Hello from Wisconsin! I’m spending this week in Madison, Wisconsin with about 250 colleagues at a conference for scientists, land managers, and other conservation staff of The Nature Conservancy. It’s been a fantastic conference, but also an awful lot of time spent with crowds of people – something that drains me after a while. As I write this, I’m holed up in my hotel room, grabbing a little peace and quiet before heading to supper.
Because I’ve been busy with the conference all week, I haven’t done much photography (and I really miss my square meter plot!) but I did manage a few photos during our Tuesday field trip west of Madison. We had a few minutes to wander after arriving at our first stop, and I stopped to admire numerous Argiope spiders on their webs. Even after our tour leader started talking, I wandered around the edge of the group – staying within earshot – and looked at some more spiders. I hope I didn’t come off as rude, but the spiders were really pretty, and a few let me get within photo range.
Not long after I took these photos, the sunlight became too intense for good close up photos so I rejoined the tour group and behaved myself. There is great conservation work going on in the Military Ridge area, with a great set of partners working together. It is one of the best remaining landscapes in Wisconsin for grassland birds, and still has fairly stable populations of regal fritillary butterflies and other species. Eric Mark with The Nature Conservancy is doing some grazing work to manage bird and butterfly habitat, and is working hard to build ties with the local community. The local chapter of The Prairie Enthusiasts is doing some tremendous prairie restoration work, converting brome fields to diverse prairies. Those and other partners, including state, federal, and non-profit organizations, seem to have a strong and positive working relationship.
One of the most striking plants in our prairies this time of year is pitcher sage, also known as blue sage (Salvia azurea). It’s tall, of course, but more importantly, as the surrounding prairie is dominated by green-becoming-gold grasses and big yellow flowers, pitcher sage stands out simply because it is starkly and unabashedly blue.
A few weeks ago, I posted a photo of a bee that specializes on pitcher sage, but there are many more insects commonly seen on the plant. Last week, I spent about 45 minutes in our Platte River Prairies, photographing pitcher sage and as many visitors as I could.
I initially pulled my camera out because there were several monarch butterflies flitting around a patch of pitcher sage. While chasing them around (and, as always, being thankful no one was watching me), I came across quite a few other insects – some of which I managed to photograph.
In addition to being tall, striking, and beautiful, pitcher sage is also pretty good at withstanding drought. During late August of 2012 – a year of extreme drought, pitcher sage stood out against a background of brown dormant grass, blooming just like it does every year. Not only did it provide some welcome color when many other plants were wilting, it gave all the insects pictured above, and many others, something to eat when they needed it most.
Alex Brechbill, one of our Hubbard Fellows, is conducting a survey to help us improve visitor experiences at our Platte River Prairies. If you’ve ever visited the Platte River Prairies to hike, volunteer, attend one of our field days, or for any other purpose, please consider taking the survey.
If you’ve never come to the Platte River Prairies, but you think you might someday, your input would also be welcome. The survey is designed for both former and future visitors. Please tell us what would make your experience better. (Also, check out this page to find out more about our public trails).
You can take the survey by clicking HERE. And thank you.
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!
Earlier this week, we spent a few days collecting data at the Niobrara Valley Preserve. It was a quick trip up and back, but we still managed to see quite a bit of wildlife, including mule deer, pronghorn, grouse, lizards, monarch butterflies, lots of grasshoppers and bees, and much more. We also found ourselves close to bison a few times, and I managed to get some decent photos of them. Here is a selection of those bison shots.
During the last month or so, I’ve had several people tell me how aggressive marestail (horseweed, aka Conyza canadensis) is, and how this is a particularly bad year for it. One person suggested marestail should be added to Nebraska’s noxious weed list. This week, Olivia and I drove from our Platte River Prairies to the Niobrara Valley Preserve – right through the center of our state – and I tried to document what is certainly a summer of abundance for marestail.
Here are a few things you should know about marestail right off the bat. First, it is native to Nebraska and most of North America. It acts as an annual plant in states to the east of us, but acts as a biennial here, usually germinating in the fall and blooming the following summer. In its native habitats (including grasslands), marestail is a colonizer of bare ground, filling spaces between plants left open by disturbances like grazing, trampling, animal burrowing, drought, or fire. Because marestail loves open soil conditions, it isn’t surprising that it has become a weed in crop fields. It has garnered special attention lately because it has a strong ability to become resistant to herbicides, including glyphosate, which it started showing resistance to way back in 2006.
In other words, marestail is a tough native plant that has always scraped out a living when and where it can. However, it’s not a plant that can push other plants around. Instead, it sits in the soil (as a seed) and waits for a time when surrounding plants are weakened and abundant light is hitting the soil. Then it pops out of the ground and tries to grow, bloom, and produce as many seeds as it can during its short window of opportunity. In any particular year, marestail can be found here and there in most Nebraska prairies, especially those in the western 2/3 of the state. However, it also seems periodically to respond to certain weather patterns and exhibit a flush of abundance across a larger region – as it is doing this year. Many short-lived plants do the same thing, each with its own individual preferences for weather patterns. Many Nebraskans might remember the huge sunflower party across the Sandhills back in 2013, for example, following the big drought of 2012.
Whether it’s sunflowers or marestail, huge regional flushes in abundance don’t last long. By 2014, annual sunflower numbers in the Sandhills had returned to normal – patches of yellow flowers here and there, around livestock tanks and fence corners, and wherever else there was open soil to grow in. Marestail will do the same thing in 2019. That pattern of boom and bust is not evidence of an invasive plant. Instead it characterizes a plant that is too weak to compete most of the time and has to take ultimate advantage of the few windows of opportunity it gets. When it is abundant, marestail isn’t stealing resources from other plants, it is taking resources that weren’t being used. I don’t know for sure what weather patterns led to rampant marestail germination last fall, but I’m sure this year’s abundant rains have played a big role in the survival of a large percentage of those seedlings.
When short-lived plants like marestail and sunflower (along with ragweed, gumweed, and many more) are in the middle of a short-term explosion in your prairie, you could choose to fight them. You could, for example, mow them off, trying to prevent them from making seed. However, that’s a lot of work, and the plants will do everything they can to regrow and still produce seed – it’s what they do, and they only get one year to do it. Even if you do keep them from going to seed, there are many thousands of seed already in the soil, ready to spawn the next generation of plants whenever they get the chance. You could also spray short-lived opportunistic plants with herbicide, but I wouldn’t recommend it. First, you’ll likely kill the surrounding plants (the ones that normally out-compete marestail and sunflower) and just trigger another explosion of opportunistic plants the f0llowing year. Second, with most short-lived plants, by the time they’re big enough that you notice them (especially by the time they’re flowering) herbicide treatments just make them produce seed more quickly, so are counterproductive.
The smartest choice is to just sit back and marvel at these periodic phenemona, knowing you’re watching a short-term and harmless event. Marestail, of course, doesn’t have the wide aesthetic appeal of sunflowers (though not everyone likes sunflowers either), but it has its own distinctive charm. I think it adds an attractive texture to the landscape, but I’ll admit I’m a little odd. Regardless of whether you find it attractive or not, it’s here, and it’ll be here whether you like it or not.
Fighting back against these periodic flushes of marestail and other opportunists is expensive and futile, and usually results in weakening the plant community that normally keeps them in check. Most importantly, remember that, at least in grasslands, marestail doesn’t steal resources from the plants you like, it just takes what they can’t use. What’s to dislike about that?
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?
I’ve been spending a lot of this summer at Lincoln Creek Prairie, right across town from my house. Much of my time there has been spent working on my square meter photography project, but I’ve wandered a lot through the rest of the prairie as well. Visiting the same site frequently always helps me appreciate the dynamic nature of prairies. I get to track individual flower blossoms as they transform from buds to blossoms to seed heads, and watch insects move from larva/nymph stage to adult.
Last weekend, for example, I visited the prairie two days in a row and spotted four different Chinese mantises that had just emerged from their last molt, leaving their exoskeletons behind. I don’t think I’ve ever seen one of those exoskeletons before, let alone four over a two day period. I’m guessing the skeletons don’t usually hang around long before they fall, dry up, and shrivel into obscurity – not necessarily in that order.
One of my most exciting finds at Lincoln Creek this month was a small bee with gorgeous blue eyes. It was a male Tetraloniella cressoniana – something I know only because I sent the photo to Mike Arduser for identification. I’ve photographed this species once before, back in 2009, and I wrote about it in a 2011 blog post. The bee is noteworthy because it is very specialized in diet – feeding only on pitcher sage, aka blue sage (Salvia azurea). Not coincidentally, that is the flower species in both pictures I have of this species.
Ever since learning about the species from Mike, I’d been hoping to see and photograph it again. I finally got my wish last week, on a dewy morning at Lincoln Creek. The bee was poised on a blue sage flower, probably waiting for the prairie to warm up and dry out enough that females would emerge from their nests. I took quite a few shots of it as I gradually edged closer and closer, until it nearly filled the frame. As soon as I got home, I fired off one of the photos to Mike, who enthusiastically identified it for me.
Dewy mornings have always been favorite photographic opportunities for me, especially when the wind is calm. Insects get trapped in dew drops, making them easy to photograph, and the entire prairie glistens and sparkles as the first light of the day hits it. Photographing individual dew drops is always alluring, but rarely turns out very well for me – my macro lens doesn’t magnify them enough for my taste, and depth-of-field issues and slight breezes increase the technical difficulty significantly. Now and then, however, I find the right situation. That happened last week with a big droplet near a patch of sensitive briar flowers.
Lincoln Creek Prairie has been a favorite spot of mine since I moved to town over 20 years ago. It’s only about a mile from my house, and is a nice restored prairie with lots of flower and insect diversity. The prairie is small and subdivided by tree lines and roads, but none of that really affects close-up photography. Despite having made hundreds of trips to the prairie before this summer, though, I’m still finding new subject matter and making new observations – showcasing beautifully what prairies are all about.