Some years ago, an arborist made a snag from one of our yard trees. Less than a decade has passed, but it is beginning to soften up, attracting he interest of some cavity-nesting birds. The nuthatch in this video spent several long days working on a couple of nest cavities, only to be run off by a northern flicker. After it made some test holes, the flicker decided it wasn’t the perfect place. Meanwhile, it is a favorite perch for the dawn chorus.

Equally interesting in the saga of this big snag, is the cascade of changes initiated by the sudden absence of a large tree. Resources – light is one of the most important – are limited in ecosystems. A large tree taking up air space and light has a big effect on surrounding vegetation. When it is gone, suddenly other trees and plants shift into high gear to take maximum advantage of the newly abundant resource. Birds and other wildlife are quick to make use of the changed environment too.

The tree-that-became-a-snag in our yard was suppressing nearby trees, and since it died, its neighbors have sprouted new growth from dormant buds on their trunks and branches (called epicormic branching). The thick new growth is fine for nest platforms and cover; Steller’s jays (Cyanocitta stelleri) are taking advantage. We watched a pair put together a nest in this limb thick with new growth (see video here). When trees snap off and lose branches naturally, the same thing occurs. This is why disturbances like wind and freeze damage create great habitat.

Thickened new growth makes better nest platforms

The tree pictured below was so close to its neighbor, that shaded lower branches died off. But new ones were able to re-sprout when exposed to sun. The tree has thick branching from dormant buds on the limbs, and epicormic buds on the trunk that exist for just this moment of newly available light.

Light gaps are important for regeneration in dense forests, and for diversity of species. This is where seedling trees, shrubs, annuals, and perennials get a start. Their blooms provide nectar for pollinators and food for animals.

A few Thoughts About Snags Part I

Biological richness of snags and logs

During some restoration work here, we had three largish Douglas firs limbed and topped for wildlife snags. We didn’t kill them, because the thinking at the time was that live damaged trees remain standing longer to provide wildlife habitat. Ten years on, these guys do, in fact, still have a lot of life left in them. One study1 found that 23% of non-fatally topped Douglas fir (Pseudotsuga menziesii) were still alive 16-18 years later. Raptors can use them for perching, and the thick growth stimulated by cutting the leader makes a wide nesting area. The height and breadth of a tree provides the structural diversity of vertical space and occasionally cavities, but see below.

Dead trees equal higher biological diversity

I would argue that dead trees might be more useful than live snags. Once dead, biological resources in a live tree’s wood, sequestered during its lifetime, become available to microbes, fungi and arthropods. That is a gateway to creating living space for cavity nesting birds, mammals, bees, and other wildlife.

At first, even a dead tree is still hard and intact. Woodpeckers have to wait awhile before they can really tuck in and excavate nest cavities. Also their prey may not be able to get past a live tree’s defenses, which are many.

Recent heat waves and droughts have hastened death for some trees.

After defensive chemicals leach from the dead tree, wood-rotting fungi (ubiquitous in Pacific Northwest forests) move in to soften up the wood and begin the recycling process. One of these pioneers is a mushroom called veiled polypore (Cryptoporus volvatus). Fruiting bodies (mushrooms) appeared on the snag above, soon after it died, indicating that the mycelium had already invaded the sap wood.

This fungus is called a veiled polypore because it forms a pouch or envelope over the pore layer where spores are produced. The Latin name is more descriptive: hidden pores, covered by a sac-like membrane. At first look, one might mistake it for a puffball type mushroom (I did).

Bark beetles and many other insects take up residence inside the moist and nutritious interior. They may be eating or parasitizing each other, or just taking advantage of the warm, moist, and protected space and available mushroom food. Beetles carry spores into the bark when they bore into the sap wood of this or other dead and dying trees. Billions more spores are shed and dispersed via air currents.

This fungus colonizes recently dead or almost dead trees, causing sap rot that softens the wood under the bark. That’s the beginning of an explosion of diversity and nutrient recycling: microorganisms, invertebrates, birds, mammals, and others use the resources built by the tree over its lifetime. Some, like molluscs, newts, frogs, and reptiles, take advantage of the spongy, water-retentive rotting wood and physical shade during the dry season. Others forage for insects, eat algae, or feast on abundant carbon in the wood itself. A large log on the ground even attracts nitrogen, an essential plant nutrient in short supply in the soil.

When the wood is soft enough, primary cavity nesters2 begin to chip off bark and make holes. Secondary cavity nesters follow: squirrels, owls, and others that don’t excavate but need the holes for nesting and protection. Cavities are in short supply in modern landscapes and birdhouses do not replace the complexity and richness of large dead trees.

Whether as a standing snag or a log on the ground, dead and partially dead trees provide long lasting ecosystem benefits. Snags and large downed logs rule, obviously! Let’s keep more of them (looking at you Oregon Dept of Forestry).

Up Next: Part II – Structural Diversity


Photos © 2020 Taylor Gardens. All rights reserved. Please request permission if used. No commercial use allowed without prior permission.

Forests and Pollinators

Here in western Oregon we are gifted with many habitats and a variety of native plants for most any growing conditions. Wet soil? Try plants that love the ditches like camas, showy milkweed, or goldenrod. Shade? No problem – forests are full of shade loving shrubs and perennial plants. Gaps in the tree canopy and edges along roads or meadows are sunnier and packed with resources that increase habitat resilience and biodiversity.

Marginal land like ditches, roadsides, and rights-of-way might sound useless, but they are anything but that. Just check them and see how mosses, plants and animals take advantage of them. “Marginal” can mean not the greatest, or alongside. Land alongside roads, tracks, fields and power lines make up a tremendous amount of acreage.

Pollinators require nectar and pollen resources, but equally important is the availability of protected overwintering sites like leaf litter, large ferns, and tree cavities. Undisturbed forests, and even timber farms provide these in abundance when managed properly by leaving or adding plants that are often classed as non-timber resources. You might not be able to sell them, but they will enrich your forest in many hidden ways.

Agriculture and development daily gobble up land that was previously uncultivated or unnoticed, and that reduces refugia for native plants and animals. An example: unsprayed roadsides are one of the places milkweed can flourish unmolested to give monarch butterflies a chance to lay eggs and fuel up on nectar. Milkweeds, in fact, are some of the most prolific producers of nectar for lots of other pollinators too.

Vine maple is a favorite nectar plant for insects and hummingbirds

Oregon grape, vine maple, cascara, Nootka rose, Pacific ninebark, salal, spiraea and ocean spray are all common forest shrubs that provide superior habitat for pollinators. If your forest is lacking in diversity, you can plant these species either in the understory or along forest edges. If you have open spaces, you may even want to consider planting “pollinator patches” of native flowers, such as lupine, meadowfoam, clarkia, selfheal, goldenrod and aster. Many of our common forest plants, and indeed our food supply, may depend on this kind of proactive conservation work!

Kirk Hanson, Forestry Director
Northwest Natural Resource Group

One advantage to growing forest-adapted shrubs, wildflowers and trees is early season nectar. The ethereal white flowers of Osoberry (Oemleria cerasiformis) appear against the green forest background as early as January. Tall Oregon grape (Mahonia aquifolium) may accompany red flowering currant (Ribes sanguineum) to dramatic effect. The dense creamy sprays of goatsbeard (Aruncus dioicus) on shady edges attract multiple species of native bees.

Late season nectar is often scarce because our hot, dry summers force most plants to get their reproducing done early. Summer dormancy is a survival strategy that produces yellow leaves on perfectly normal osoberry late in the season. However, goldenrod (Solidago spp. and Euthamia occidentalis), Aster spp, and rabbitbrush (Ericameria sp.) are used extensively by insects late in the season. With a little moisture, some perennials will even bloom a second time.

Pollinators aren’t the only beneficiaries of wise planting. Birds, mammals, and predators all use the fruits, structures, and protection that a diverse forest provides. Lower levels of pests and higher soil moisture and fertility are a few of the by-products for landowners and farmers.

Of course an equally powerful way to protect wildlife and pollinators is to reduce or eliminate agricultural chemicals on your property. Properly using those you need, in small quantities, and with great care with respect to timing of application is essential. If you live in Yamhill County, join the Yamhill Butterfly Gardeners, the Native Plant Society, or get in touch with Taylor Gardens for a consult to explore your options.

Serviceberry (Amelanchier alnifolia)
Tall Or grape + red flowering currant
Iris tenax
Can you see the flowers on the salmonberry? (Rubus spectabilis)
old growth Evergreen huckleberry (Vaccinium ovatum) with a ground cover of Maianthemum racemosum
Bleeding heart (Dicentra formosa)
Many native pollinators use western goldenrod, often at the same time
-Photo: Sonya Wilkerson
Good old showy milkweed (Asclepias speciosa) is making a comeback for feeding monarch butterflies
Goatsbeard (Aruncus dioicus)

Milkweed and Monarch Butterflies

Monarchs are probably the best ambassadors for conservation. They are popular, great looking, and they need habitat from their wintering forests in Mexico all the way to Canada. Here on the west coast we have our own population that winters in California. Because the midwestern migration route can be as long as 3000 miles, if farmers can be convinced to use farming practices that help monarchs, it helps a ton of other species, over a huge area. This means no Roundup Ready crops, because that means no weeds on the margins of agricultural fields, and that is where the monarchs are. Even better is organic farming with hedgerows, beetle banks, conservation cover, and windbreaks with some evergreen trees. By advocating for uncultivated margins, Aldo Leopold had the formula in the twentieth century.

Monarchs are dependent on milkweed (Asclepias sp.) because their caterpillars only eat milkweed. Adults lay their eggs on milkweed as they make a multi-generational journey from Mexico each year.

As Monarchs head north, they feed on nectar, stopping at night in protective tree canopies. The first and second generations from Mexico will die before the population gets where it’s going. After newly transformed butterflies emerge from chrysalises they continue on their leg of the migration relay. There may be three or four generations of butterflies by the time the population reaches the farthest point in their travels. In the fall, the last generation will travel all the way back south, looking for sustenance along the way. After overwintering as adults, they will head north again. It’s amazing that this works at all!

Here is an awesome time lapse of the entire monarch lifecycle.

If you’d like to have a look at some nice milkweed and possibly an egg, caterpillar or monarch, check out the gardens at Winter’s Hill Winery and Vineyard. (That is some butterfly-friendly wine, and so delicious!!)

I recently found these clumps of milkweed on the side of the road:

milkweed1_2 milkweed2_2

If no one sprays it before it goes to seed I will collect seed and grow out plants next year. Having planted a few this year, I can say they are a bit slow to get going but once established they thrive on neglect. A seasonally wet ditch in the sun is best. A wet prairie is ideal. That way the monarchs can find them.

While I was photographing these clumps, a honeybee and a western tiger swallowtail butterfly came by.

Milkweedbee_2 milkweedbutterfly_2

It’s Raining – But Only Under This Tree

I had an arresting experience when I went out into the woodland the other day. It has been extremely dry this winter in Oregon, but there is often a lot of fog. As I walked under one of the larger Douglas firs there was a sound of dripping rain on dried oak leaves and yet, it was not raining.

I’m not sure if I have ever experienced fog drip first hand in quite this way. I learned about it many years ago as a very significant (in the statistical meaning) source of ground water and soil moisture in the western Cascades.

Have I ever been in the woods when they are dripping? Yes, but standing under one single tree, that is collecting and dropping water is kind of eerie when everything else is quiet, the ground is dry, and it’s just very foggy. Being present as a tree essentially waters itself and channels the water into ground storage, reveals how trees = water = more trees and life.

So, come along with me and experience it for yourself. You might be able to see the raindrops falling in this cellphone movie:

Here, stand in the open where no rain is falling, and look back toward the mixed oak and the big Doug fir in the ravine. These trees were left behind when the forest was logged the first and/or second time in the last century. We left them too, when we thinned trees to revive the oak woodland. They protect a riparian zone of seasonal streamflow – the source of some of that flow is now apparent! That’s a Steller’s Jay imitating a Redtailed Hawk in the background.

So, why fog drip under conifers and not oaks (I asked myself)? I believe that the answer lies in leaf architecture. Moisture runs off the vast surface area of thousands of needles intercepting fog. Oaks are leafless in winter, but besides that, they support a huge biomass of lichens and mosses, which are designed to soak up nutrients and water from the air, as it’s their life support. Hence, lichens and mosses may tend to increase the humidity around a tree, but they sponge up rather than repel moisture like fir needles. Fir needles don’t need the moisture – they send it to the roots where they can use it.     Wow.


Closeup on Forests of the Pacific Northwest : Image of the Day.

Had to share something I stumbled on while looking for a satellite image of the vast Eastern Oregon wetland that is the Malheur National Wildlife refuge. The accompanying text is very important. These carbon sinks are old growth conifer forests, not white oak woodlands, so a little departure from this blog’s theme.

Another feature not mentioned in the text is that “checkerboard lands” are very clearly defined on this map. These are our legacy from US government donation of the spoils of conquest to the railroad barons more than a century ago.

Prairie Field Day Arrives – May 31


This gallery contains 13 photos.

Many thanks to Amie Loop-Frison of the Yamhill Soil and Water Conservation District and her prodigious organizing skills to pull this off. It was a beautiful day, a fun tour, and an inspiration to see so many people interested in … Continue reading

Resident WBNs


The day before I took on the Scotch broom (previous post) I indulged in a day of scouting for birds and plants. It is so much easier to see birds since the tree thinning! I finally got a picture of the white breasted nuthatch (there are at least 2) in its element, with a tasty morsel of some kind – nowhere near a feeder!

© 2013 Taylor Gardens
All rights reserved.

© 2013 Taylor Gardens
All rights reserved.

“The ecological vitality of a forest can be judged by how many large trees are lying around, feeding beetles, hiding salamanders, growing fungi”

I am reblogging this story by David Haskell, a scientist and natural history author that I follow. It is a great example of good ecological sleuthing, nice descriptive prose, and ecological principles that are very applicable to our own PNW forests. Read on!

Death in Nature – a look back and a new link

I recently read this article in the New York Times, and it reminded me that I had also written a blog post on the same topic. Of course the great scientist, Bernd Heinrich, has thought way beyond my musings, but there are parallel observations nonetheless.

Here is my humble previous offering.

And here is the real deal, scientifically speaking. I must read that book!

A Map Of Time, Time In Maps

This is a gallery of landscape changes in our little corner of the world. In a very short time (1994-2012), the local vegetation has been altered by land management quite dramatically. From our perspective (our 20-acre rectangle) it often seems overwhelming.

In 2005 we had a comfortable buffer of forest around us for the birds and wildlife we like to watch. We knew it was tree farm country, so logging was a given but, patchy as it was, it didn’t seem too traumatic. You can see the tree farms mostly blanketing the area in the earliest GoogleEarth map.

Then came a shift in land use – ‘conversion’ is the term – from timber to vineyards. Watch the photos as the trees begin to disappear. Vineyards and orchards sound like a sort of idyllic alteration, but think just a minute about what that entails. Conversion from old growth to tree farms is a step away from diverse, patchy habitat of a particular kind: spotted owls, flying squirrels, really big trees with a lot of carbon stored in their massive trunks, a lot of cavities for owls and other specialists. Old growth trees (250+ yrs) that store and hold – sequester – more carbon than any other type of forest. You can see that even in the earlier views, the connectivity between patches is important – those are corridors that allow wildlife and plants to move across the landscape either to escape the clearcutting or to find food or mates.

Timber farms, especially smaller ones cut in patches on a long rotation, (time between cuts), shelter many important organisms while they grow, and if those plants and animals are lucky, they can shift over to another patch when the clearcut begins. Technically, people are required to leave a certain number of trees and snags, but the rules about that are so lenient that it doesn’t really amount to anything ecologically important in most cases on private land. Federal forests are another story, as they are managed differently. The other thing about forestry is that there are relatively long periods between soil disturbance.

Now, step it up one notch with conversion from timber land to row crops, vineyards, or a hazelnut orchard. If you look, you can see that to the north and east of our 20 acres, all trees were removed, conifer, oak, even the ones that were formerly left by commercial forestry. Stumps were bulldozed, burned, and the land plowed. Two major changes that occur now are the absence of trees and shrubs, and soil disturbance on a regular schedule. Weed control and monoculture demand constant spraying, plowing, or both. All these activities restrict plant life and, importantly, affect the insects that can survive in disturbed habitat.

Unless a farm, orchard, or vineyard is conscientiously managed to leave patches of undisturbed habitat for native ground nesting bees, predatory insects, and other beneficials, the landscape is a depauperate one compared to a natural one.

In the gallery above, you can view the transition from 1) patchy timber harvest to 2) clearcuts on a larger scale (there is a large absentee landowner to the north and east of us who is progressively extracting all the monetary value from his timber, then selling off the land) then 3) conversion to vineyard to the east and north. Note the extremely clean patches and rows of plowed and planted crops. Oak trees that were left after cutting douglas firs were stripped off the land and sold for firewood. Thankfully, a few trees were left around a low spot on the east side, that is the source of a stream that flows across our property and down to Deer Creek. However, our hydrology is permanently altered. Erosion from the force of high water flows, and lower flows in summer are byproducts of vegetation stripped off the soil surface.

Next week – the closeup view of our patch before and after we acquired it.

The good news…

The post on the shrinking Willamette River system was unhappy. At the end of that post I mentioned that restoring the ecological functions of the river involved working with modern land use and human structures in the landscape. Here is how that might happen. This week in our Master Naturalist class, we visited a farm that is a step in the right direction.

Look at this current view of a section of the Willamette River:

Willamette River aerial view showing remnant channels and oxbow lakes

If you zoom in you can see labels for lakes along the right (east) side and over to the left of center. These lakes are hydrologically connected to the main river. Here is the diagrammatic view of the river at the time of European settlement and as sloughs and side channels were drained for agriculture from the mid-1800’s till now :

Size and complexity of the Willamette River Channel over time

Aerial views give a different perspective on the adjacent wetlands and their importance to a river. Those lakes in the color map are side channels and oxbow lakes that were part of the river at one time. During high flows and floods, juvenile fish (like the endangered Chinook salmon) will find refuge in side channels; there they grow larger and hide from predators. When the water level recedes, they move downstream, better able to survive the rigors of life in the main channel as they head out to sea. That’s just one of the many functions of channels and sloughs in adjacent wetlands. And one species. Another ecosystem service provided by these wide flat spots is to dissipate the force of stormwater coming down the channel and spread out the volume of water during high flows.

In this farmer’s field there are several native species of fish that hang out in the winter when the water rises (yes-IN the field! remember this was once the river). He has built water control structures to facilitate their movement in and out, so they don’t get trapped in the side channel when it dries out. He has planted trees and hedgerows along the river for habitat. These plants also provide a buffer to absorb fertilizer and insecticides, and protect the river bank and crops.

Here is a closer aerial view of the sloughs (the dark green shrubby areas between fields) and banks planted with trees. You can also see another feature that all farmers should have right in the field – hedgerows of native plants. They look like thin dark stripes in the field in the lower left part of the aerial map.

This view on the ground is dramatically set against the big storm that was on the way this weekend to dump about 2.5 inches of rain on us. The hedgerows are mostly hardhack (Spiraea douglasii) and the one in front is overrun with blackberries. Both provide a lot of value as insect rearing habitat. However, a mix of species provides multiple generations of beneficial insects nectar, food, and places to pupate. That saves on pesticides.

What do you think? If every farmer or landowner with property near a waterway was to enhance one ecosystem service their patch provides, instead of thinking only of protecting crops, houses, or buildings, could we integrate enough habitat and resilience back into the Willamette River system to bring it back to health? Would residents downstream perhaps be willing to provide assistance to upstream residents to help prevent flooding in the streets of Portland?

One last note: buy Flav-R-Pac and Santiam brands – it’s a local farmer’s cooperative that this farm belongs to, and it keeps farmland out of development. If you buy organic – look for the Ladybug logo on produce – this farmer’s neighbor grows organic produce for them. That’s a whole nother story.


1: falling short of natural development or size

2: impoverished depauperate fauna>


Middle English depauperat, from Medieval Latin depauperatus, past participle of depauperare to impoverish, from Latin de- + pauperare to impoverish, from pauper poor — more at poor

First Known Use: 15th century

This Dickensian word perfectly describes the flora and fauna of the modern world. We are now living among truly impoverished, pauperized landscapes.

In my Oregon Master Naturalist class this past week, we looked at this illustration of why the Willamette Valley biodiversity has plummeted since the mid-1850s:

Size and complexity of the Willamette River Channel over time

On the left is a diagram of the river as it was in 1854. You can see the narrowing, but from a physical point of view, consider the thousands of miles of edges, and surface area that were in the original system. The complexity was mind-boggling, and is the key to understanding the importance of river/wetland systems.

By the end of the century, the side channels and sloughs had been blocked or drained for farmland, the river was straightened for navigation and, significantly, an enormous quantity of large trees were removed from the channel. The result of these activities was a disconnection of the river from surrounding landscapes. The forests no longer contributed nutrients, shading and large woody debris. That impoverished the salmon support system of food and cover, as well as cool water and spawning gravel. Side channels and floodplains no longer dissipate the energy of floods, so Portland streets get inundated during big flood years. It is the equivalent of smashing up a finely tuned, complex and delicate mechanism. A fine clock for example.

The underground hydrology of the river systems is also very complex – with water entering and leaving the visible stream below and along the edges for some distance from the banks. The riparian zone is that belt along a river where you see green vegetation in a dry landscape, or where the tree type changes from conifers to mostly leafy deciduous trees. It can be 1.5 to 3 kilometers wide, yet most laws only protect less than a few hundred feet (sometimes only 50 feet) on either side of a stream.

The loss of wetlands is an enormous cost to us today, and surprisingly the loss from the tiny fraction of original wetlands continues at a rate of about 3% per year, despite laws to protect wetlands. (Previously, the loss was caused by farming, now the primary reason is development.)

Restoring the pauperized landscape: The replacement of lost function is the guiding principle in riparian and wetland ecological improvement projects, rather than “restoration” to an original state. People are just getting the hang of how to replace some elements of river/wetland systems so they perform their original services to wildlife and people, working around human structures to do so.

Ambitious plans and fall activities

I have decided to sign up for WordPress Post-a-Week. Although I admire and seek to emulate post-a-day people such as the Dragonfly Woman, whose exemplary blog sets a standard, weekly posting is my own new ambitious goal. However, due to my recent low production there is a current backlog of ideas and photos so I might be barraging you subscribers with several short ones. So, off we go.

Here is the view from Gopher Valley as late summer burns everything to a crisp:

I am embarking on part two of Oregon Master Naturalist training: on-site classes and fieldtrips for the Willamette Valley regional specialization. Last fall I took an online course from OSU, where the Master Naturalist Program resides. This is a wonderful Extension program course and I’m in the first wave of students moving through online and on-site training. When I get done, I will sign up for volunteer hours working with a non-profit or agency, and eventually it will help me be a better tour guide for our restoration project here in Gopher Valley.

This Friday I will spend the day at the Straub Environmental Learning Center in Salem and on a fieldtrip to Baskett Slough National Wildlife Refuge (our neighborhood refuge) talking about historical vegetation and landscapes in the WV. On Saturday it’s off to Silver Falls State Park for another day of classes and fieldtrips in the park to learn about and observe geology. Two of my favorite subjects.

Here’s a trailer for an interesting movie project that gives a taste of what there is to know about the Willamette River and the valley. They need donations to help finish the movie so if you’re looking for something good to support, now is the moment!

Oh, the irony…

In April, NPR ran a story about shooting one species of owl to save another in Oregon. It just begs for commentary.

Although there aren’t any spotted owls on our place, this is an example – no, possibly THE example of the ethics and dilemma of ecological restoration and questions surrounding repair of damaged ecosystems:

  • Are the results of human-caused ecosystem change separable from change that occurs naturally?
  • If we are serious about saving species and habitat, how far do we have to go to change our own behavior that caused their decline?
  • Are we in a downward spiral – making the situation worse by reacting to the effects of our actions rather than addressing the true causes of extinction?
  • Is this whole endangered species recovery exercise going to work for some but not all species? Which species will be able to live with us?
  • Will that be enough to preserve the safety net we humans depend on to survive?

Okie doke, so in a nutshell here is the situation:

In the 1970’s, a biologist named Eric Forsman did groundbreaking research on the northern spotted owl (Strix occidentalis caurina). Forsman found that spotted owls depend on old-growth forest habitat. It was determined that they were endangered due to loss of old growth to widespread logging in the Pacific Northwest.

In 1990 the northern spotted owl was placed on the endangered species list. The Endangered Species Act (ESA) mandates protection for species if they are listed, plus a plan to bring them back from the brink. So in 1991 millions of acres of federal forestland were excluded from logging to save habitat for the northern spotted owl. All hell broke loose in the logging communities of the Pacific Northwest, because of their dependence on federal timber land. For an excellent account, see The Final Forest by William Dietrich.

So for the last 30+ years Eric Forsman and a lot of other biologists and managers have been working to bring the spotted owl numbers up by saving habitat. But in fact the numbers are sinking.

As early as 1998 reports about an aggressive cousin – the barred owl (Strix varia) – discussed it as a potentially game-changing threat to the spotted owl (The Owl: Spotted, Listed, Barred or Gone?). Now it has come to pass that yes, the barred owl is currently a big factor in the decline of the northern spotted owl. The biggest factor.

Where did barred owls come from? Apparently barred owls started moving west from the eastern US about the time settlers began plowing up the prairies and suppressing fire. They moved through Canada and Montana, and started expanding their range into the Pacific Northwest in the 1960’s. Was it because of us? Or would this have happened anyway? Impossible to say. The two species might have evolved from a common single species at the time of the last ice age – at least we can be reasonably sure humans didn’t have anything to do with that.

Interestingly, barred owl populations here did not explode until about 20 years ago – about the time the spotted owl was listed. Speculation about why this happened follows this line of reasoning: like many invasive species, at first there aren’t many of them, but gradually they become adapted to their surroundings, or perhaps their population builds to the point where they just produce a ton of offspring. Suddenly the population explodes – because they have few or no predators and parasites, or because they are just better at hogging resources.

In the case of the barred owl, not only are they more aggressive, they are omnivorous and voracious. Whereas the spotted owl is more retiring, and picky about what it will eat – which happens to be old growth-dependent species like flying squirrels and tree voles. Spotted owls are part of a wonderfully complex and delicate food web, involving truffles, arboreal mammals, and big tree cavities. Fat lot of good that did them.

Because barred owls scare off spotted owls (although not always – they also hybridise with them, meaning it is possible spotted owl genes could be lost or “swamped” by barred owl genes), and because they aren’t particular about what they eat, they have no problem supporting themselves at the expense of spotted owls. But when barred owls have been removed or shot, spotted owls show up again. This is where the idea of getting rid of the barred owls came from. But really, this is an idea that can’t get very far. If land managers could get past the outcry over shooting a sort-of native bird, according to Eric Forsman, “You could shoot barred owls until you’re blue in the face, but unless you’re willing to do it forever, it’s just not going to work.”

So were all those years of trying to save habitat wasted?

People who depend on timber for income, and who have suffered disproportionately during the recent economic recession are suggesting that okay, since you can’t save the spotted owl by setting aside habitat, it doesn’t matter. Let us start cutting timber in the reserves set aside during the 1990’s. This is the disadvantage to saving species instead of looking at the really big picture – people can argue that if we can’t save those species, we don’t need their habitats. But this would accelerate the degradation of ecosystems we all depend on.

…far from saying that the logging restrictions were a mistake, owl biologists largely insist that more forests must be spared, especially since heavy logging continues on state and private land.. .”If you start cutting habitat for either bird, you just increase competitive pressure.”

Besides the barred owl, It appears that other changes in the larger landscape have caught up with efforts to conserve spotted owls. A recent review on spotted owl protection lists wildfire as a major threat to spotted owls in drier areas of the Cascades (remember the Biscuit fire?). That is a result of first, more than a century of fire suppression and second, climate change and normal weather patterns leading to conditions conducive to fire in forests loaded with fuel.

In a landscape before habitat became so scarce, if a fire burned one part of the forest, animals and plants could survive in refugia or recolonize from neighboring undamaged habitat. Now that there is so little intact high quality habitat left and it is fragmented, it is a dangerously fragile situation – organisms may not be able to find a place to wait out a wildfire or there may not be an adjoining area that can donate species to it later. With only 10% of high quality intact ecosystems remaining, on average, in the Northwest (e.g. old growth forest, Willamette Valley prairie and savannah, shrub-steppe in eastern Washington) it’s no wonder things are falling apart.

Lots of species are suffering the effects of practices that began during settlement and development of the west. Saving iconic wild salmon runs has been a priority for decades – at least people like to say it is. But how is spending time and resources shooting sea lions and relocating Caspian terns that eat salmon congregating below dams helping the situation? It’s stopgap emergency action, not a solution.

There are currently 11 dams on the Columbia River; “…32 dams in the land mass drained by the Columbia River system (including other rivers), an area roughly the size of France.” Does this not suggest that all the efforts to plant trees in riparian areas, shoot sea lions, and barge fish around dams is really just window dressing? If we want hydropower and irrigation, large scale agriculture and forestry, we will not have wild salmon.

Salmon and owls are two species that are indicators of a healthy ecosystem. We need to recognize that our ecosystems are at risk, and while it is the job of land managers and biologists to manage species, it requires an effort from all of us to look at the whole and make changes that affect how we build our cities, farm our food, allow ourselves to live with other species.

Many species have learned to live with us – coyotes and crows are two that come to mind. The barred owl can be a member of this club too (they live in suburban and even urban areas). We consider them pests or invasive, and think we have nothing to do with how they came to be so numerous. But they are adapting to us, we facilitated it, and it is in fact all about us. Don’t blame the messenger.

The thing is, if we don’t attend to these problems, we may lose the ecosystems that keep us alive. As with past mass extinctions though, the planet will keep on turning. New combinations of species will appear. Maybe humans will be among them.

We love our vultures

The turkey vultures are back in the Willamette Valley. Familiar circling objects in the sky, sometimes first perceived by a passing shadow overhead. As this piece in Conservation Magazine notes, vultures’ decline worldwide could signal another hole in the safety net of ecosystem services that keep humans alive.

This fine portrait of vultures in the Neighborhood Naturalist reveals that the Cherokee call them “peace eagles”, and that the turkey vultures in the Americas are not closely related to those in Africa, Europe, and Asia, but to storks and flamingos! (Click down to page 3 for the vignette on vultures.)

Everybody Needs A Hedgerow

We can all appreciate the fact that bats and birds eat a lot of insects. They control populations of pests that would otherwise destroy a lot of vegetation.

That is one example of an ecosystem “service”. Clean water, clean air, pest control, are provided by complex food webs, involving untold numbers of producers (e.g. plants, nitrogen-fixing bacteria) and consumers (insects, fungi, microbes, mammals, etc).

Now think about what happens if something goes wrong: species die, we add more carbon than our decimated forests and grasslands can absorb. Gradually we lose services that we need to live. The system breaks down, and no longer supports our health and safety.

Habitat is the key to survival for plants and animals. Wilderness and managed reserves are the highest quality habitat, but the space in between – the “matrix” (no, not the movie one – the real one) that we humans take up with cities, towns and rural agricultural land is so vast, and stretches across so many boundaries, that it becomes essential to manage it properly to ensure the integrity of the safety net that keeps us alive.

This was the topic of a recent article in the New York Times about a research paper that documents the toll of habitat loss in the matrix:

Every fall the calliope hummingbird, which weighs about as much as a penny, braves high winds and bad weather to migrate from Canada and the northern United States to as far south as Mexico, then back again in the spring — a total of 4,000 to 5,000 miles.

The journey is one of several dozen “spectacular migrations” — in the air and on land — that are chronicled in a new report by the Wildlife Conservation Society…But the report warns that these migrations are in peril.

As migration routes are disrupted, other species can be affected too — including humans. Take the case of migratory songbirds, whose numbers are down across North America.

In the spring, these birds eat 3,000 to 10,000 tons of insects each day as they travel. “It’s a legitimate concern,” said Dr. Wilcove, of Princeton. “Presumably with the decline of songbirds, insect damage to crops and forests could be worse.

New York Times December 19, 2011

That last sentence is a profound understatement. Unfortunately, this is not news. The great conservationist, Aldo Leopold began writing about it over 80 years ago. In one of the essays published after his death he addresses the issue in a nutshell:

The shrinkage in the flora is due to a combination of clean-farming, woodlot grazing, and good roads. Each of these necessary changes of course requires a larger reduction in the acreage available for wild plants, but none of them requires, or benefits by, the erasure of species from whole farms, townships, or counties. There are idle spots on every farm, and every highway is bordered by an idle strip as long as it is; keep cow, plow, and mower out of these idle spots, and the full native flora, plus dozens of interesting stowaways from foreign parts, could be part of the normal environment of every citizen.

Leopold, Aldo 1948

A Sand County Almanac: And Sketches Here and There

As much as we’d like to have unspoiled wilderness to shelter all sorts of creatures, the time is long past when there is going to be enough, or enough in the right places, for many species. We have to take care of the matrix lands – the places where we live.

Nature is not “out there” it’s here where we live.

What’s needed? Well, the best case is that there will be some connected places that afford the essentials for wildlife:

  • food
  • water
  • shelter and resting places
  • places for homes

Here’s how Leopold explained why we have to conserve habitat patches within farmland:

A city consisting of endless restaurants and dining rooms, with no bedrooms or living-rooms nearby, would support about as many people as Iowa supports upland game birds. Birds cannot rest, breed, or dodge their enemies in one continuous soup-kitchen…Iowa’s problem is to induce the farmer to let some grass and brush grow.

Report of the Iowa Game Survey, Chapter One: The Fall of the Iowa Game Range (1932)

We all need hedgerows

Hedgerows are ideal habitat to give insects, birds, and other beneficial wildlife places to find food and shelter. They will create balance in the landscape and give you a chance to enjoy the diversity of life on earth. The great thing about hedgerows is, it is something we can all do to make a difference. If you link yours with your neighbor’s you have an even larger habitat that is more than the sum of its parts. And hedgerows can be any size – even a few shrubs will improve things.

• Hedgerows can be groomed or left to grow on their own.

• The best ones contain a diversity of plants native to your local area, of varying heights, and with different bloom times.

• Evergreens are exceptionally useful to wildlife and help prevent erosion and excess runoff year-round.

© Copyright Eileen Henderson and licensed for reuse under this Creative Commons License

• By choosing the right plants for the space, you will not need to “control” the growth of your hedgerow unless you want to. This one is wild – yours does not have to be.

Bare root plants and plugs from the Conservation District are small but inexpensive

I started a hedgerow along the access road from Gopher Valley Road this year. I’m looking forward to watching the plants grow and produce wildlife galore.

If you’d like help with planning, planting, grooming or pruning your hedgerow, I’d be happy to help you through my business, Taylor Gardens

A lot of biology: Rodents

Well, there are rodents and then there are rodents. We had close encounters with our beloved western grey squirrels last year. In a more sinister turn, I just realized there is a fox squirrel inhabiting the yard and, possibly, the crawl space. The distressing thing other than the prospect of evicting it from the yard and house, is that fox squirrels aren’t from around here. Not only are they not local, they are in the class of exotic, non native species that are also ecosystem destroyers. The mammalian equivalent of a noxious weed.

I wrote to the Oregon Dept of Fish and Wildlife to inquire how bad it was to have this invasive species on our burgeoning restoration project. The reply was quick and decisive – essentially, “kill it, kill it now”:

Fox squirrels are a nonnative non protected species and were brought to Oregon from the Eastern United States and have established themselves in urban and suburban habitat through the state. They are the most common tree squirrels found in Portland and have contributed to the decline of native squirrel species.

Fox squirrels are reddish brown in color with large bushy tails and tan undersides. Oregon’s fox squirrels are notorious for breeding “out of season” and infant and very young squirrels found later than October 1st and earlier than April 1st are typically members of this species.

They are true omnivores, because they have also been known to eat insects. Not only that, but fox squirrels are also not above robbing the eggs from temporarily empty bird nests. Fox squirrels can compete for food and nest sites with your local western gray squirrels. Now is the time to rid yourselves of this invasive species. Fox squirrels have no protection and can be shot or trapped on your property. They can not be relocated and should be euthanized.

OK, I agree.

  • But I am not a euthanizer of mammals this big. I have mousetraps, and occasionally I accidentally get a chipmunk in the trap, which is cause for hand-wringing. I have successfully set rat traps, I have trapped moles (I am doing penance for that – it was earlier in my life when I was ignorant. I like moles now, and I defend them to everyone).
  • I can’t poison them (that’s the coward’s way anyhow) because they will poison whatever eats them afterward.
  • I don’t use guns and my neighbor declined to use hers on them. I could not possibly drown anything.

Eds. UPDATE (May 2014):  Not actually fox squirrels. What we have are California ground squirrels. They are native, but probably increasing with landuse that encourages them, also our brush piles that are great habitat for birds, but also other animals. Three years ago we had one squirrel below the garden which turned into many in subsequent years. The extended family now inhabits many corners of the yard and our ongoing battle with them is chronicled elsewhere in this blog. Suffice it to say, they are tenacious digging machines, have all the time in the world to get around many defenses, and have lovely pelts that would make nice clothing. If they don’t get under the buildings, things are all happy between us.


Okay on to another rodent. We live in Gopher Valley. We have lots of gophers. Also lots of signs on telephone poles advertising gopher “control” as if it were a standard maintenance procedure like mowing your lawn.

Here’s the deal with gophers – they ARE from around here, and they’re part of the ecosystem. They have a niche and fit in like part of a jigsaw puzzle. I’ll let these nice biologists ‘splain it, because this video is very entertaining:

We have this species and one other in western Oregon, if my Internet surfing is correct. The other is the Camas Pocket Gopher Thomomys bulbivorus – how appropriate because there are so many species of bulbs here. In the process of eating bulbs, they redistribute them (if you’ve ever dug up bulbs, you remember there are smaller baby ones that get inevitably get left behind), mix them with soil and aerate the seedbed, thus promoting the growth of more bulbs. Gophers are one of the factors responsible for the abundant bulb fields that existed before large-scale development and agriculture. They add fertilizer to the soil, too.

Gophers are endemic, functional species of the wild ecosystem, but of course once agriculture and horticulture enters the picture, they become pests. People think they need to control them in order to carry on the soil-compacting, mono culture farming of economically important crops like, um, Fescue for suburban lawns.

Consider this passage from the Fish and Wildlife Service fact sheet on the mazama pocket gopher:

Current subpopulations of Mazama pocket gopher continue to be threatened by loss of prairie habitat due to residential and commercial development, invasive plants, and encroachment of non-prairie plants due to an altered fire regime; small-population effects; trapping and poisoning; predation by cats and dogs; and trampling and crushing of burrows due to heavy equipment use.

Who can cope with that and survive? Pretty good that there are still some around.

Here’s another thought: biodiversity is valuable because there are many species and many kinds of species adapted to a range of climatic and environmental conditions. If there are several species that can occupy a particular spot in the food web, that’s good, because redundancy equals protection against total loss of necessary species in case of say, climate change, or massive disease outbreaks. Here is the full list of subspecies (genetic variants, below the species level) of this one gopher in this little old corner of the US (western Oregon and Washington).

Mazama pocket gopher Thomomys mazama (ssp. couchi, douglasii, glacialis, louiei, melanops, pugetensis, tacomensis, tumuli, yelmensis)

A couple of subspecies are already assumed to be extinct.