Arctostaphylos patula: Greenleaf Manzanita – Seeing a Plant in Context

Arctostaphylos patula growing on site near Whychus Creek south of Sisters, OR.  Here it is 5' tall growing in a mixed condifer forest along with Doug Fir, Grand Fir, Noble Fir, Ponderosa Pine and Western Juniper.

Arctostaphylos patula growing on site near Whychus Creek south of Sisters, OR. Here it is 5′ tall growing in a mixed condifer forest along with Doug Fir, Grand Fir, Noble Fir, Ponderosa Pine and Western Juniper.

Outside our breakfast window, when I was a kid, was an Arctostaphylos patula. I never thought that much of it at the time, and how unusual it was, that sometime, probably by the late ‘40’s or early ‘50’s, somebody had dug one up and transplanted it to our yard in Redmond. They are denizens of the eastside Ponderosa Pine forest ecotone not the Sagebrush ecotone where I grew up. We averaged less then 10” of precipitation a year, too dry (For those who don’t know Redmond, OR, lies wholly within Oregon’s High Desert country that puts it in USDA zone 6b, -5 to 0 F). It grew in this little jog of the house facing northwest. I’m sure it got overspray from when we dragged hoses and sprinklers around to keep the lawn green, which is probably why it had grown with some vigor, having a form that you wouldn’t see in the Ponderosa – Juniper transition band sixteen to twenty miles away. In my memory it was always clean, with bright green foliage, part of which can be attributed to the low desert humidity and our sandy soil. I wish it was still there to take a picture, but the house has sold several times and had ‘improvements’ to the structure and the landscape including an irrigation system. I don’t know whether it rotted out or they removed it for one of their remodel projects. In its day it was 6’ high x 7’-8’ across with the characteristic sinewy branches and smooth peeling red bark.

Driving south of Bend on US 97 you start seeing it with the Ponderosa. Bend itself straddles the transition between the two ecotones. This is where average annual precipitation has hit the 14” generally thought to be the minimum for healthy Ponderosa Pine. Nineteen miles to the west of Redmond is Sisters and that transition line traces an irregular track to Bend and then north hugging the Cascade foothills. I think it was down toward Gilchrist, going up to Crescent Lake, where I’d go in summers to Scout Camp, where after fires or clear cutting, you would pass through broad acreages of Manzanita, over your head, at least in my distorted childhood memory, and nearly impenetrable. The branches are on the stiff side and when broken are ‘jagged’. These landscapes resist bush-wacking and timber folks have a strong aversion to them as it makes them all but impossible to plant in and inspect. Brush in general is a negative to foresters at least until the crop trees are tall enough to out compete it. In such company ‘brush’ is a pejorative. Manzanita, Snowbrush, Bitterbrush, Deerbrush, Rabbitbrush… though they are native to this part of the country and commonly colonize burned over lands yielding over time to the conifers, are thought by many to be woody weeds. When development has come to ‘town’, historically, these have been cleared without hesitation.

Four miles to the west of downtown Bend, is a development, well beyond the resources of everyone I know. Tetherow, lies between Century Drive (the highway to Mt. Bachelor and the high lakes country, and Skyline Drive that takes you to Tumalo Falls and the old ski area that predated Mt. Bachelor. It’s beautiful country and over the years has seen its share of clear-cuts and devastating fires, including the Bridge Creek Fire in 1979 that burned further west around Tumalo Falls and this summer’s Two Bulls Fire, that burned over 6,000 acres just north across Skyline Dr. from there. But it was the Awbery Hall Fire in 1990 that burned 3,400 acres including Tetherow.

Fire’s, when not strictly controlled for decades, tend to burn with lower intensity…but protecting the land, the timber and more lately, homes, from fire, allows the fuels to build up, and the fires burn with much greater intensity. Low intensity fires tend to thin the thick barked Ponderosa burning away smaller weaker trees and the brushy understory. Plants like A. patula have a lignotuber, think of it as an expanded woody main root, that is capable of initiating new growth should the above branching structure be burned away. Low intensity fires clear the ground for their speedy return. High intensity…burns everything. The returning brush layer, in these cases, is slowed as it is may be dependent on seed germination opening the way for more erosion on soils that have had their organic layers burned away. But return it does. Its seed requires scarification by fire. The Manzanita is an integral part of this ecosystem, because not only does it cover the ground quickly after a fire to protect it, but it is itself relatively flammable to assure that fire will occur with some frequency and thus maintain the health of the forest. We have broken this cycle. Now Tetherow is spotted with scattered stands of Ponderosa left where the fire was less intense, connected by much larger acreages of brush.

There’s a golf course sprawling across the middle of this landscape. Wide paved and curbed roads meander through, (please note all of the ‘no parking’ signs if you visit), forming loops with cul-de-sacs bordered by expensive homes, green lawns and ‘natural’ looking landscapes comprised of plants that never grew here. Sprinklers slowly trace their arcs wetting everything while near by sections are stripped and graded, being prepared for the next phase of building. I’m sure some of this is done to reduce fuels and create a more fire resistant landscape especially around the homes.

The mixed brush cover

The mixed brush cover

I stopped on the main loop road to take a closer look at the landscape that grew in naturally after the Awbrey Hall Fire. It’s a dense informal mosaic of low shrub cover, most of it less than 3’ high: Arctostaphylos patula, Purshia tridentata and Ceanothus velutinus predominately, with Rabbitbrush, now known as Ericameria nauseosa, growing more around the edges and near basalt outcroppings. They all flow one into the other. With their density, evergreen foliage and the accumulation of leaf litter beneath them not much else grows with them. They constitute a ‘complete’ community their roots reaching down various depths retaining and drawing nutrients back up that would otherwise leach away in the porous soils. The Ceanothus helps to further enrich the soil by ‘fixing’ nitrogen so there is a balance that is biased slightly to building and enriching the soil over the years, each plant playing its role. This is a harsh landscape that left alone will move back to the Ponderosa Pine forest that was once here, not just along the edges. Although it was burned, it is still intact.

Greenleaf Manzanita in fruit

Greenleaf Manzanita in fruit

Further south and west in Central Oregon, where the climate is increasingly wet, relatively speaking, all of these grow with more vigor, with the exception of the Ericameria which is more of a desert scablands resident where you would find it growing with Artemisia tridentata and Juniperus occidentalis, but here they overlap. So the Greenleaf Manzanita of my childhood, was an anomaly, growing in the High Desert. Without our ‘intervention’, although it was inadvertent, it likely would have died early on, but instead it responded to a little water with longer internodes and a more sinuous habit. I can assure you that this was not done through conscious effort by my parents.

The new landscape with mounds from grade work in the background

The new landscape with mounds from grade work in the background

I was here at Tetherow last year and so have noticed the advance of ‘progress’ across the site. I don’t know how much ‘rescuing’ of Manzanita is being conducted here or if its mostly being bulldozed and burned. It is clear, to anyone watching, that this uniquely balanced and attuned landscape is losing ground.

Manzanitas are edging up in their popularity for home landscapes in the West today, though I doubt if in Oregon at least, they are ever found in the big box stores (I don’t shop there, but maybe they do in California which is the center of diversity for the genus.) There are species available, well beyond the ubiquitous and over used groundcover Kinnickinnick, A. uva ursi, that can thrive across much of Oregon if you know where to look, and there are species, like A. patula, which is well attuned to much of the colder and drier east side of the state, that are few and harder to find. Propagation of this species is difficult and those who try have a very low success rate. If you’re in the nursery business to make a living, you have to question dedicating your time and resources to such a plant. When you find these for sale they are often rescued plants from developments such as Tetherow or dug by permit from public forest-lands. Places like Tetherow, are particularly sad to me, given my connection to the plant, its appropriateness to dry-side landscapes, it’s difficulty of propagation and the disregard it is commonly shown growing in situ. It is considered a fire hazard to many, one of the characteristics that has made it invaluable in the Ponderosa ecotone. We have stood the world on its head when the residents of a place to which a plant belongs now work to limit or even eliminate it.

Watering the xeric native landscape

Watering the xeric native landscape

Driving through Tetherow I was stunned when I came across a whole series of rotary irrigation heads blasting away along the curb, not watering lawns and their residential contrived landscapes, but a 25’ deep band of native plants growing back into established Ponderosa, the same plants that have been growing across the road happily on their own??? This can only be an attempt to make the landscape more fire resistant! And, it is true that almost any plant that is growing more lushly is such when compared to one more stressed by drought conditions. There is something wrong about regularly watering a native, xeric, landscape that is self-selected for exactly the existing conditions to make it more fire resistant. I’m not saying that the homes built out here are expendable should another fire begin (22 homes burned in the Awbrey Hall fire. Today, with so much more residential development in the area the numbers would be much higher.), but I guess I’m asking how much longer do we keep expanding and building, sacrificing native landscapes and habitat for our own goals and needs? The landscapes and wildlife are self-limiting while we as a population keep growing and modifying the landscape.

Landscapes like this one at Tetherow are transitional as I noted before, they represents a loss to us all, as its fragmentation and elimination continues. Ultimately, Tetherow will contain little islands of native landscape the developers choose to leave standing that will decline over time as they are too small to sustain themselves and new plant material slowly invades from the increasingly dominant contrived landscapes and the regional invasives like Knapweed, Cheatgrass and Chicory.

Driving in up from Century Drive my eye was drawn to the trees and shrubs that have been added in a mixed informal planting along the entry road, an attempt, I assume, to look natural. The Oaks, Mountain Ash, Plums and Ginnala Maple trees, most of the shrubs, even the native species, would never have been found anywhere near here and, on the cut and filled mineral soils in which they are forced to grow, they now and will continue to struggle, serving as a reminder, to those who pay attention, that they don’t belong and represent a lost opportunity to do something more appropriate to the site, beautiful, xeric and, ultimately, more sustainable.

[Please note that I’m discussing A. patula from a personal perspective. This is not a professional monograph. I am well aware that it naturally occurs in many different plant communities west of the Rockies each with its own characteristic members, but all of these communities share the same regional, mediterranean, summer dry, winter wet, climate. The particulars vary across a range, but tend to be on the drier side, and all Manzanita serve similar roles and functions, though the fire cycles of their particular community can be as frequent as annual to more than 80 years between events. Western North America is the center of genetic diversity for Conifers and many of them share space in some of these communities. Others are defined by shrubby evergreen Oaks, another by Quaking Aspen and still more by species that may surprise you. For an interesting read go to: www.fs.fed.us/database/feis/plants/shrub/arcpat/all.html. Wherever you live, make an effort to get out and see what used to grow there, or maybe it still is. Whether you grow bonsai, vegetables, a cottage garden or Vireya Rhododendron in a greenhouse, understanding where you live makes you both a better gardener and citizen.]

Some of you who know me will think I’m being inconsistent here, the guy who plants Palms, Bananas, mediterraneans and a wide array of southern hemisphere plants, but that is at home in Portland, in a landscape that has been severely compromised, with extremely disturbed soils, for decades. Please recall that I have also been working to find out what our new landscape can/should be, what ‘belongs’ given such a radically altered region. The local plant communities were destroyed long ago and the exotic plants, including populations of invasives, are well established in the landscape and seed bank. This is different. The cycles in places like Tetherow are still intact. I don’t expect my rant here to stop work there, but it would be nice if people started to examine our history and practice of ‘development’ and begin to attribute value to ‘under utilized’ native landscapes. In the mean time, ‘Viva la Arctostaphylos!

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