Rachel: Welcome to Bug Banter with the Xerces Society where we explore the world of invertebrates and discover how to help these extraordinary animals. If you want to support our work go to xerces.org/give.

Matthew: I'm Matthew Shepherd in Portland, Oregon.

Rachel: And I'm Rachel Dunham in Missoula, Montana.

Matthew: So, you might have guessed from my accent, but I come from Britain. It's a country known for its hedgerows. I grew up surrounded by hedges, sometimes many centuries old, crisscrossing the countryside. Early in my career I helped plant, maintain, and restore miles of hedgerows and got to see up close the wealth of wildlife that live in them. When I moved to America, I was struck by the lack of hedgerows, their place in the landscape frequently filled by barbed wire or other types of fencing. I’m very happy to know that this is changing and there is a movement in this country toward planting hedgerows for their beauty, wildlife value, and economic benefits.

Matthew: Sitting down with us today is someone who has been at the forefront of this effort for a decade and a half. Jessa Kay Cruz is a senior pollinator conservation specialist for the Xerces Society in a region covering California and the Intermountain West. Since joining Xerces in 2008, Jessa has worked in agricultural and natural lands to create habitat for pollinators and other beneficial insects, and to promote practices that support them. She provides education and technical support to a range of individuals and agencies, including farmers and ranchers, agricultural professionals, and land managers.

Matthew: Welcome to Bug Banter, Jessa!

Jessa: Thank you for having me.

Rachel: We're very excited to have you on Bug Banter. We've both been looking forward to this. So, to begin, can you explain what a hedgerow is and why are they beneficial?

Jessa: Sure. I think there are probably a lot of different definitions for a hedgerow floating around out there. Sort of loosely defined, I would say a hedgerow is a linear planting of shrubs, maybe bunch grasses and forbs, or perennial plants. As Matthew alluded to, hedgerows have a really long, ancient history, but I would also say with some significant sort of modern adaptations. Hedgerows really started as living fences to delineate borders or boundaries, and also to support wildlife. And I think that wildlife support is something that people have really leaned into, sort of with our more modern hedgerows. So that's a really big piece of why people are planting hedgerows. And obviously they can be extremely beneficial for supporting wildlife, but hedgerows have a lot of other benefits, too. They sequester carbon, which helps reduce, you know, the impacts of climate change. They improve air quality, soil fertility, they help prevent erosion and runoff. So, you know, there's just so many different ways that that hedgerows are ecologically sort of beneficial. Obviously, my work really focuses on hedgerows to support pollinators and other beneficial insects, which I'm sure we'll talk more about throughout this conversation.

Rachel: Yeah. So you mentioned a few benefits. What are the features of a hedgerow that create those benefits? Help with combating climate change, and soil health, and providing for pollinators?

Jessa: Yeah, I mean, I think—. Hedgerows, in their design, are—can be—have complex designs that include a lot of different plants, and a lot of different—you know, with different structure from larger shrubs to smaller plants. And so what you're really creating is really like a tiny little ecosystem in and of itself. That's how I like to think of hedgerows. And so within that ecosystem, you have, you know, plant roots that are helping break up soil and improve water infiltration, for example. You have—. Obviously anytime there's living plants, they're taking carbon out of the air and fixing it into the soil, which helps sequester carbon and reduce the impacts of climate change. And then, of course, the plants themselves provide resources, structure for wildlife, food for wildlife. And the better the design of a hedgerow, the more benefit you can get out of planting it.

Matthew: Hedgerows are wonderful. You've done a lot of work with planting, developing, managing hedgerows in agricultural landscapes. Are these areas where pollinator hedgerows are most helpful?

Jessa: You know, hedgerows across all landscapes will benefit pollinators. I think agricultural landscapes are really uniquely important in our modern times for a variety of reasons. I think one is just that our—in a lot of areas, our modern agricultural landscapes are really devoid of habitat. You know, we have these very intense sort of fence post to fence post farming that doesn't leave a lot of space for wildlife, or for habitat. And so by creating these hedgerows—which don't take up a lot of space. Like it's very feasible to plant hedgerows in intensively farmed landscapes—and by doing that, you're changing this landscape from something that doesn't really support pollinators or wildlife to something that really does. And because we have so many acres of land throughout the United States, but especially here in California, in the Central Valley where I work, you know, so much of our land is under agricultural production, there's just huge—you can have really significant benefits with just planting small amounts of habitat.

Jessa: The other piece of it is that I also see agricultural hedgerows sort of as a win-win. So when you're planting hedgerows in these landscapes, not only are you potentially supporting all of these, you know, declining pollinators, but there's real benefits to the farm. Nearby farms can benefit from having increased pollination to their crops because of the pollinators that are being supported in their hedgerows. And they can also provide increased pest control through all of the different beneficial insects that also are supported by hedgerows. So I kind of think it as a win-win both for agriculture and for wildlife.

Matthew: I've also heard it said that the hedgerow provides shade in the hot climate for the field workers, too, when they're resting.

Jessa: A significant factor there because, yeah, for the people who live and work in these landscapes, it's a really harsh environment. There's—you know, it's hot, the sun is intense. We get really strong winds, and again, there's not a lot of sort of greenspaces. So yeah, just having a hedgerow on a farm can really transform the environment for the people who live and work there.

Matthew: And what kind of places on a farm would be appropriate for planting a hedgerow?

Jessa: Yeah. That's something I've thought a lot about. I would say, one of the most important things is an area that's easily accessible because, just like anything else, hedgerows need to be, you know, maintained over time. So you wanna put it somewhere that you can get to to do those management activities to keep your hedgerow healthy. Definitely wanna be thinking about protecting that hedgerow from potential pesticide—any adjacent pesticide use. So that's extremely important. And just protecting from other disturbance that might happen in an agricultural area. So, you know, accessible, protected. And then here in California in particular, does need to be in an area that you can do some irrigation. We choose plants that are very drought tolerant. Hedgerows don't need a lot of water, but they do need a little supplemental irrigation to get going. We have temperatures here in the Central Valley well up into the hundreds all summer long. These plans need a little bit of, a little bit of a drink to get established well.

Matthew: Yeah, definitely. So from that I'm guessing that like track sides, field edges, ditch sides, creeks, riparian, roadsides. There are so many places where you could bring a hedgerow in.

Jessa: Yeah. And those are the areas on a farm that we typically will look at. We'll look at areas along the edge of access roads. Sometimes equipment yard areas. Any riparian area in that landscape, that's always a key spot. So yeah, those little corners and edges of farms is typically where we're looking at to create our hedgerows.

Matthew: And if you were going in and advising a farmer on planting a hedgerow, do you like have a, like a standard hedgerow design? Or do you adapt it to the different area of the farm?

Jessa: It's a little bit of both. So we do kind of have this standard template and that's usually where we start. But we are always gonna be customizing that standard template to meet the needs, limitations, or goals of a particular farm. You know, so for example, somebody might say, “Well, we don't want anything too tall here because we don't want a shade adjacent crop.” So, in those hedgerows, I would maybe not include really tall shrubs. Conversely, sometimes people say, “Oh, we want this hedgerow to also be like a privacy screen.” And in those hedgerows maybe I'll put in more taller plants, or plant things a little closer together. So, you know, we start with this sort of template and then we customize what works in the particular landscape.

Matthew: And you mentioned earlier about planting a hedgerow in an area where there's like pesticides is not so good. But I imagine, as well, a hedgerow could be in the right place. It could be a barrier to pesticides, could it?

Jessa: That's an interesting question. And we do get a lot of people who sometimes want to do both. And a pollinator hedgerow is not a good fit for that. So if you have concerns, say about pesticide drift from your neighbors, you can plant a living screen that will really help block that drift, but that's not the place to create habitat. You would want to be planting, instead, plants that are actually not very attractive to wildlife if you know that pesticide drift is a problem. So that would be like a different type of hedgerow. We typically will call that like a pesticide drift barrier, or sometimes people just call them wind breaks. And yeah, people sometimes wanna combine those two things, but they don't go hand in hand. So a pollinator hedgerow would be best planted in an area where you don't have concerns about drift, and where you're not trying to have your hedgerow catch drift, if that makes sense.

Matthew: Yeah, totally. Yeah. You don't want it to be a trap.

Jessa: Exactly.

Matthew: Yeah. Hedgerows are like, what you've already said, they're really compact. You can bring a lot of benefit into a small area. So it seems like they, that they have uses and there’s a place for them beyond farms. Have you worked on hedgerows in non-farm locations?

Jessa: Oh, I have. Yeah, I've worked on hedgerows in almost any landscape you can imagine. I mean, solar farms, urban gardens, parks—there's really almost nowhere that a hedgerow wouldn't provide benefits, right? We all eat the crops that pollinators help produce, so no matter where we're supporting pollinators, it's something we wanna do. We all breathe the air, and drink the water, and honestly, hedgerows really help protect those resources through some of the things that I talked about earlier. So we all benefit from carbon sequestration. And honestly, pollinators across all landscapes, they really need all the help that we can give them.

Matthew: I was thinking about a hedgerow that I helped plant many years ago in Britain where there was a kids' playground, and then a country road. And so we actually put a really thorny hedgerow between the two to stop the kids running out onto the road, so. Haha.  

Jessa: That'll do it. And people have planned hedgerows for that purposes, you know, so then they want us to plant things that are thorny or unfriendly. Poison oak here in California is a native plant with very high wildlife value. It's not a common plant to put in a hedgerow, but if you wanna create a barrier, that's a pretty effective way to do it. Haha.

Matthew: Yeah. Assuming people know its poison oak, right? Haha.

Jessa: Yeah, assuming people know, otherwise you're gonna have some problems, but yeah. Haha. I think most people who live here, we know what poison oak looks like. Because it only takes one mistake and yeah, one bad case of poison oak and you're gonna memorize that plant pretty quick. Haha.

Matthew: Your work is in California. You mentioned Central Valley, Intermountain West. Hedgerows can be planted anywhere. I imagine any region there would be a hedgerow mix that would be suitable?

Jessa: Oh, absolutely. I mean, hedgerows are not just national, they're international. We started this conversation right, you talking about Britain, you know, the ancient history. I happened to be doing a trek in Portugal last summer through some agricultural areas, and there were hedgerows there, too, you know, along the wine grapes and corn fields and, you know, some of the other orchards. So it is definitely an international, universal kind of thing.

Rachel: Earlier you described hedgerows as kind of this mini ecosystem, which I really love. And as I was drafting these questions, I was thinking the same thing, like, “Oh, I wanna learn about these little ecosystems that we often don't really think about as ecosystems.” But what types of pollinators or other insects can you find in a hedgerow?

Jessa: So many fun insects. And in fact, a lot of our work has been, you know, doing a lot of follow up monitoring to see what types of insects our hedgerows are attracting, to make sure that we're really—they're really serving the function that we want them to serve. And I will say, from having done a lot of that monitoring, they definitely are. I see bees of all types in hedgerows—bumble bees, sweat bees, honey bees. We also see tons of beneficial insects. So these will be like natural enemies of crop pests, or insects that like hunt and kill crop pests. So things like lacewings, lady beetles, parasitic wasps, predatory beetles—just so many beneficial insects. And then of course, butterflies. Another sort of distinct group of pollinators that we see showing up and using these hedgerows, too, so. And that—and then those are just the pollinators and the insects, because that's what we're focused on. But, you know, there's birds—another huge group of wildlife that use hedgerows and that show up, and are really fun to see. And unfortunately, I'm really ignorant about birds, so I'm not sure what I'm looking at, but they're there. There's a lot of them.

Rachel: I love that. So you just mentioned that you're typically out there doing follow-up, which is the perfect segue to my next question. Do you have kind of a favorite insect that you like to see when you're out there?

Jessa: People ask me this question all the time, and it's so hard to pick a favorite. I'm sort of like a mom who can't have a favorite child, like a pollinator person who can't pick a favorite pollinator. But I will say I absolutely love our green sweat bees, or Agapostemons, here in California. They are just this gorgeous iridescent green. And when you see the sun just like glinting off of them, it's just such a beautiful sight. I mean, they're just a stunning color. They look like little jewels. So that really makes my day. The other thing that I really love to see—there's a type of bee called a longhorn bee, and they're named that because they have really long antenna. And the male longhorn bees typically, or often, sleep in flowers at night. So the other really cool thing to see if you're out early in the morning when the flowers start opening up is you'll see the little male—and usually there's several of them, all the little male longhorn bees all like clustered together, like sleeping in this flower. And it's just about—with their really long antenna—it's just the cutest thing in the world. So I love that, too. So those are a few of my favorites, but again, I'm a good mom, so I'm not gonna pick a favorite favorite.

Matthew: Of course, when you said that, “A few of my favorite,” I started thinking of Sound of Music there. But I'm not gonna burst into song, don't worry.

Jessa: Oh, good. I'm not either. Haha.

Matthew: Haha. Earlier you mentioned some of the other benefits—we've been talking about pollinators because that's sort of the starting point for Xerces and hedgerows—but there are all these other benefits. You mentioned carbon sequestration. I mean, it seems weird that we're now talking about how a hedgerow can save the world, but I'd like to explore a little bit more about what some of these benefits are. Do you have a way of measuring the carbon sequestration? I mean, is there any work that's been done to try and estimate the benefits like that?

Jessa: I believe that there is some work being done, and I actually think that some of our coworkers here at Xerces are doing a project where they're trying to look at different ways to actually quantify that—to measure the amount of carbon that is potentially being sequestered by planting hedgerows. And I think a hedgerow is particularly effective at sequestering carbon because of the diversity of plants in a well-designed hedgerow. So you've got larger shrubs, you've also got bunch grasses—these are permanent plantings, right? So these plants are gonna be there for a very long time. So I don’t know off the top of my head where—. I know that study is still ongoing. I know there's been other studies and publications of other groups really trying to look at that, trying to quantify benefits.

Jessa: And the same thing for some of these other benefits like soil health, or water quality—because they're basically helping sort of filter the water as it moves through the soil. They're improving the soil—just anytime you have living roots in the soil, you're improving the soil in this variety of different ways. Breaking up clay soil, initiating soil microbes, things like that. So, there's—there are studies out there looking at these other benefits and trying to quantify them. I don't have that data on the top of my head, but it is significant. The same way that we have this really solid data on yes, if you plant a pollinator hedgerow, these pollinators will show up and start using it, you know? Because that's the monitoring that I'm doing. We have similar data looking at some of these other benefits.

Jessa: And then the one thing also that I think you cannot quantify, and you hit on this earlier Matthew, but is the creation of these beautiful greenspaces. Very often in areas where people don't have a lot of access to greenspace, that's not something that can be quantified easily, right? The benefits to people of just enjoying it. But I would say, if you have ever just stepped outside on a summer day and sat down beneath the tree for a minute to catch your breath, close your eyes, feel the breeze, listen to the birds. There is something that happens in that setting that is really, truly magical, and sometimes transformative for people. And that's not something that can be measured, but I absolutely believe that it's just as valid as all these other sort of scientific factors that we look at. Yeah.

Matthew: There have been studies now which have begun to quantify some of those benefits of how time spent in nature, time spent with greenspace, time spent, like you say, sitting under a tree, feeling that breeze—it's so beneficial for our mental state.

Jessa: I think people really started to realize that more during the pandemic when we couldn't access a lot of the other sort of things that we did for recreation and enjoyment. Like so many people turned to the outdoors because that was one of the only sort of safe recreational spaces left, at least temporarily, in places where we could still sort of safely come together. And so I feel like there was a really renewed recognition of the value to human, physical and mental health that's created by having greenspaces.

Matthew: As you say, there's these unquantifiable benefits that hedgerows can bring wherever they're planted.

Rachel: So if someone was interested in planting a hedgerow on their property—we've talked, obviously, a lot about agricultural landscapes, but let's take someone that's more of in an urban habitat—if they wanted to put in a hedgerow, either along their fence line or instead of a fence, what would you say is their first step to get started?

Jessa: I would say treat it like, treat planting a hedgerow the same way you would treat planting like a new crop or planting a new garden. Which is to say, you know, start small, plan ahead, think through it, access resources. There's a ton of information for people who are interested in doing this work. So, you know, like have a plan and just start doing it little by little.

Rachel: Do you have any specific resources that you can guide people to?

Jessa: Here at Xerces we have a ton of resources for how to plant a hedgerow. Plant lists—which are really important because a hedgerow is really only as good as the plants that are in it. So really thinking about plant selection is super important. Are you planting things that are native, are adapted to your area? Are, you know, the right plants for your conditions in terms of soil type, or the amount of sun that you're getting, or the amount of water you can get them? Then, of course, doing a lot of sort of preparation, which kind of goes back to me saying like, “Treat this like a crop,” right? You wouldn't just plant something in the ground without doing a little prep first. So, you know, clear those weeds out of the way, install some drip irrigation, make sure you've got everything kind of set up and ready to go.

Jessa: It's not hard, you know, these plants aren't difficult to grow. But you also can't just throw things in the ground and forget about them either, right? So there's a happy medium. So yeah, Xerces has a ton of resources. And then there's a lot of local agencies like the Natural Resources Conservation Service which is geared toward doing this kind of work in working lands. There's also what we call here in California, Resource Conservation Districts, or in other areas they call them Soil and Water Conservation Districts. So these are—both these districts I'm describing are both types of government agencies that again, are there to support people who want to do this type of work. They provide technical assistance, in some cases, financial assistance. So there's, yeah, there's a lot of resources out there.

Rachel: And then once these are planted, in terms of management, are there methods or techniques that are better than others?

Jessa: Not necessarily. I think this is one where it really depends on the tools available, and the landscape, and the scope. So, I would say generally speaking, weed management and irrigation are the most important things. Because getting rid of weeds reduces competition and that's often a huge issue. And then making sure you're giving the right amount of irrigation, not too much or not too little, just like a crop. So I think the specific methods, again, depend on what resources somebody has. Sometimes people get in there and hand weed or use weed whackers. I've seen people use chickens and ducks, and things to go in and pull out some of the smaller weeds. There's a lot of different methods. And again, I think it just depends on who you are, and what tools you have available.

Matthew: When I was young in Britain and with the hedgerows there, once they were grown there was the hedge laying approach of taking your hedge plants and slicing partway through, and then bending them down so you could regenerate. And others would just get cut down periodically. So they were coppiced and then regrow. And then the endless debate over, if you're using a mechanical flail mower, what shape should you mow your hedge: flat topped, or angle sided, or what? You've been around hedgerows for a while now. Are you finding those kind of debates developing now as hedgerows have got bigger? People are like, “Ooh, should it be tidy? Should it not be tidy?”

Jessa: Yeah, a little bit, but not as much as I maybe would have expected considering sort of the history of what you're talking about. I think that it maybe is a cultural thing. But at least here in California, these hedgerows are designed with native plants. Native plants are by nature, not tidy. Haha. But the expectation isn't for that either. And I do—when I'm talking to people about hedgerows, right from the start I do try to emphasize that, or show some photographs of what a mature hedgerow looks like, because it's not a nice, neat, tidy, little, squared-off hedge. And I think sometimes people hear “hedge”—the “hedge” in hedgerow—and they are expecting something like that. This is not that kind of hedgerow. Our pollinator native plant hedgerows are—they're wild looking. It's a little slice of nature. So sometimes the plants get a little sprawly, or leggy, or corded into each other, and that's okay. To me, it's all about: are your plants healthy? Are they thriving? If you wanna shape it, if you want it to look a little more formal, that's fine. You can prune it back, you can square it off. It's probably not gonna hurt anything. But you absolutely don't have to do that. And I do try to set that expectation. Like this is not like a—yeah, these aren't like a little box hedge or something. That's not what we're talking about here.

Matthew: It's a little rambunctious wildness, right?

Jessa: Yeah, rambunctious. That's a good word for it. It's gonna be a little bit rambunctious.

Matthew: Well, Jessa, thank you so much. This has been great. I'd say I'm a, I get excited about hedgerows, so to have this time just to sit around and talk about them, it's been great. And so we're coming to our last two kind of standard questions we have. So, one that we always love, and I find it fascinating the range of answers we get to this one, but what inspired you to pursue a career in insect conservation?

Jessa: So, I get asked this question a lot and my answer has changed over time. And I think what's changed is I keep going further and further back in my life. And I realized when it started was way, way back when I was a toddler. We were living in Boston, and [a] very urban environment, not a lot of access to greenspaces. I come from a family of avid gardeners all the way up the line, and my mom was no exception—she absolutely loved to garden. And she had a little plot in what's called the Victory Gardens in Boston. Which, I don't know how much people know about the Victory Gardens, but they were started toward the end of World War II to actually address food shortages in the United States. And these gardens—some of the very first sort of urban gardens in the country were these Victory Gardens that were started in Boston. So back when I was a kid, my mom had this little plot in these historic Victory Gardens because we lived in the neighborhood. And she would bring my sister and I there to play in the dirt while we gardened. And apparently, I was at my happiest when my mom would just plop me down in the dirt in my diapers and let me just go for it. And so there's photographs of me digging in the dirt and playing with worms. And honestly, I think that really is where it started because I am still at my happiest sitting in the dirt playing with bugs. Haha. So here I am.

Matthew: Oh, that's great. I mean, the—Boston's Victory Gardens are pretty famous. So yeah, what a nice start.

Jessa: Yeah, at least we have my mom to thank for that, and my grandpa before her. And like I said, so on up the line, so. Haha. It's in my genes.

Rachel: Or your diapers.

Jessa: Yeah, the diapers.

Rachel: Haha. Sorry. I was like, “That was probably a bad joke.”

Jessa: Haha.

Rachel: The last question we have: if you could see—and this might be difficult. It is hard for some people—but if you could see any bug in the wild—and the wild being anything outside of captivity—what would it be?

Jessa: This is a hard one, too, right? Because there's so many cool insects out there. But once again, with this question, I go back to my childhood. Very—I'm very nostalgic for fireflies, because I grew up on the East Coast and I have a lot of family in the Ohio River Valley where there's tons of fireflies. And so that was a big part of my childhood. Which we don't really get to enjoy here in California. There's not very many species of fireflies, and the ones that we do have, most of them don't light up, so they're not quite as sort of magical. But I do have this, you know, like I said, this nostalgia about fireflies. And I was reading recently about, I believe they're called blue ghost fireflies that can be found in North Carolina, which I've never seen, but apparently, they give off this kind of like otherworldly blue glow. And it just sounds so amazing to me. So on my bucket list is to go to North Carolina and see these, these cool, blue ghost fireflies.

Rachel: Oh, that's a good answer. Definitely creates this scene in my mind of these like light blue just going off in the forest, and yeah, they are quite magical.

Rachel: Well, thank you so much, Jessa. It's been great to get to know you a little bit more, and hear more about the work that you do. Xerces has grown so much since I started, it's hard to keep track of folks. But you've been at Xerces for so long, I feel like you're this staple. And to just know what you're doing, and what you're up to, and learn more about hedgerows. I don't, admittedly, know as much about them. But I can say I know more now—Haha—having talked with you in this interview.

Jessa: Oh, well that's great. Thank you so much, Rachel. And yeah, like, I'm obviously really passionate about hedgerows, and the work that I do just builds off on the work that lots of other amazing people have done. So I'm just really grateful to be able to be doing this work. I've been doing it for a long time, and I hope to continue to do it for a long time to come.

Rachel: Well, thank you again so much for joining us.

Matthew: Bug Banter is brought to you by the Xerces Society, a donor-supported nonprofit that is working to protect insects and other invertebrates—the life that sustains us.

Matthew: If you’re already a donor, thank you so much. If you want to support our work go to xerces.org/donate. For information about this podcast and for show notes go to xerces.org/bugbanter.