Bison are pretty tough. At our Niobrara Valley Preserve, and at many other sites in the upper Great Plains, bison make it through the winter without any supplementary feed. They just eat cured grasses, grow a thick coat, and plow through snow and ice as needed. Bison don’t need humans to help with calving, and they protect their babies very effectively from predators. It shouldn’t be surprising, then, that animals like that would be completely unfazed by a little rain.
Yesterday, some of our Nebraska staff took a trip up to The Nature Conservancy’s Broken Kettle Grasslands in the northern Loess Hills of Iowa. Land steward James Baker led us on a very scenic hike before a band of cold rainy weather moved in. We then piled into some trucks with James and Director of Stewardship Scott Moats and went to visit the resident bison herd. The bison were peacefully grazing as we drove up, despite the pouring rain. When we stopped, a small group came over to check us out. Here are a few photos of those rugged bison, who didn’t need to huddle in dry and heated pickups to stay comfortable.
P.S. In case you had any doubt about my nerd qualifications, here’s one more piece of evidence. As I was working up these photos (in the backseat of a truck heading back to Nebraska) yesterday, I was looking closely at the streaks of rain captured by my camera. Based on the size of a bison calf’s eye and the length of the rain streaks closest to those eyes, I estimated that my camera captured about an inch of raindrop fall during the 1/250 of a second the camera’s shutter was open. Now, I’d want to do some actual measuring of bison calves’ eyes to check this, but based on that rough estimation, those raindrops were falling about 250 inches per second. Now, if I convert that number to miles per hour, I get 14.2 mph. A quick online search found that raindrops are estimated to fall at about 20 mph. I was pretty close!! I mean, given that I don’t really know how big a bison eye is or how close those raindrop streaks were to that eye… (NERD)
One of my favorite aspects of my square meter photography project has been the chance to closely follow the lives of individual organisms over time. For example, I’ve closely followed the progress of the two butterfly milkweed (Asclepias tuberosa) plants within the boundaries of my square meter plot. The plants bloomed beautifully back in late June, which was great, though fewer pollinators visited the flowers than I had hoped. Perhaps correlated with that, only one seed pod was produced between those two plants. Since then, I have been watching that one pod very very closely…
This week, that pod finally opened up, giving me the long-awaited chance to photograph some milkweed seeds within my plot. As it turns out, it’s a good thing I was vigilant, because that pod opened up and emptied itself out out very quickly. Within only a few days, the pod went from tightly closed to completely devoid of seeds.
While many of the seeds were blown well out of my little plot, a handful got stuck on adjacent plants, giving me the chance to photograph them. Here are some photos of those seeds as they were coming out of the pod or after they got hung up within the borders of my plot.
This post was written by Olivia Schouten, one of our Hubbard Fellows this year. Olivia is an excellent scientist, with strong expertise in plants and plant communities, as you’ll be able to see from this post.
As a biologist with broad interests, I can usually find something to love in all living things, but I’ll admit that plants have a special place in my heart. This is probably a good thing, since I’ve spent the majority of my education and professional life cultivating my knowledge of plants. I’ve found that they are often underappreciated and often overlooked, which is a shame, because plants are some of the most amazing organisms out there (in my humble opinion).
Plants, in most places, not only form the basis of the food chain, but also provide the structure of habitat. A forest with towering trees is very different than an open grassland or a sparsely vegetated desert, and the animals that live there respond accordingly. Plants are eaten, trampled underfoot, exposed to the whims of the weather, and just generally beaten down by the world around them, all on top of competing with each other for resources and space. But while plants have it rough, they are also really good at persisting.
Trees are an excellent example of just how persistent plants can be. I was reminded of this earlier in the summer when I came across a grove of cottonwoods in one of our Platte Prairies while searching for musk thistles. At first glance I thought one of the cottonwoods had recently fallen and the leaves hadn’t died back yet. On closer inspection, however, I realized that the tree had probably fallen years ago, and instead of dying, the parts of the trunk that now contacted the earth had sprouted roots and continued on living. Branches had grown up from the trunk,and now looked essentially like three trees, all connected by the same fallen trunk.
Trees are clearly hard to kill, as anyone who’s tried to cut down a deciduous tree in your yard knows. Once the tree is cut you have to treat the stump with herbicide, otherwise the still-living roots will simply sprout again. Nearly every tree we cut here on the Platte to keep our prairies open needs to be treated with an herbicide. While it would be nice to not have to use chemicals in our stewardship work like this, that resilience of trees can also be a blessing. After the wildfire at our Niobrara Valley Preserve a few years ago, much of the forest along the river was killed. However, the oaks along the slopes are re-sprouting from their roots, as only the tops of the trees had been killed in the blaze. Because of this, these forests have a jump start on regenerating after the devastation of the fire.
Since I found that cottonwood looking for musk thistles, it’s probably worth talking about them and their own resilient strategies. As a biennial, these plants only have one chance to flower and produce seeds, so they produce thousands of them at a time. And they can fly. That’s not great for us, considering they are considered noxious weeds here in Nebraska, but as a strategy for this plant it certainly pays off.
But wait, there’s more! Even when uprooted or sprayed with herbicide, if the flowers on a musk thistle plant have been pollinated, they will still produce seeds! So when we control this plant, we not only cut off the root just under the ground and pull it out, we have to collect any flowers, or else nothing will actually have been controlled. This persistent ability of musk thistles makes things more difficult and time consuming for us to control, but you have to admit that it’s a cool adaptation, and in its native habitat, likely very useful.
So far these examples relate back to land management, and how the difficulty in killing plants affects our ability to effectively manage invasive plants in prairies. But we rely on these same tenacious qualities in our native prairies species as well. Chris talks a lot about the resilience of prairies on this blog, and a lot of that depends on the persistent nature of individual plants.
Consider big bluestem, a favorite of both cattle and bison. It can be cropped down again and again to within an inch of the ground over a growing season, but while such trauma might kill another plant, big bluestem holds on until the herd moves on and it gets a break, coming back taller and stronger the next year, until it’s back to full strength within a few years. In addition, even in those years that it’s hammered by grazing, big bluestem will find a way to flower, since all that short and weak vegetation around them makes for a good place to put out seeds.
Other plants may just find that conditions in a certain year aren’t for them. Maybe it’s too dry, or too cold, or the grasses around them are just too tall. Perennial prairie plants don’t let that stop them, as many will simply take a break, growing very little above ground for a year, relying more on stores of energy in their roots than anything else. To some, it may seem like those plants have died and disappeared from a field. But just wait, when conditions become favorable, most of those plants will show up again, just as strong, and benefiting from that strategy of waiting it out through the hard times.
Now, just because plants are tough doesn’t mean they’re invincible. If put under too much stress even the most stubborn plant will eventually die. Knowing how plants are able to persist can help us more effectively target those plants we don’t want, but also help ensure that our desirable plants always have a chance to let their persistent nature shine!
I spent much of this week in northern Nebraska, attending various events and staying at the Niobrara Valley Preserve. It rained much of the time, but I caught a break in the clouds Monday evening and happened upon the bison in our east herd as the sun was going down. I spent about an hour and a half tagging along with them as they moved slowly toward the setting sun. If you haven’t spent much time with bison, one of the things you notice immediately is how quiet they are. Apart from some contented grunting, the primary sounds I heard as I accompanied them was the crunching of their hooves in the grass and the sound of them tearing mouthfuls of food from the prairie. It was very peaceful, and provided the perfect accompaniment to the sun going down over the hills.
Well, August was an awesome month for my square meter photography project. An unbelievable number of insects visited my little plot of prairie during the month, many of them drawn by the abundant and very charismatic Maximilian sunflowers. After a lot of sorting and decision-making, I ended up with well over 150 high quality photos from the month. I’m sharing 18 of those with you here.
I started this project with the hope of inspiring people about the beauty and diversity of prairies. What I didn’t expect was the degree to which I, myself, have been inspired and affected by the project. The diversity of life I’ve recorded has been amazing, but the process of slowing down, focusing in, and appreciating what I find in a tiny space has become a powerful experience for me. Rather than feeling like I’m missing other photographic opportunities by returning over and over to the same little spot, I actually find myself wishing I was there when I’m not.
Anyway, I hope you’re enjoying these updates along the way. I’m working on some ideas for how to share the entire project after the year is over. If you have suggestions along those lines, please feel free to share them!
Science doesn’t have to be complicated or difficult. In fact, the essence of science is really just a way to satisfy our curiosity about the world.
There is great value in rigorous science, with sufficient replication and statistical power to merit publication in peer-reviewed journals. That kind of science moves us forward as a scientific community, and provides checks and balances to make sure we don’t go too far down the wrong path. At the other end of the spectrum, however, is the kind of science that any naturalist or land manager can use to answer basic questions about how the world works. An observation triggers a question, and more observations help answer that question.
Exactly one year ago, I posted the results of about a half hour’s worth of data collection on dotted gayfeather (Liatris punctata) plants. I had noticed that plants in one part of one of our restored Platte River Prairies seemed to have a lot more flowering stems than in another part of the same prairie. It was pretty easy to walk around and count enough stems in both patches and see if my observation could be confirmed by data. It was. Gayfeather plants growing in the half that had been burned and grazed intensively during the previous year had many more flowering stems than those growing in the half that hadn’t been burned and was only lightly grazed.
At the time, I speculated that perhaps the reduced competition from grazed/stressed grasses had allowed the dotted gayfeather plants an opportunity to produce a lot more flowering stems. You can read last year’s post for more details on my hypothesis, if you like, but in that post I’d promised to revisit the site again in future years to see if patterns of stem abundance fit my guess.
Well, I kept my promise yesterday, and the results are very interesting!
The above graph shows averages based on counts of 58 and 63 plants from the east half of the prairie in 2017 and 2018, respectively. In the west half, I counted 53 plants in 2017 and 43 in 2018 – it was harder to find flowering plants in 2018, making me wonder if some didn’t bloom or if they were just hidden in the dense grass (or both).
The west half of the prairie, was burned/grazed in 2016 and had very high numbers of gayfeather stems/plant in 2017. It was completely rested from grazing last year and is only getting very light grazing pressure in 2018. As a result, grasses have recovered very well, and now grow pretty thickly around the dotted gayfeather plants. My prediction was that as grasses recovered, the number of gayfeather stems would decrease. They did. In 2017, I was finding a lot of plants with stem numbers in the 20’s and 30’s, and one gigantic plant had 51 stems! In the same area a year later, I found one plant with 21 stems and all the rest had 10 or fewer (most had 3 or fewer).
Meanwhile, the east half was burned this spring and has been getting pretty intensive grazing all season long. Cattle have been mainly focusing on grasses like big bluestem and Indiangrass. It’s pretty similar to the way the west half was grazed in 2016, though this year’s high rainfall has let some grasses grow faster than the cattle can eat them. As a result, the overall grazing intensity – and the stress on grass plants – won’t be quite as strong as it was when the west half was grazed in 2016, but I’m hoping it will be enough that grasses will be much less competitive in 2019. If so, and if my hypothesis is right, I should see gayfeather stem numbers go way up in 2019 in this area.
So far, I’ve invested about 2 hours worth of time on this project. That includes about 30 minutes of data collection each year (walking around and counting stems on all the plants I encountered) and about the same amount of time entering the data and creating a graph. Despite that, I’m gaining confidence that my initial hypothesis about grass competition and gayfeather stem numbers was on the right track. A year from now, if gayfeather stem numbers increase dramatically in the east half (burned and grazed this year) and stay about the same in the west, I’ll be pretty confident in my answer.
Now, my results aren’t going to cure cancer or likely change the world in any measurable way. I probably won’t submit my results to a peer-reviewed journal (although I might actually submit a “note” if the results warrant it). On the other hand, I’m learning a lot, and what I’m observing is a small clue to a larger puzzle. I’ve got years of much more rigorous data showing that short-lived wildflowers respond very positively after grazing reduces the vigor of competing grasses. That wildflower response, however, has mostly been from the germination of new plants that fill in while grasses are weak and then die out again as grasses retake their previous territory.
My observations of dotted gayfeather are giving me some intriguing insight into how long-lived perennial plants might respond to the same reduction of grass competition. It appears likely that at least some long-lived plants are able to take advantage of that lighter competition by producing many more stems, leaves, and flowers. That increase must certainly benefit pollinators, and maybe other organisms that feed on gayfeather. Is it also important to the long-term survival of the plants? Good question! The plants sure create a lot more seeds when they make more flowers. It would be really interesting to know if the plants also produce a bonanza of new buds at their bases (those buds are what allow them to grow new stems in the future).
Remember – this whole story started because I happened to notice a lot of flowers in one part of our prairies and took 30 minutes to count them. That kind of cyclical curiosity and observation is the foundation of science, and is the reason we’ve learned what we have about the world around us. Who knows – maybe my little gayfeather project will lead others to build upon my observations with a more rigorous project that will lead to greater understanding of plant communities, competition, and response to grazing and other stresses. Whether it does or not, I’m already getting what I wanted out of the project – I’m having fun, learning something new, and stimulating my brain to come up with more questions about the prairies I love.
What are you seeing? What kinds of questions are tickling your brain as a result? Do you have a spare hour or two to explore a little further? Think of what all of us could be learning with just a little bit of time and effort!
Former Hubbard Fellow Evan Barrientos came back for a visit last week and the two of us wandered around with our cameras for a couple hours on a wet foggy Saturday morning. (Quick reminder – applications for the next round of Hubbard Fellows are being accepted NOW – click here for more information.)
It was a beautiful morning, and we spent the bulk of our time in a prairie Evan had helped create while he was working for us. Despite its young age (3rd growing season), the prairie already has a lot going on. Plant diversity is looking good and invertebrates seem to be colonizing nicely. Among those colonizers are a lot of spiders, and a foggy morning is a great time to see and photograph spider webs. I spotted webs of several different species, but ended up photographing mostly webs created by a couple different species of (I think) longjawed orb weavers (Tetragnatha sp.). I photographed much more than just spiders during those couple hours, but some of the longjawed orbweaver shots ended up being my favorite images of the day.
The following three photos were taken within a minute or so of each other. I couldn’t decide between them, so have included all of them. I’m curious to know if any of you have strong preferences between them. I think I like the first and third best, though the second is really nice too. See what I mean?
The pose of this spider is common among many skinny long-legged spiders. When inactive, or in the presence of a potential threat, they cozy up to a grass leaf or plant stem and almost seem to melt into it. This one was in its hiding pose when I first spotted it. Judging by the dew droplets still affixed to its legs, I’m guessing it spent the night in that pose, but I’m not sure.
Between the first and second photo, I carefully held out my hand near the web and the spider shifted slightly away from it, moving a little more toward my camera, and into the light. This is a really handy trick for slightly repositioning insects and other invertebrates for photos. It always works spectacularly, except when it fails even more spectacularly and the subject hops, drops, or otherwise flees.
As I was photographing the spider in its new, more illuminated position, it suddenly stretched out its legs – as if it was yawning. I squeezed off a couple quick shots before it returned to its original position.
The chance to photograph spiders on dew-covered webs always feels like a gift. The conditions have to be just right – including near-zero wind velocity. Late summer seems to be the time when an abundance of spider webs corresponds with an abundance of calm foggy/dewy mornings. On those mornings, I tread carefully through prairies, trying hard not to blunder through webs, but knowing I will anyway. I find most webs by looking toward the sunlight so that the glowing backlit dew-covered orbs stand out against a darker background.
Most webs are close to the ground, surrounded by tall vegetation, making them nearly impossible to approach without jiggling the web, and either breaking it or scaring the spider away – or both. To add to the difficulty, most spiders sit on the downward slanting side of their web, with their eyes facing down and away from the sun. I always like to feature the faces of invertebrates when I can, but it’s not always possible to find a camera angle that works with web-weaving spiders.
The first three photos above were taken of webs that were along a restored wetland swale, where vegetation was relatively thin and I could fairly easily slide my tripod close to the spiders. The last three were of a web that was placed at nearly head height – something I don’t see very often.
Oh, I did take photos of Evan too, but he wasn’t covered in dew and sitting on a glistening orb-shaped web, so he didn’t make the cut for this blog post.
Japanese beetles (Popillia japonica) first appeared in the U.S. back in 1916 (in New Jersey) and have been spreading west since then. They’ve only started to be abundant in our part of Nebraska during the last several years. As a result, I’m not really sure what to expect in terms of potential impacts to our prairies. I’m largely writing this post to hear what my friends to the east have been seeing, since the little buggers have been around there longer.
While I’m not sure what to expect in prairies, our family has had plenty of experience with their ability to damage our garden crops. Japanese beetles wiped out our raspberry crop last year and were trying really hard to kill our little apple tree this year. I’m not a fan.
For those of you not familiar with Japanese beetles, they are about 1/2 inch long beetles that are metallic green with brown wing covers. The series of white spots around the edge of their abdomen are actually little patches of white hairs, and those help distinguish them from lots of other metallic green beetles. The larvae feed mostly on the roots of grasses, and they are a big pest in lawns and other turfgrass situations. As adults they’re known to attack over 300 different plant species, with corn, soybeans, maples, elms, plums, roses, raspberries and grapes among their favorites. Hence, they are pretty unpopular with gardeners and farmers alike.
Adults emerge in the early summer and seem to spend the vast majority of their time eating and mating – often at the same time. Females take breaks from feeding/mating to burrow a few inches into the soil in grassy areas and deposit a few eggs. Then they come back out and join the crowd again for a while. They can repeat their burrowing/egg laying up to 16 times a season. Most adults live for about a month or month-and-a-half, but some can live up to 100 days or more. They are skeletonizers of plants, meaning that they feed on the portions of leaves between the veins, leaving behind only the skeletons of those leaves.
I’ve been trying to pay attention to Japanese beetles in prairies, but I don’t feel like I’m learning very much yet. The biggest infestations I’ve seen have been in the small prairies here in Aurora (Lincoln Creek Prairie). In bigger prairies outside of town, I don’t see nearly as many. At Lincoln Creek, the beetles feed on a lot of different plants, but seem to have special attraction to tick clovers (Desmodium) and the flowers of roundheaded bushclover (Lespedeza capitata). However, while I’ve seen many plants nearly covered with beetles, many others manage to successfully bloom and make seed, so I don’t yet see the beetles having any major impacts.
Help? What are those of you in the Midwest and further east seeing in prairies that have had decades or more of Japanese beetle infestations? Any evidence that they might wipe out particular plant species? Should we be concerned about them in our Nebraska prairies or just focus on protecting our gardens and crop fields?
The square meter photography project continues! Throughout this calendar year, I’m trying to document as much beauty and diversity as I can within a single square meter of prairie along Lincoln Creek in Aurora, Nebraska. Today, I’m sharing some of my favorite images from July. If you want to look backwards, you can click to on these links to look at selected photos from June, May, and January.
July was a little slower than I’d expected, to be honest (August, however, has been really hopping). I was surprised how few pollinators showed up to feed on the butterfly milkweed plant in my little plot. (I’m sure it didn’t have anything to do with the loony guy and his camera looming nearby. There were lots of insects hanging around on butterfly milkweed plants elsewhere in the prairie…) Regardless, there was still plenty going on in the plot last month. Here are some highlights.
Another month has passed, and I’ve managed to carve out some more time staring at the little square meter of prairie I’m photographing this year. In June, activity really picked up as lead plant (Amorpha canescens) and butterfly milkweed (Asclepias tuberosa) started blooming within the plot. However, there was plenty to photograph besides just those species and the many insects they attracted. I continue to be inspired by the diversity of life I’m finding in a very small plot of land. Hopefully, I can pass along some of that inspiration, both during these periodic updates and when I somehow assemble all of this at the end of the project. Here are just a few of the photos taken during June within one single square meter of Lincoln Creek Prairie in Aurora, Nebraska.