Author Archives: withrowb

Habitat Diversity in Streams

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Brad Withrow-Robinson, Forestry & Natural Resources Extension Agent, Benton, Linn and Polk Counties. 

 

We have written about forest diversity, its importance in providing habitat for different species, or a species at different seasons or at different stages of its development.  We have addressed the forest, trees and shrubs in particular, but the importance of habitat diversity applies to other parts of the forest environment too.  Like streams.

Guillermo Giannico discusses aquatic habitats along Griffith Creek, Benton Count.

We learned about the importance of having different stream habitats to support fish, insects and other aquatic life while on a recent Extension tour.    A stream can have many types of habitat.  The anatomy of a stream (the stream’s morphology) can be described in terms that are familiar to anglers: pools, riffles, glides, bars and tail outs.  Each term describes a different combination of water depth and flow that together provide a type of habitat.  You can see and often hear this:  Some parts are quiet (pool and glide), some gurgle their presence to those nearby (a riffle), while falls and a plunge pools announce themselves at a distance.  Aquatic biologists get excited about streams with a good mix of these habitats in a stream reach, just as wildlife biologists get excited by forest structure and snags.  Hmm.  Continue reading →

Big events of the past can still be seen in the landscape and vegetation today

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Brad Withrow-Robinson, Forestry & Natural Resources Extension Agent, Benton, Linn and Polk Counties. 

I was recently on a tour where we looked at how growing conditions, productivity and plant communities all change across the landscape according to elevation, soils, rainfall, aspect and other factors.  These are often included in the term “site productivity”.  These factors give important insights to the ability of a site to support different types of plants, and also how well they will grow there.  This capacity to produce biomass, or support tree growth is often expressed in the important forestry concept of site class as described in this article.

There is something odd about this rock….

We traveled from near the crest of the Coast Range back to the Valley floor to watch changes in site class and vegetation.  Our final stop was a rock sitting on a small hill beside a vineyard in Yamhill County, looking out across the Willamette Valley.

It is a large rock (about 90 tons), unrelated to any of the bedrock of the hill.  This rock helps tell a story of events during the last ice age that shaped the Willamette valley and its historic vegetation.  It influences the present, largely agricultural, vegetation as well. Continue reading →

Lovely lichens lurk in your woodlands

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Brad Withrow-Robinson, Forestry & Natural Resources Extension agent for Benton, Linn and Polk Counties.

The woods are full of living things, all contributing to the forest’s diversity: Trees; check. Shrubs; check. Woodland flowers; check. Birds; check. Obvious enough, right?
But there are all sorts of less-obvious things which are seen only occasionally, such as mushrooms (fungus), many often-tiny things like insects, or secretive things such as amphibians. All add to the diversity, and many play important roles in how a forest functions
Let’s take a look at some more obscure but fascinating members of the forest community: lichens. We’ve all seen them. They are everywhere, including your woods. But what is a lichen? Continue reading →

Watch for problems on woodland roads

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Brad Withrow-Robinson, Forestry & Natural Resources Extension  agent for Benton, Linn and Polk Counties.

In a previous post , I wrote about the value of roads for a woodland owner, as well as the responsibly to maintain roads to protect their value as well as our water resources.  Many family forest landowners have older, “legacy” roads.  These older roads were likely not built to today’s engineering standards, have lost some of their function over time, so are deserving of some attention and stewardship.

So what does that involve?

It likely begins with observation.  Make it a habit to get out and inspect your road system regularly.  Since water is a key element and force causing damage to roads, get out in the wet season.  Bring paper, make notes and keep them as a reminder of what you saw and did.

When on your walk, you should be looking for signs of drainage issues:  Water standing on the road, trapped water running down the road forming ruts, and water pooling in the uphill road ditch all indicate drainage issues that may leader to bigger more damaging (more expensive) problems. Continue reading →

Woodland roads worthy of attention

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Brad Withrow-Robinson, Forestry & Natural Resources Extension  agent for Benton, Linn and Polk Counties.

Roads are an important asset for a woodland owner.  Roads give access to the woods by foot and or vehicle, for some or all of the year.  This allows for recreation, management activities such as planting, weed control or harvest, and also fire protection.  Roads are an important piece of a property’s infrastructure along with buildings or ponds, and represent a significant financial investment.

Like other assets such as your house, car, pond or barn, roads need to be maintained to keep their practical values noted above, as well as value of investment.  But in contrast to the buildings or other infrastructure on your property,  with a road, a woodland owner takes on some legal responsibilities to maintain them.  That is because, for all their benefits to a landowner, road systems also have the potential to do significant harm to the environment by creating barriers to fish passage or allowing erosion and delivery of sediment to streams. A forest landowner is expected to keep roads in good repair to prevent such harm to the environment.  The type, timing and intensity of maintenance will depend on the type of road, location, construction and its use:  A rock road used to haul logs down a valley in the winter is very different from a dirt road along a ridge with light seasonal use. Continue reading →

Competition and Density in Woodland Stands

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Brad withrow-Robinson, Forestry & Natural Resources Extension agent for Benton, Linn and Polk Counties

As you know I am an outspoken advocate of thinning woodland stands, suggesting that for many (not all) family landowners “thin early, thin often” is the path to the future forest they envision.    Amy and I have posted numerous articles illustrating the many reasons for and benefits that thinning provides to family forest landowners.  This single practice applied with purpose, at the appropriate times, can shape a young forest into a uniform timber stand…. or a complex and chaotic habitat for wildlife.  The choice is really up to you.

 

OSU Extension released a new publication this summer to help landowners better understand, visualize and apply thinning decisions to their properties.  Competition and Density in Woodland Stands  EM 9206  describes in some detail the effects that different levels of competition has on a developing stand of trees, introduces Relative Density as  a way to determine the level of competition, and presents a unique new style of stand density table as a way to apply this information in the field.    The publication provides examples of how the tables can be used in determining if, when and how many trees to remove in a thinning, according to the objectives of the landowner.  It includes printable stand density tables for six different Oregon tree species.

Make this publication part of this winter’s reading list.

 

Fire is a fact of life here in the West

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Wildfire has plagued the western US this year. Photo by Dave Powell, USDA Forest Service (retired) Bugwood.com

Brad Withrow-Robinson, OSU Forestry and Natural Resources Extension agent for Benton, Linn and Polk Counties.

This year’s fires in eastern and southern Oregon, and especially California remind us that fire does not occur only in remote forest areas.  It is common in rural areas, can affect farm lands, communities along the wildland-urban fringe, and can even cross the boundary into densely developed communities.

The scale and intensity of fires across the west are increasing for many reasons including historic land management and fire exclusion policies, development patterns and recent climate patterns resulting in many consecutive years of intense droughts.  It is important for people in western Oregon to realize that we too live in a fire landscape, even though it is not as common as elsewhere in the state. Continue reading →

Fire Season is approaching

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Brad Withrow-Robinson, Forestry & Natural Resources Extension agent for Benton, Linn and Polk Counties.

Fire Season will soon be in effect in much of the Tree Topics reading area, as declared by the State Forester according to regional fire conditions (usually by early July). Here are some fire season basics to keep in mind:

To find out when an area is declared, you can visit the ODF Wildfire website and click on Forest Restrictions and Closures  section. There you can find links to an overview of the Industrial Fire Precaution Level (IFPL), closures and other information about fire regulations and restrictions.

If you choose the Current IFPL/Public Use (Regulated Closure) Chart you can find the fire level precaution for each of the ODF Forest Protection Districts by clicking on that district. Changes in precaution level and closures will be posted there over the summer, so it is a good idea to monitor this information throughout the season.

Please remember that even a Level 1 precaution requires you to carry fire equipment when in the woods. The motor vehicle or light truck (<=26,000 pounds GVW) requirements are:

  1. A) 1 shovel with a minimum 8-inch wide face and a minimum 26-inch length handle, ready for immediate use.
    B) 1 axe or Pulaski with a minimum 26-inch length handle, ready for immediate use.
    C) 1 approved A,B,C extinguisher, 2.5 pounds or larger (preferably 5 pound minimum), ready for immediate use.
    D) Exhaust system with muffler in good operating condition.
photo: ODF

Be sure you, your family or others using vehicles on your property are aware of this.  I generally make it a habit to carry these tools in my vehicle all summer.

Additionally, if you are using a chainsaw, each saw must have a shovel (meeting above standards), ready for immediate use; an 8-ounce (larger preferred) fire extinguisher, ready for immediate use; the standard exhaust system (spark arrester screen) must be in good operating condition; and the operator must stop the saw before fueling and move the saw at least 20 feet from fueling location prior to starting.

Please be FireWise, alert, aware, and pro-active in fire prevention. Be aware of how and where you park your vehicle, since exhaust system components have been known to ignite dry grass.  We’ve had a number of reminders recently that western Oregon is primed for wildfire each summer.  You don’t want to be part of the next one.

 

Another rough year for Willamette Valley trees Part 2

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Brad Withrow-Robinson, Forestry & Natural Resources Extension Agent for Benton, Linn and Polk Counties

In my previous post, I summarized what I think we know about this ecological whodunit. In this post, I look at what it might mean for landowners in the area.

Now What?

Pouch fungus commonly appear one year after trees are attached by beetles like flatheaded fir borer or fir engraver. Phot by Dave Shaw, OSU Forestry & Natural Resources Extension

We seem poised for another stressful summer. May 2018 has turned out to be one of the driest on record, and we are unlikely to catch up in June. Long term forecasts are for another warm dry summer. We will just have to wait and see how it unfolds. But whatever happens this summer, I think we can expect to continue to see more sick, dying and dead trees. There are several reasons for this.

First, many trees are already stressed or injured by the past hot drought events and are in a vulnerable condition. While not yet lost, this stress makes them less resistant and more susceptible to the insects and diseases that are lurking about. A mild summer, or several mild summers would help. But even then they will not recover immediately. Their earlier stress and injuries also hamper their ability to recover and rebuild their resistance, even under good conditions.

An analogy might be of me falling off a ladder. The injuries I suffered when I hit the ground continued to affect my health and recovery long after I stopped falling (it is harder to exercise with a broken leg). It will take a while to recover, even if I stay out of trouble. It will take longer (or could kill me) if I keep falling off the ladder. For the trees, each of these summers is like another fall from my ladder.

Second, some trees are already lost. It may not be obvious, and they may still have needles, but they have been mortally wounded or have already been attacked by insects and will not recover, however our summer turns out. It is just a matter of time before those losses become apparent. Continue reading →

Another rough year for Willamette Valley trees Part 1

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Drought-damaged trees have become a common site in the Willamette

Brad Withrow-Robinson, Forestry & Natural Resources Extension Agent for Benton, Linn and Polk Counties

 

Many of our readers have been tracking this issue over the last several years through the articles on this site. But I imagine many of you are wondering what to expect next, or are being asked by friends and neighbors who are concerned about your trees or theirs. Or just wondering what is going on. What to say?

So, here is a synopsis of what I generally see going on, and the consequences. A bit risky to do, given the role of individual sites and specific conditions. But this is such a widespread phenomenon, it warrants some interpretation, even at the risk of over-generalizing. But I provide the antidote at the end: links to more detailed information.

 

It is hard to miss all the dead and dying trees in the area. I have been getting dozens of calls about them. So what is going on, and what is to blame? It seems time to revisit this sylvan whodunit: What is killing all these Willamette Valley trees?

Who is involved? Douglas-fir is by far the most frequent casualty, along with other conifers such as grand fir and some ponderosa pine. But trees of many sorts are being affected –

Drought symptoms may include dead branches, dead tops and low vigor. Or all of the above. Photo by Dave Shaw, OSU Forestry & Natural Resources Extension.

hardwoods as well as conifers, both native and non-native. Many of the usual suspects – different beetles and fungi- can be found at the scene too.

What is happening? Symptoms often include dying branches and dead tops, low growth and vigor, sparse crowns, what we have called the “Willamette Valley crud”. It is now often progressing to the death of the tree. This may be happening to individual trees or groups of trees. The younger trees are usually the first involved at a site, eventually joined by older trees.

Where is it happening? This is certainly a Valley-wide phenomenon. But within the Valley, we are seeing the most significant damage in certain situations more than others. Sites with seasonally wet, poorly drained soils, or sites with rocky or shallow soils, exposed south facing aspects tend to be most hard-hit. These are places that we think of as marginal sites for most conifer trees. Our conifers are well adapted to the area, but not every site. Continue reading →