Public Enemy

by | Jan 28, 2018 | Native Plants

Love-hate relationships. We have them with plenty of things: technology, holidays, even doughnuts. Then there are things we simply hate: traffic, mosquitoes, wet socks — and, sometimes, native plants. In Central Texas, many consider public enemy number one to be a native Texas tree, none other than Ashe juniper (Juniperus ashei), commonly known (and derided) as “cedar.”

Sure, you might also hate thistles or prickly pears or have a vendetta against a particular “weed” or some quickly reproducing, rhizomatous shrub. But none of these slightly annoying plants warrants a successful tell-us-why-you- hate-it-in-five-words Twitter campaign like the Austin American-Statesman’s cedar hate-fest from 2016, which elicited such responses as: “Sucking my will to live,” “I hate you so hard,” and “They’re trying to kill us!!!”

To be fair, this Twitter onslaught was directed at cedar fever, the allergy plague that temporarily ruins people’s lives every winter thanks to the abundance of Ashe juniper trees in Central Texas and their correspondingly abundant pollen.


Haters Gonna Hate

Robert Cook, M.D., of Central Texas Allergy and Asthma Center says the allergen in cedar is “very, very potent and it’s very prevalent; there’s a ton of it.” Compared to related species such as eastern red cedar (Juniperus virginiana), he says Ashe juniper (what, in this story, we always mean by “cedar”) “more rapidly releases its allergen from the pollen.” Most Central Texans, in his experience, have a honeymoon period of one to six years before they “pick up” an allergy to cedar. “The problem with the allergic immune system is that it misidentifies cedar [and other] allergens as parasites,” says Cook. Our bodies then feel the need to defend themselves. That defense comes in the form of snot, tears, coughing, sneezing — all the hallmarks of sickness (except, Cook points out, actual fevers).

For many, it is an annually recurring problem that is expensive and exhausting and infuriating all at once. It’s a problem with an emotional response. Elizabeth McGreevy, an ecological landscape planner who’s been working with and observing Ashe juniper for going on 20 years, says emotion is at the heart of our cedar misconceptions. In essence, we are unable to think rationally about cedar (also known as “mountain cedar”) because we already feel so much about it. “There is such a strong momentum” toward the negative, she says — hence the popularity of the Statesman’s “#CedarFeverIn5Words” idea.

“Never in my life have I come across a more determined group of people than those hell-bent on the annihilation of a single species of tree,” writes McGreevy in her forthcoming book, “Mountain Cedar: Wanted Dead and Alive.” During talks on cedar (in which she defends it), she says people have literally thrown their lunches at her.

Writer John Graves called cedar “unblessed” in his ode to the Brazos, “Goodbye to a River.” And the Wildflower Center’s own Native Plant Information Network describes it as “often hated and targeted for removal,” attributing the situation to allergies and “various, sometimes invented rationalizations.”

These “rationalizations” are what McGreevy, a third-generation Texan, collectively refers to as “the bandwagon.” When it comes to cedar, the consensus is vehemence. It’s a hate band- wagon based largely on speculation and the proliferation of rumors, and she says everyone is on it.

Feeling crumby for months at a time will make anyone cranky, and just about everyone agrees that cedar fever is the primary cause for the public’s general disdain of Ashe juniper. But passengers in the bandwagon aren’t just allergy sufferers. They are people who believe a variety of cedar myths: that they’re not native, that they’re highly invasive (“unchecked” is perhaps more apt), that they will make your land infertile and soak up every last drop of rainwater.


Persistent Myths

McGreevy is trying to dispel some of these myths with her book. She points out cedars are actually viewed as “precious and rare” in other regions where their populations are isolated and unique, listing the Arbuckle Mountains of Oklahoma and the Ozark Mountains of Arkansas as places that revere cedar and even bestow special names upon their cedar populations. Her goal is to provide people with “a better understanding of why and how this veteran of our Hill Country has become invasive and why it deserves some respect.”

“Cedar is a part of this ecosystem,” she writes. “Balance is what we need,” which includes “a balanced view of the cedar.” That means getting to know cedar, warts and all. It means understanding the difference between old growth and new growth, learning how to manage cedar-dominated lands for best results, and accepting the truth that some cedar trees should be left alone, whether we like it or not.

Likewise, Wildflower Center Ecologist and Land Steward Michelle Bertelsen says cedar is “a very important species; a lot of other species depend on it.” Among that list are Texas madrone (Arbutus xalapensis), gum bumelia (Sideroxylon lanuginosum), possumhaw (Ilex decidua) and Texas red oak (Quercus buckleyi), to name a few. McGreevy says these species “often cannot get a start anywhere else but within the protective branches of our cedars.”

Cedar sage (Salvia roemeriana), cedar sedge (Carex planostachys) and cedar rosette grass (Dichanthelium pedicellatum) are three native plants that occur almost exclusively in association with cedar — hence their names; both take advantage of the rich, well-draining soil that builds up under decomposing juniper leaves. (That’s a far cry from the common misconception that cedar makes land infertile.)

However, Norma Fowler, Ph.D., who researches plant population biology and plant ecology at The University of Texas at Austin, says these associations could have to do with protection from deer as much as anything; data on the relationship between cedar and bracted twistflower (Streptanthus bracteatus), for instance, supports this claim. She also notes that, because cedar is so ubiquitous, many native woodland species occur in association with it by mere circumstance.

In addition to enriching soil and nursing a variety of complementary native plants, cedars — particularly old growth cedars — provide habitat for the endangered golden-cheeked warbler (Setophaga chrysoparia), whose nests are built almost entirely out of the shaggy bark of mature cedar trees. Cedars are also larval host to juniper hairstreak butterflies (Callophrys gryneus) and make a mean fence post or telephone pole (according to the Williamson County Historical Commission, very large cedar trunks were once “used extensively” throughout Austin as telephone poles).


Golden-cheeked warblers rely on the bark of mature cedar trees to build their nests, one more reason to keep some of these much-maligned trees around. PHOTO Gil Eckrich

Golden-cheeked warblers rely on the bark of mature cedar trees to build their nests, one more reason to keep some of these much-maligned trees around. PHOTO Gil Eckrich


Cedar brakes can also help slow erosion and mitigate flash flooding along riverbanks. Wildflower Center ecologists, Fowler and others agree the fibrous roots of native grasses are best at this — in the short film “Selah: Water From Stone,” J. David Bamberger, founder of Bamberger Ranch Preserve, calls grass “the greatest conservation tool ever made.” But, as Fowler points out, “any good plant cover is better than none at holding onto soil.” While she wouldn’t recommend planting cedar as a first choice to manage soil erosion, she also wouldn’t recommend cutting cedar on a slope or riverbank without some plan for preventing erosion until other plants become established.

Speaking of rivers, McGreevy says another myth is the idea that cedars were “only occasionally here and there inside of little canyons.” She argues that they were part of the once-diverse Hill Country landscape on both slopes and flat land. The Hill Country Land Trust agrees, writing the following in their “Managing Ashe Juniper” guidelines: “A survey of early 19th [century] European settlers and explorers’ accounts of what they saw upon arrival in the Hill Country describes an abundance of juniper, not only in the canyons, but also in dense thickets and both rolling and flat terrain.”

What about the claim that cedar is a water hog? “It does use water,” says Bertelsen, but “so does all of the other brush.” Land management, in her view, “is about the reduction of woody species or not; the individual species doesn’t matter that much.”

“They’re a native species behaving badly, but it’s not the species’ fault.”

So, besides that darn pollen, what’s the problem? The simple answer is that there is just too much cedar — especially young, shrubby cedar — in our landscapes. Some of it does have to go for healthy terrain to flourish, but McGreevy and Bertelsen both stress the need for informed, calculated decisions about cedar removal rather than cold-hearted annihilation.

“They’re a native species behaving badly,” says Bertelsen, “but it’s not the species’ fault. It’s bad land-management practices and the removal of [natural] fire that allowed that to happen.” Fowler points to the overpopulation of white-tailed deer — a problem caused, in part, by certain ranching practices, hunting restrictions and urbanization — as another factor; apparently, Odocoileus virginianus will happily snack on most woody species but generally pass on you-know-what.

Because there’s more cedar than anything else, Bertelsen says it’s a “low-hanging fruit.” But she adds that “oaks can be just as bad,” acknowledging the existence of an oak bias in our culture. “I have it too,” she admits. “It gets a pass when it sometimes behaves just like the cedar.”


Growing Pains

Bertelsen says the ideal thing is “for us to have a very patchy landscape,” including open grassland and open savannas, woody areas and woody slopes. That means “punching holes” in cedar-scapes and other woodland areas to make room for diversity. The idea is to recreate the “little disturbances” that would have occurred naturally — namely, fire and large-scale, nomadic grazing.

“I come at [cedar] from more of a range-management perspective,” she says, “I kind of lump it in with all of the other brush” — which she’s just as “happy to kill” as cedar for the right land-management reasons. But she also keeps a lot of cedar alive “in the right spot,” and old- growth cedar gets special allowance.

“The older stuff grew up under normal disturbance regime, so it tends to be a little more diverse,” says Bertelsen, meaning it’s naturally varied in size, placement and botanic company. The new ones grew up in this artificial no-disturbance regime, so you just get solid cedar and nothing else, so that’s less useful” from a biodiversity standpoint.

And guess who is to blame for that solid-cedar situation everyone despises? Not Mother Nature, not “evil” cedar itself, but eroded grasslands — once-healthy prairie that has been irreparably degraded by fire suppression, over-grazing, farming and settlement.

It’s a tale of man wearing earth out. “Once, before the Anglo-Saxons hit it, much of that lime- stone belt [in Hood and Somervell Counties, southwest of Fort Worth] was a rolling prairie thick in grass,” wrote Graves. “But its topsoil wasn’t deep and used away quickly under the bite of plows and herds.” Cedar then expanded as “the only feasible expression … of nature’s abhorrence of bare ground, until finally in some places, as far as you could see from the highest hilltops, there was only a green-black unreflecting expanse with a few ashes of white stone where even cedar couldn’t grow.” An unreflecting expanse of cedar similarly spread over degraded land in the Edwards Plateau. Graves put the cause more simply when he wrote, “Men increase; country suffers.” In short, it’s our fault.

Don’t feel too bad; that was before your time. And McGreevy places a little blame on American robins and jackrabbits, saying, “They’re the ones that spread the cedar into the grasslands. They won’t go in [a grassland] if the grass is healthy and thick; they like it to be sparse.”

So humans, it turns out, created an impoverished landscape ripe for woody species to grow in abundance and, in doing so, practically sent an invitation to seed-carrying birds and mammals. Whoops.


Nature’s Band-Aid

McGreevy agrees with all the support behind old growth cedar, but she is also the proponent of a much less popular argument: that young, shrubby cedars have something to offer.

She describes young cedar thickets as Band-Aids on the land. A bushy cedar thicket’s “only purpose,” says McGreevy, is to be “a mega soil-building machine. It’s not trying to get more water in the aquifer; it’s not trying to produce grass for a cow; it is nature’s wholehearted effort to restore the soil, to protect it so no more erosion happens.” Of course, cedar’s true objective (like that of all plants) is to reproduce — to create more cedars — but its soil-restoration side-benefit is nothing to sneeze at.

A common misconception is that these thickets are the worst type of cedar and should be immediately eradicated. But McGreevy says, if you have a little patience and give them a chance, they’ll become a “living plant nursery.” (Revered Texas naturalist Roy Bedicheck made similar claims about Central Texas trees serving as wildflower nurseries.)

In this scenario, she’s differentiating between shrubby cedar and treelike cedars and claiming, essentially, that one can help nurse the other. “Once a cedar is a shrub it never really becomes a tree,” she says, but eventually you’ll start seeing single-trunked “stick cedars” come up. McGreevy says people love to lop those off. As if play-interrupting a clear-cutting developer, she exclaims “No!” in exasperation. “Those are the ones you should be keeping!”

When you see those single-trunked cedars come up, she argues, the best tactic is to mulch down the bushy surrounding thicket and let the treelike cedars flourish. “Those are the ones that are going to become trees,” she says. (The words “trunk” and “treelike,” in this instance, must be envisioned on a small scale — basically, one must ask if a plant looks like it’s going to mature into a bush or a tree.) “Those [treelike] cedars grow up with the new canopy and form a forest,” McGreevy says. “That’s when it becomes diverse.”

If plants aren’t growing under cedar, McGreevy says it’s because that thicket is still acting as a soil-building machine. “There’s not enough soil; it’s still too alkaline; animals can’t get in there. You just go through and cut up some branches, next thing you know armadillos get in there, and you start see all these plants growing underneath.”

Feel the Burn

Prescribed burns are the Wildflower Center’s method of choice for fabricating a diverse landscape, one that Bertelsen describes as “actually the gentlest thing you can do.” Because cedar’s takeover is often so complete, the first round of “hole-punching,” in her terminology, usually has to be done mechanically using tree shears and chainsaws — or large, expensive machines that are potentially more damaging to soil and less specific in execution. In either case, that mechanically thinned landscape can then be maintained with fire.

“Fire, if it’s going through an area that’s already been thinned,” she says, “is going to be a much lighter touch. You’ll end up with that patchy environment, which is what we’re going for.” And fire will make choices for you. “It’ll kill that juniper or won’t kill that one; it’ll limb that one up and then kill this whole clump of them, but then that one over there got left,” explains Bertelsen. In this way, you end up with the age distribution and diverse structure that nature would have provided via fire and migrating herds of grazing animals.

An added bonus? Fire may actually help with that whole cedar fever problem. According to a recent study by Susanne Jochner-Oette, Ph.D., using data collected on Wildflower Center research plots, prescribed fire can decrease pollen concentrations at a local scale.* “Two years ago we turned our volunteer room into a makeshift lab and Wildflower Center volunteers contributed almost 200 hours collecting pollen, entering data, preparing slides and counting pollen under microscopes,” says Center Manager of Volunteer Services Carrie McDonald.

The study found that pollen concentrations were, on average, 15 percent lower at burnt plots than at control plots, and pairs of adjacent plots revealed a pollen reduction of up to 50 percent. So there may be hope yet.


Save the Drama

Whether managing land with “hole-punching,” mechanical removal or fire (or some combination thereof), McGreevy and Bertelsen agree it’s time to check our cedar drama at the door and look at the bigger picture.

“It’s not black and white,” says Bertelsen. Some cedar should stay; some should go. Land  needs to be managed with consideration, not annihilation.

Which takes us back to McGreevy’s idea of balance. There is another school of thought — that you should never kill any tree ever for any reason. But that’s just another extreme, an end-of-the-spectrum, no-compromise view that similarly ignores subtleties. “We want everything to be cut and dry … black and white,” writes McGreevy. “But issues of ecology never are that simple.”

As with most things in nature, cedar is a gray matter. It’s part of an ecological system that is more complicated than unadulterated hate, more nuanced than a snotty Kleenex, more worthy of our consideration than it has been treated thus far. Haters are gonna hate, but you don’t have to. You can understand your environment, learn to coexist with it — even come to love something that has a lot to offer, whether it be warbler habitat or fence posts or a deeper understanding of Texas’ natural (and human) history.


*The study was published in Landscape and Urban Planning and coauthored by the Wildflower Center’s former director of research and consulting, the late Mark Simmons, Ph.D.; Johanna Jetschnia; and Dr. Annette Menzel.