prairie so animals could find the resources they needed to compete at their best.

As I’ve learned more about prairie species and ecology, I’ve also improved my ability to recognize and manage competition among ‘players’ in the prairie.  The more plant species I’ve learned to identify, the better I’ve gotten at evaluating their responses to each other and to various management actions.  I’ve also become more familiar with animals beyond birds and other common vertebrates.  As that’s happened, I’ve started to see prairies through the eyes of bees, spiders, grasshoppers, and other creatures.  Improving my understanding of their needs and abilities has made me better at providing what they need to be most successful.

I’m still learning about Canada goldenrod (Solidago canadensis) and trying to understand how it plays with others in our local prairies but it doesn’t appear to tolerate being heavy defoliated. While cows don’t ordinarily like it much, they’ll graze it when we manage with patch-burn grazing or similar shifting-mosaic approaches. Over the years, goldenrod seems to become much less dominant under that management.
There are lots of different grasshopper species (well over 100 in Nebraska) and they differ widely in diet and habitat preferences. However, large patches of bare or sparsely vegetated ground can attract abundant grasshoppers, which (in addition to being important and fascinating creatures) are vital food sources for birds and many other animals.

Every land steward manages competition, even if they’re trying to optimize production of one thing (e.g., corn, grass, pheasants, or rare plants).  In that case, though, instead of working to balance competition and keep as many players on the field as they can, they’re playing favorites.  There can be good reasons to do that, but it can also be dangerous if unbalanced competition starts to reduce the diversity and resilience (and thus the consistent productivity and function) of the system supporting that favorite species or group. 

Big bluestem can form dense near-monoculture stands after fire in our local prairies. Grazing after fire can counter that response, however, and encourage strong plant diversity.
Each of the wildflowers and grasses in this prairie respond somewhat differently to fire and grazing management, but an approach that varies management pressure and timing from year to year can help keep all them around (along with a vast network of large and small animals that depend upon each species).

Regardless of management objectives, the more you know about the players in the game, the better manager you’ll be.  If you can’t tell one species from another, you won’t be able to see how the composition of a community changes over time.  If you can’t detect change, you can’t evaluate the impacts of your management decisions.  Once you recognize a species, you can also start to watch what it does, how it interacts with its surroundings, and how its population fares as conditions shift.

Grassland birds like this western meadowlark have fairly well defined habitat needs, but it’s important to think beyond birds, whose presence and abundance is largely determined by prairie size and vegetation structure.
This moth was feeding on – and potentially pollinating – a milkweed flower when this crab spider captured it. Learning about these kinds of complex interactions between species helps managers make better decisions.

None of us will ever become familiar with identities and lives of all the species that live in our sites, but that doesn’t mean we shouldn’t learn as much as we can.  Take the time to go to workshops and hang around with people who know what you don’t.  Spend some time wandering the sites you manage instead of just traveling across them to accomplish specific tasks.  Yes, you’re busy; I don’t know any land steward who thinks they have enough time to do everything that’s needed.  Find time anyway.  It matters.

Finally, whether you’re fairly new to land management or an old salt, don’t let incomplete knowledge paralyze you from taking action.  Do your best to balance competition as you understand it and pay close attention to the results.  If you notice any players consistently getting the upper hand, adjust your strategies accordingly.  It’s a long game; we just have to keep as many players in it as we can.

Photos of the Week – April 29, 2022

Wildflowers are back! Sure, there have been a few flowers here and there, but during the last week or so, color is really starting to ramp up in my local prairies. Finding those flowers is still a little like an Easter egg hunt, but the challenge rating of the game is decreasing significantly. I made the rounds of my three favorite local sites this week: my family prairie, Prairie Plains Resource Institute’s Gjerloff Prairie, and The Nature Conservancy’s Platte River Prairies (not in that order). Here is a big batch of wildflower photos from those three sites.

We’ll start with three photos of ground plum (Astragalus crassicarpus) at our family prairie. There are a couple big patches of this plant, as well as lots of scattered individuals, and they were all in full bloom last Saturday. The wind was howling, but by being patient (and taking even more shots than I normally do) I was able to get some sharp ones.

Ground plum (Astragalus crassicarpus). Nikon 10.5 fisheye lens. ISO 320, f/18, 1/200 sec.
Ground plum. Nikon 105mm macro lens. ISO 320, f/16, 1/320 sec.
Ground plum with last year’s pods under a barbed wire fence. Nikon 10.5 fisheye lens. ISO 320, f/18, 1/160 sec.

Tuesday morning, I was at the Platte River Prairies to set up a research project, but I arrived extra early to catch the sunrise. I was planning to find some puccoon, pussytoes, and/or violets to photograph, but wild plum called to me as soon as I arrived, with both abundant blossoms and a strong beautiful scent. The warm early morning light worked really well with the flowers and the breeze hadn’t picked up too much yet, so I got lots of nice photos. These are just a few. I tossed in a sedge photo too, just for something different.

Wild plum (Prunus americana) blossoms. Nikon 105mm macro lens. ISO 320, f/13, 1/250 sec.
Wild plum blossoms. Nikon 105mm macro lens. ISO 320, f/13, 1/250 sec.
Wild plum blossoms. Nikon 105mm macro lens. ISO 320, f/13, 1/200 sec.
Wild plum blossoms. Nikon 105mm macro lens. ISO 320, f/16, 1/200 sec.
Spikerush sedge (Carex eleocharis). Nikon 105mm macro lens. ISO 320, f/9, 1/320 sec.

Finally, Wednesday was breezy, but not windy, and there was a very light veil of clouds across the sun. I was taking a vacation day to work on projects around the house, but took a break from my vacation day to drive north to the loess hills of Gjerloff Prairie by Marquette, NE. It was well worth the trip – as always. The remainder of these photos are from Gjerloff Prairie.

Blue violet (Viola missouriensis). Nikon 105mm macro lens. ISO 320, f/16, 1/400 sec.
Prairie dandelion (Nothocalais cuspidata) and a tiny bee. All these plants are very short this year – I’m assuming that’s a drought effect. Nikon 10.5mm fisheye lens. ISO 320, f/16, 1/500 sec.
Prairie dandelion anthers. Nikon 105mm macro lens with Raynox dcr-250 macro attachment. ISO 320, f/11, 1/800 sec.
Prairie dandelion with a loess bluff in the background. Nikon 10.5mm fisheye lens. ISO 500, f/22, 1/250 sec.
Platte milkvetch (Astragalus plattensis) on a dry loess bluff. Nikon 10.5mm fisheye lens. ISO 320, f/22, 1/160 sec.
Carolina anemone (Anemone caroliniana). Nikon 105mm macro lens with Raynox dcr-250 macro attachment. ISO 500, f/13, 1/2500 sec.
Carolina anemone. Nikon 105mm macro lens with Raynox dcr-250 macro attachment. ISO 320, f/18, 1/400 sec.
Carolina anemone. Nikon 105mm macro lens with Raynox dcr-250 macro attachment. ISO 320, f/14, 1/400 sec.

Apart from the plum and ground plum flower photos, all the others here were taken in sites that were grazed hard last year and entering a year of recovery. I’m not seeing much flowering in ungrazed areas so far, and this spring’s drought and wind have prevented any burning. The reduced light and cooler soils beneath the thatch and standing dead vegetation is pretty hard on many spring wildflowers. While these particular ground plum photos were from an ungrazed part of our family prairie, they were blooming in dry, low productivity soils that keep grass growth to a minimum.

Carolina anemone, in particular, seems tied to prairie patches that were either summer burned or grazed the previous year. I say that, but there’s got to be more to it because I’m really bad at predicting where I’ll find them. It’s always someplace with short grass, but it seems like I find new populations each year and rarely find flowers where I’ve seen them in previous years, even following management that I expect to encourage them to bloom. These are perennials, so you’d think they’d be more predictable. Well, maybe you wouldn’t, but I would. I see the same unpredictability at all three of the prairies I visited this week, as well as in my yard, where I’ve got a few plants I can keep a close eye on.

I did manage a few insect photos this week too, but stuck to a mainly wildflower theme for this post. I was really happy to see as many bees as I did, though, along with flies and a few moths and butterflies too. After weeks of blistering winds, I was starting to worry that flying insects would be grounded and end up starving to death. That’d obviously be bad for both pollinators and flowers. I’m still curious to see what seed production looks like from these first spring flowers, but seeing lots of sweat bees, hover flies, and others (including a couple queen bumble bees) this week made me more optimistic than I’d been.

I hope you’re seeing flowers wherever you are too. Have a great weekend.