The Value of (Some) Non-Native (GASP) Wildflowers in Our Yard

This might be an awkward week to laud the value of having a non-native wildflower in my yard. I’m an invited speaker at the Indiana Native Plant Society’s annual conference this coming weekend. It’s probably (?) too late for them to cancel my appearance.

I’m mostly kidding. Today’s post is not intended to diminish the importance of native plants, either in ecological restoration or in suburban landscapes. I’m (obviously, I hope) a huge advocate for including native plants in those situations for many reasons. I’ve written about that before (here) and don’t need to cover that ground again here. However, in that same post, I also explained why Kim and I have a mix of native and non-native (and even some cultivars of native plants) in our yard. If that makes you feel agitated, I beg you to read both that post and this one before you start stomping your feet and plotting my destruction.

Monarch butterfly on a zinnia flower this week.

We moved across town last winter, abandoning garden spaces Kim and I (mostly Kim) had invested 10 years in. Our new place is mostly Kentucky bluegrass with some minimal and mostly not-our-style flower gardens along the edge of the house. While we’re both antsy to start making it ours, Kim very rationally decided that we need to wait a year before jumping into a new landscape plan. That’ll give us (her) time to scope out the sunny and shady spots, learn about what’s already here, and think about what we really want this new yard to look like.

As a result, we (she) planted a small vegetable garden in the same footprint used by the previous owner, but otherwise – with one exception – left the rest of the yard as is. That exception was that she planted a bunch of zinnias around our back deck and in a stretch of space on the west side of the house. I’m grateful for a couple reasons. First, zinnias are beautiful and I like looking at them. Second, and (finally) getting to the point of this post, they attract and feed a lot of insects, including lots of migrants. In particular, this week, they fed a couple butterflies that weren’t really supposed to be here, but showed up anyway.

Our dog, Fitz, posing with some of our zinnias.

We’ve been enjoying a bounty of pollinators and other insects on our zinnias all season. During the last few weeks, though, the activity has been even more appreciated because most of the native plants in nearby prairies and other natural areas have pretty much shut down for the season. There’s very little available pollen and nectar out there right now. In our yard, though, the zinnias are still cruising along.

While most monarchs have scooted south, the few that are still hanging around and/or passing through have really concentrated their activity on our zinnias. They’re joined by migratory painted lady and American lady butterflies, as well as other butterflies, moths, bees, flies, etc. – some migratory, some not.

Last weekend, I spotted a butterfly on our zinnias that I’d seen in books, but never in real life – a gulf fritillary. I took a couple quick photos with my phone and checked the terrific Nebraska Lepidoptera website to see what I could learn.

According to the website, the species hadn’t yet been reported in our county and it was also outside the seasonal window when it had been reported in the state. That’s pretty cool. I emailed Neil Dankert, who runs the site, to let him know what I’d seen. Apparently, a few other people in the state were reporting the butterflies in their yards, too, along with a few other species that are normally found to our south. We’d had some strong southerly winds (blowing out of the south) a day or two before I saw the gulf fritillary, so maybe a bunch of butterflies just got blown north by that weather system.

Gulf fritillary.
Gulf fritillary.

The next morning, I took my camera out behind the house and took the photos shown in this post. I saw at least two different gulf fritillaries, which I know only because one of them had a wing that was a little beat up. Well, I also saw two at once, which was another good clue, I guess. There could easily have been more than two, though – there was so much activity on the flowers, it was hard to keep track. Here are photos of some of the other insect visitors on the zinnias that morning.

American lady butterfly.
Painted lady butterfly.
Pearl crescent butterfly.
Skipper butterfly.
Soybean looper moth?
Yellow-shouldered drone fly.
European honey bee.

I’m excited to start putting in a bunch of native plants next spring, and building those gardens out over the next several years. We’ll be sure to include wildflowers that bloom at different times of year so that we can provide nectaring options consistently through the growing season for both resident and migratory pollinators. It’ll also be fun to watch myriad insects feed on the leaves, burrow into the stems, and otherwise utilize the plant species they are familiar with and adapted to.

At the same time, though, I’m sure we’ll add species like crocus, daffodil, tulip, hyacinth, and others, just because we think they’re pretty. Zinnias, too, will continue to be a staple of our backyard color. We’ll plant a cherry tree for pies and maybe some raspberries and strawberries for eating and canning. In addition, we’ll leave one fairly big swath of mowed bluegrass so we can play frisbee with the dogs and so there’s a place for kids to play soccer or whatever they want. In short, we’ll create a yard that fits us.

Gulf fritillary and monarch butterfly sharing the same flower (momentarily).

I fully support people who want to turn their whole yard into native prairie plantings, or to landscape with only native plants. If that makes them happy, it makes me happy. I’m a little bothered, though, by the more militant among them who try to shame anyone who doesn’t want to go whole hog with them.

There are lots of ways to contribute to the world with your yard. You can be conservative in your water use, for example, both by planting species that require minimal watering and by not watering more than needed. Leaving piles of sticks and leaves around, as well as patches of bare ground, provide helpful habitat for many species. You can also be judicious about spraying chemicals for weed or “pest” control. The overuse of herbicides and pesticides is a huge problem and has big ripple effects outside of someone’s yard.

And, of course, incorporating native plants in your landscaping has innumerable benefits, both directly to insects and other wildlife and indirectly as a way of normalizing those plant species to neighbors and passers-by. Please add native species to your yard if you can!

However, don’t feel bad about throwing in a few daffodils, petunias, or zinnias as well. I sure don’t, and neither – apparently – do the butterflies.

Learning How to Live With Shrubbier Grasslands – Part 2: Experimentation

In Part 1 of this topic, I wrote about the uncomfortable situation many prairie stewards find ourselves in – that our grasslands are getting “shrubbier” and it’s increasingly difficult to prevent that. Because the drivers for that change are mostly beyond our control, it seems obvious that we need to start thinking differently about grassland management.

There are still plenty of grasslands where we should work to prevent woody encroachment. However, there are also a lot of prairies where trees or shrubs have already become part of the community. In many other places, it appears to be just a matter of time. It seems smart for us to try to get ahead of this and figure out how to manage woodier grasslands for biodiversity and productivity.

Most of us haven’t focused much on how to manage the height and density of shrubs in our prairies because we’ve been thinking mostly about how to repel them. That means we need to start experimenting, and quickly. My team has implemented a couple different field trials in the last couple years and I’m going to share some preliminary results with you. I hope those results will spur others to share their experiences and, more importantly, ramp up their own experimentation efforts.

Our first trials focus on clonal deciduous shrubs (smooth sumac and rough-leaved dogwood). We started with the hypothesis that if we could hit them twice (or more) in the same growing season, we might get multiple years of suppressed height and density as a result. This hypothesis was informed by helpful conversations with people like Dean Kettle at the Kansas Biological Survey and several others.

Field Trial #1 – Smooth Sumac at The Nature Conservancy’s Niobrara Valley Preserve

In 2023, we treated a number of smooth sumac patches with treatments (often in combination) that included prescribed fire, mowing, and a non-lethal “burn-down” herbicide. The photos shown here illustrate what those sumac patches looked like on June 16, 2025.

Quick summary of preliminary results:

  • Mowing sumac in June and August really reduced both the height and density of stems, and that impact has persisted for at least 2 years.
  • An August mowing, followed by a dormant season fire (November, in our case), showed pretty similar results.
  • June mowing followed by herbicide in August seemed slightly less effective than the above two treatments, but much better than any single treatment alone.
  • June mowing followed by a November fire was the least effective of all the combinations listed so far, but still better than a single mowing treatment.
  • All single treatment applications (June mowing, August mowing, November fire) showed quick recovery within two years.
June 16, 2025 Photo of smooth sumac that received no treatment in 2023. You can just barely see my spade in the center of the photo, with sumac looming well above it.
This patch received a single prescribed fire treatment in November of 2023. If you look really closely, you can see just the handle of my spade. The sumac rebounded very well. This is similar to what both single mowing treatments (June and August) looked like by June 2025.

Treatments were applied on June 13, August 9, and November 29, 2023. The photos below show sumac patches with various treatment combinations.

This patch was mowed in June and August of 2023 and experienced a significant decrease in both height and density of stems (the slope in the background was untreated).
August mowing followed by November fire also had a significant impact.
June mowing followed by a November fire was better than any single treatment, but not nearly as effective as the other combinations.

The herbicide we used contained the active ingredient Carfentrazone-ethyl, which disrupts cell membranes in leaves and essentially defoliates plants. The hope was that it would act much like a prescribed fire – injuring the shrubs without killing them or any surrounding plants. We mixed 17.5 ml (0.7 ml/gal) of AIM herbicide and 47.5 oz (1.9 oz/gal) of crop oil in 25 gallons of water and applied a heavy foliar spray.

We tested this on full-sized sumac plants in June, but the spray didn’t penetrate the canopy well, and only burned up the top layer of leaves. It seemed to work much better in August as a follow-up treatment to resprouted sumac plants mowed in June.

The brown-leaved sumac plants on the right were mowed in June and the regrowth was sprayed with AIM herbicide in August. This photo was taken 1 week after spraying.

As we’d hoped, we saw no mortality of sumac or any other plants from the herbicide treatment. Instead, it seemed to act much like a prescribed fire, in that it just injured the shrubs. We’d expected it to do some temporary damage to surrounding vegetation as well, but saw very little evidence of that.

Here is the June 2025 photo of the sumac sprayed with AIM herbicide in June 2023. Height and density are both much reduced compared to untreated patches.

My takeaway from the herbicide application was that it is worth more testing, but seems less effective than mowing or fire. In places/situations where spraying might be feasible, but mowing isn’t, it might be a decent follow-up treatment to extend the impacts of prescribed fire. Maybe. We’ll see. Either way, it didn’t seem to cause any damage to the plant community around the sumac, which reinforces my interest in more experimentation.

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Field Trial #2 – Rough-Leaved Dogwood at The Nature Conservancy’s Platte River Prairies

For a few years now, I’ve been paying attention to fenceline differences and other evidence that cattle grazing has potential to help manage deciduous shrub height and density. This spring (2024) we set up a quick experiment to test that with rough-leaved dogwood. Cattle were brought into the unit in early June and will be present through October (part of our larger open gate grazing experiment.)

A fenceline photo showing grazed prairie on the left and ungrazed on the right. Note the height and density of the dogwood and plum on the ungrazed side.

Forty cow/calf pairs were introduced to a 49 acre pasture in late May, 2025. In early July, they were given another 25 acres (in addition to the initial 49) and later this summer, they’ll gain access to an additional 69 acres. The photos below, though, were all taken on June 10 – about 2 weeks after cattle were brought into the pasture. In other words, the grazing impacts shown below happened pretty quickly after cattle were brought in. It’s not like they waited to graze dogwood leaves until they’d eaten everything else.

We set up four treatments:

  • Grazed (unmowed)
  • Ungrazed (unmowed)
  • Mowed/Grazed
  • Mowed/Ungrazed

The height of all dogwood stems included in the study was measured on April 22, 2025 and some of those stems were mowed immediately afterward. Small exclosures were set up to exclude grazing from some treatments.

Quick summary of preliminary results (as of June 16, 2025):

  • Cattle are definitely grazing the leaves of dogwood. Stems outside the exclosures looked very ragged compared to ungrazed plants.
  • Dogwood stems mowed in April were being kept cropped off at just a few inches in height.
  • Dogwood stems mowed in April but excluded from grazing had already reached about 10-12 inches in height by June 16.
Grazed dogwood (left) and ungrazed dogwood (right, in the exclosure).
Dogwood stems inside the triangle of red flags were mowed in late April and cattle are keeping them grazed off close to the ground.
Dogwood mowed in April but excluded from grazing had grown 10-12 inches by June 16.

This project is just getting started, but it’s gratifying to see that cattle are grazing dogwood as we’d expected (see photos below for further confirmation). The most promising result so far is that the mowed dogwoods seem particularly attractive to cattle and we hope repeated grazing of those resprouting stems will lead to several years of much-reduced growth compared to stems in the other treatments. Time will tell, but we’re off to a good start.

My real hope is that we can find ways that cattle grazing can play into our larger efforts to manage shrub height and density. For example, burning every 4-5 years isn’t enough on its own to suppress shrub growth. However, burning followed by a season of grazing on the regrowth of those shrubs might lead to significantly reduced growth over the next several years. By the time the next fire comes through, those shrubs might not have grown very tall at all.

We have lots of experience (and data) showing that some kinds of cattle grazing can benefit habitat heterogeneity without reducing plant diversity. If similar grazing approaches can also suppress the height and density of shrubs, that’ll be a huge help.

This (including the sumac work above) is just the start of a long experimental path, but I’m excited by the early results.

A cow grazing dogwood on July 2, 2025
Even the calves are working on the dogwood.

I’m sharing these very early results in the hope that I can encourage others to do similar experimentation. Please don’t interpret these preliminary findings as anything more than what they are. We’re seeing some hopeful signs, but need to follow these trials for more years to see the longer-term impacts of what we’re trying. We also need to greatly expand the treatments and combinations to really understand what various options can do.

Please help! If you are a land manager in the Central U.S. and have shrubs in your grassland, it would be terrific if you could test these or similar approaches to managing shrub height and density and report back. Just as importantly, we need researchers to help us learn about the impacts of different degrees of shrub height and density on plant communities, pollinators and other invertebrates, birds, mammals, and much more. That information will be crucial to land management and help tell us what to aim for.

As I said in the first post, the increase in woody plants in our grasslands doesn’t have to be a catastrophe. It might just be one more factor we need to include in the way we think about managing prairies for various objectives. If we ignore the issue until the shrubs have filled in and taken over, though, we’ll definitely lose. Let’s not lose, ok?