Newton’s Paradox: Why fish prefer clearcuts to regulated buffers


Native trout in full sunlight on a warm day in the headwaters of Blue River, Lane County, Oregon, August 24, 2013. Photograph by Aaron L. Zybach.

This post is generally specific to western Oregon salmonid (salmon and trout) populations in relation to current streamside vegetation buffer regulations. The “paradox” in the title refers to the fact that research work done by Mike Newton and others clearly indicate that Oregon Department of Environmental Quality (DEQ) regulations intended to protect native fish populations are, in fact, counterproductive – that is, salmonids do much better in streams that have been clearcut with no buffering vegetation than they do in streams with partial buffering; which in turn do better than streams with full buffering.

The post follows a discussion that John Persell and I were having on this blog regarding the effects of streambank vegetation on fish:

I made the point that I thought fish preferred clearcuts and sunlight to streamside vegetation and shade because they are cold blooded animals and there is usually more food where greater photosynthesis is taking place. Also, that they had responded to millions of years of fluctuating temperature changes in the rivers and streams they inhabited, and that streamside buffers did not provide much lasting effect on potentially hazardous (to fish) stream temperatures. In support of my statements I referenced personal observations (“fishing”) and the work of Mike Newton, a long-time friend and nationally recognized forest ecologist at Oregon State University, regarding a paper he had written several years ago on that topic.

John responded to these assertions with some reasonable questions: “Over what period (time of day, point in spawning cycle, season of year) did Newton determine fish numbers and volume were higher in sunny clearcut areas? What was the size and depth of the stream? At what life stage were the fish? It seems there are a lot of factors to consider before determining fish like clearcuts better than uncut areas.”

John’s challenge caused me to confer directly with Mike in regards to his paper and his own thoughts. As fate would have it (to coin a phrase), Mike was just completing a major article on that very subject, Managing Riparian Forests and the Paradox of Streamside Regulations, for the SAF Journal of Forestry, and was also getting prepared to present his findings to both the regulatory Oregon Environmental Quality Commission (a sub-set of EPA) and to the Oregon Department of Forestry (ODF). These works included references to ten or so reports showing that fish prosper more in clearcuts than in buffered or uncut streams, beginning with Murphy and Hall in 1981.

Several references were listed in the materials Mike provided me (including Murphy and Hall), a selection of which I posted for John’s benefit in regards to his questions:

These linked references also serve for the few citations I have included in this post. I have also provided several PDF files from Mike and from my own records at the end of this post, for those interested in original source materials.

The importance of stream temperature to salmonids

One of the earliest studies of the relation between water temperatures and salmonid populations was by Geoffrey Greene in North Carolina in 1950, comparing the different temperatures and trout populations in two streams: one that ran through a forested area, and another exposed to full sun as it ran through farmland. He confirmed that the “maximum temperature limit” for rainbow and brown trout was about 80 degrees Fahrenheit.

The maximum year-long measures of the farm stream varied from 65- to 79 degrees F., while the forest stream never became more than 66 degrees: which Greene considered the “optimum temperature” for brook trout. Neither stream reached 80 degrees during the year. From these findings he concluded: “once-productive trout streams can be restored by the control of stream temperatures through good watershed management.” To achieve that objective he thought it important to manage “all aspects of a watershed as a unit,” rather than be managed “on a piecemeal basis.”

Greene also recognized that trout obtained almost all of their food from aquatic organisms, “which are believed to thrive more abundantly at higher temperatures.” He therefore advised that “the most satisfactory practices would be those that raised the feeder stream temperatures to the maximum productivity of the aquatic organisms, yet did not increase the downstream temperatures above the limit of tolerance” via “the careful manipulation of vegetation and other kinds of land use practices.” Many of Greene’s findings and edicts remain as the basis for managing salmonids and water temperatures in fish bearing streams to this time.

Of greater scientific significance, because of geographic range, technical sophistication of measures, and sheer volume of research over time, is the numerous papers and reports by J. R. Brett, beginning in 1952 and continuing into the 1990’s. Brett’s work regarded the relationship of temperature and food supply for salmonids, and forms the basis of much of Newton’s writing and planned testimony on this topic — as well as provide context for subsequent field research Mike has performed on this topic during the past 22 years, often in collaboration with his long-time research assistant, Elizabeth Cole. Brett’s research showed that the warmer the water, the more productive for well-fed fish up to about 64 degrees F., whereas at 68 degrees well-fed fish grow at 90 percent of the maximum rates observed at lower temperatures; thus confirming, with greater precision, Greene’s findings.

Current Oregon regulations

I was involved in forest management issues as a reforestation contractor when riparian vegetation first became a topic of general discussion and new regulations in the Pacific Northwest during the 1980s. Prior to then the USFS even used to have “stream cleaning” contracts, where contractors were charged with removing all evidence of logging and other management activities from streams – even leaves and small twigs! The work made little sense: twigs, leaves, limbs and trees would keep falling into the stream after the workers left, and were being washed downstream to the ocean in any instance. The first contract I ever did of that nature was also my last, about 15 stream miles from the ocean.

Around the same time efforts were being made to save remaining old-growth trees from being logged and large amounts of land were thus being set aside and put off limits to logging. Soon, hydrologists and fish biologists followed this lead and began championing similar set asides for riparian areas, claiming the trees and shrubs were needed to 1) help off-set erosion and 2) provide good habitat for fish. Regulations followed, and harvesting next to a stream bank was soon forbidden. The argument quickly became how wide unlogged stream “buffers” should be, and regulations began being revised and more riparian land began being removed from management operations.

The research of Newton and Cole and others examined whether buffers lead to acceptable regulatory standards for fish-bearing streams. These studies revealed that small differences within buffer rules can make the difference between meeting or not meeting desired standards. Thirty-two streams with full regulatory buffers were measured over time, but State of Oregon forests had somewhat wider buffers than the current rules required, as set forth in the Protection of Cold Water Standard criterion for the Oregon Department of Environmental Quality (DEQ).

This triggered the question of whether wider buffers might be necessary. The DEQ study considered only buffer width on both sides of a stream, and water temperature, but did not consider other factors influencing the fishery; i.e., the very resource buffers were intended to protect, salmonids, did not factor into the findings – as a result, the several reports of general increase in fish productivity when clearcuts extended to the water’s edge (including those of Newton’s research) were not considered in the state-sponsored study of the use of buffers in meeting the regulatory criteria.

The history of disturbance

History tells us that fish have evolved and survived disturbances far more severe and widespread than clearcut logging, including: windstorms, catastrophic wildfires, volcanic eruptions, mass flooding, major landslides, etc. Such disturbances have almost always resulted in significant changes to streamside shading. Native fish have therefore survived and evolved with fluctuating stream temperatures — daily, seasonally, and occasionally. Their ability to swim to more favorable conditions during these changes should not be discounted.

As one result, the DEQ standard of 64 degrees F. for most of the salmonids and their habitats in Oregon fits neither the streams nor the fishery. The streams vary so much, and the environments in which they flow vary so much, that one standard cannot be made to adapt the fisheries that are acclimated to those streams. Neither the streams nor the fish are as homogenous as the standards; they never have been and they never can be.

Research Methods

The DEQ criterion for protecting the cold water standard is that no forest practice shall allow an increase in the 7-day mean temperature of water of 0.5 degrees F. or more downstream from a forestry operation, regardless of the natural temperature of the stream. This requirement eliminated any forestry operation intended to maintain the riparian forest — or to provide improved growth and health of affected fish. A technical problem is that existing temperature measuring equipment is only sensitive to plus or minus 0.32 degrees F., with a range of 0.64 degrees. Moreover, year-to-year variation in natural stream temperature is well over one degree. That means the only way to enforce this criterion is to require that there be no change at all in the riparian forest cover.

Germane to the above considerations is what, other than temperature, limits primary productivity of streams. Answer: short-wave light energy, and the photosynthetic process that supports the food chain. Newton and Cole’s research in the past 22 years has employed well over 100 thermistors registering summer-long stream temperatures along several streams. Their placements bracket clearcuts, partial buffers, and ODF’s Best Management Practices (BMP) streamside buffers. The instruments have recorded years before harvests and 5-17 years following harvests of several kinds.

Study streams range from eastern Douglas County to northern Lincoln County, all in western Oregon, in both the Coast and Cascade mountain ranges.  The work is part of the Oregon State University (OSU) Watershed Research Cooperative (WRC), an organization with several other large watersheds under close examination. Streams in the WRC study range from maximum summer temperatures of 50- to 68 degrees F. – all well within the desired range of temperature conditions for salmonids.

Newton and Cole’s research within the WRC involved four low to medium elevation streams with basins of 600 to 1000 acres each to determine how the arrangement and amount of streamside buffers in clearcut units influenced stream and air temperatures. Conditions included no-tree buffers, partial buffers 40-feet wide, and two-sided BMP buffers 50- to 100-feet wide. Impacts of clearcut logging on stream temperatures were determined based on time series analyses of post-harvest trends compared to pre-harvest trends.

Research Findings

Trends for daily maximums and means significantly increased after clearcutting in no-tree buffer units. Partial buffers led to slight (less than 4 degrees F.) or no increased warming. BMP units led to significantly increased warming, slight warming, or no increased warming, depending upon the stream. The effects of clearcutting and different buffers on daily minimum temperatures also varied by stream. Maximum temperature peaks were not maintained in downstream units; that is, elevated temperatures quickly returned to average stream temperatures within short distances.

Clearcutting led to increases in daily maximum and mean air temperatures above the stream for most buffer designs, with the greatest increases in the no-tree units. Changes to daily minimum air temperatures varied among buffer design and streams.  Although there were some inconsistencies in trends with different buffer designs among the streams, there were also some differences related to buffer implementation, changes in radiation, and stream features.

Brett (1956), Brett et al (1982), and Sullivan et al (2000) have all described tolerance of fish to elevated temperatures, the ability of fish to adapt with only 24 hours of adaptation time, and the very critical role of food availability with rising temperature. Viability of fish at temperatures 77 degrees F. and above depend on duration of exposure. The importance attached to stream temperature in regards to fish has been widely cited, but seldom with respect to the variability with which fish can respond within a range of responses.

The differences between units in fish biomass and other parameters were negligible before clearcutting in the spring of 2005, and all cut units increased in the three years following logging. Clearcuts with no buffers showed the largest positive response — but all cut units measured better than any unlogged units.

Peak temperatures above 64 degrees F. are necessary to achieve mean temperatures in the optimum range for salmonid metabolism.  The daily fluctuations of temperatures ranged from 2 degrees to 4 degrees F. in most forest streams within the study areas, with brief peaks and very productive means.

Stream reaches with some direct sun on them were the most productive for both the food chain and the fishery as long as they didn’t exceed 71 degrees F.  To this point, none of the study area streams have reached that level.

Temperature changes in logged units did not persist more than briefly downstream as water moved into other environments. Water temperature equilibrates rapidly with its local environment.  It naturally rises as it goes downhill, and remains very warm in interior valleys, gaining heat each day and losing it each night.

Why fish like light

Newton and Cole’s streams have compared buffer designs from no harvest to standard ODF buffers to residual-tree screens that shelter streams from the sun (one-sided buffer) between 9AM to 5 PM (daylight time), and units with no buffer other than scattered shrubs.  Brome Creek, a tributary to Hinkle Creek, the site of a major WRC basin-sized study in the western Cascades of Douglas County, demonstrated that full sunlight on the stream provided twice as much fish biomass as any other harvested unit, and all three harvested units produced more fish than any of the uncut units between harvested units.

Light clearly is responsible for fish growth. This was despite the complete clearcut units reaching maximum (but not mean) temperatures of 71 degrees F., and was frequently above 64 degrees.  The harvested units on Brome Creek ranged above 64 degrees before harvest.  Newton’s studies in several of these streams showed that the periphyton and macroinvertebrate abundance (“fish food”) was greatest where the most light reached the streams. On all streams peak temperatures were within the range defined by Brett et al (1982) in which fish growth was roughly 80-100 percent of growth observed at 62 degrees; the optimum.  This level of productivity is reached only when temperature exceeds about 57 degrees.  It is by no means a harmful temperature.

The argument against homogenized standards

Several factors weigh against a single set of criteria for all streams.  First, fish tolerate a wide range of temperatures.  Mortality of salmonids begins only when held above 75 degrees F. for an extended period of time. Above this temperature mortality becomes a function of the duration of time in which fish are subjected to warmer temperatures.

Brief excursions to such temperatures reduce feeding rate and raise respiration reversibly, leading to slow or even cessation of growth before mortality begins.  A single regulatory criterion (e.g., 64 degrees F,) does not capture the evidence that even though the constant temperature where growth is near or at maximum if well fed, 68 degrees F. is tolerated with only a 10 percent decrease in growth from the maximum; it is still a very favorable temperature.

Newton’s observations of highest stream productivity occurred when streams were fully exposed to sun, and when summer temperature peaks were well above the numeric criteria, revealing serious and costly flaws in the regulatory process.

The notion of requiring more shade when less shade equates to more biological productivity of streams represents a conflict between regulatory convenience (meeting a numerical criterion) and resource sensitivity (increasing fish biomass). Moreover, many streams are far too cold for optimum fish metabolism, and yet the Protecting Cold Water Standard prohibits operations that would provide both a more productive temperature range, but also improved food supplies.


Newton makes the following recommendations, based on his own research and the research of others:

1) The approach to stream quality should be one that first reflects that:

a) water quality in most Oregon commercial forest lands is excellent;

b) existing quality is protected by forest management that actively maintains streamside cover in direct proportion to stream temperatures; and

c) fisheries are not limited by temperature if good at the time of proposed harvest.

2) There should be flexibility in harvesting toward options that allow optimizing the harvest in order to improve fisheries productivity according to initial condition:

a) cold streams should be allowed (or even encouraged) to design harvests with no buffer; streams running 90-day mean averages of 59 degrees to 63 degrees before harvest should be allowed (or encouraged) to design a sun-sided partial buffer that would permit increased productivity in both fisheries and forest growth.

b) warmer streams should be allowed a sun-sided partial buffer plus a narrow screen of residual trees, which would increase forest and fisheries productivity with no appreciable change in temperature.

3) Such an approach is forest management friendly, fish friendly, and allows (or encourages) periodic entry into buffering forests in order to maintain optimum conditions — an activity not allowed by current rules.


Greene, Geoffrey E. 1950. “Land Use and Trout Streams,” Journal of Soil and Water Conservation, Vol. 5, No. 3: 125-126.

Newton, Michael 1996-2013. Select Publications and Brome Creek Presentation.

Seeds, Joshua 2011 Nonpoint Source Compliance With the Protecting Cold Water Criterion of the Temperature Standard. Protecting Cold Water Criterion Internal Management Directive, State of Oregon Department of Environmental Quality, Portland, Oregon: 12 pp.

Zybach, Bob and George Ice 1997. “Revisiting the Botkin Salmon Study,” IN: Proceedings of the 1997 NCASI West Coast Regional Meeting, Special Report No. 97-13, National Council for Air and Stream Improvement (NCASI), Corvallis, Oregon: 276-321.

50 thoughts on “Newton’s Paradox: Why fish prefer clearcuts to regulated buffers”

  1. Bob

    This is very interesting to a former southern US trout fisherman. Obviously temperatures down here often push the upper limits so more stream cover is very important as are restocking programs.

    This work resolves something that has always perplexed me. Pictures of people fishing in places like Scotland always seemed to show them fishing in open fields. The perplexity is gone – Thanks to you and Mr. Newton and company.

    Re: “1-b) existing quality is protected by forest management that actively maintains streamside cover”
    –> This really needs to be reworded. At first glance it seems to contradict everything in your summary extract. Maybe something like: existing quality is protected by forest management that actively maintains streamside cover in direct proportion to stream temperatures.

    The big question to me is what kind of erosion issues accompanied the decrease in Streamside Management Zone (SMZ) buffers? I assume that there was some significant slope involved and I know that you and I agreed previously that SMZ buffer widths should be directly proportional to percent slope.

    I found the reversal of commonly accepted “science” very interesting as I did the “discovery” that ‘one size fits all’ rules (BMPs) don’t get it. Once again, desperate fear inspired panic led to the adoption of unproven theory. When will we learn that there is always time to get the science right before we act?

    Am I correct in assuming that these studies didn’t reevaluate the benefits of in-stream structure science that upset the previous ‘keep structure out of the stream’ theories and BMPs?

  2. Gil: Thanks for your comments. Yes, I had trouble with that sentence too, which is a paraphrase of Mike’s lingo. I think the subtle key is “active management,” which includes logging and weed control. I hope the subsequent recommendations clarify that point and will work on a clearer version. Thank goodness I can always do editing on these posts! I like your suggestion, and may incorporate it after I get the PDF attachments and links in place.

    Erosion control is not so much a problem as one might imagine. Slopes are pretty stable and avulsions pretty much just change ownership patterns — which is the main reason I think we plant buffers in the first place. Seasonal storms, of course, move sediments downstream, but I’m not so sure trees have much to do with stopping those activities. Certainly Egyptian and Mississippi delta communities like erosion of this nature!

    Not so sure about the “desperate fear” angle either — I’m guessing it had a lot more to do with tenure, notoriety, and political opportunity that emerged from circumstances at that time. But then again, I seem to be turning into a conspiracy theorist in my dotage. And a curmudgeon, too, but I kind of like that privilege that comes with getting older.

    And you are correct in your assumption. I doubt there was any such “structure” in precontact times (“firewood” and canoes), but I do know there were a lot more beaver. If people need ponds for fish, stone and concrete are a lot cheaper and more durable than logs and chunks of wood — most of which floated away during our two major floods in 1996.

  3. Interesting that the issue of large wood is absent from this post. This post is misleading because it attempts to portray complete harmony between logging and fish. There is in fact unavoidable conflict between logging near streams and maintaining continuous input of large wood. Large wood being essential for stream hydrology, fish habitat, pool formation, spatial partitioning, energy dissipation, nutrient input/cycling, capture/storage/release of sediment, etc.

    • Darn right, a main reason for buffers over time is to provide large wood which most of us agree is critical for salmon habitat.

      • greg: Maybe most people agree on this idea, but maybe others prefer beaver ponds — of course, then there’s the fecal count problem. There is not much record of large wood in many streams during early historical times for lots of reasons, but there were abundant fish by most accounts. “Critical” is an important word in this discussion. I’d go with “helpful in many instances” if I were making such statements.

        • what data is there about incidence of large wood in early historical period.? After the fires I assumed that there was a lot of it in places (?)

          As one of the founding members of the beaver cult, I agree about them but I think that in many places their presence was ephemeral, dams get washed out in winter and they don;t do well on some narrow, faster channels. And they do seem to like to use large wood to anchor their dams in places.

          I did my MS work on beaver and stream restoration but have lost some of that faith. If someone wants to start a topic on beaver I am much into talking over that.

          They wanted me to give a talk about beaver at the university here in Hanoi but sadly, I do not have the pics with me. The conservation people have heard of them, and the kids see the cartoons with beaver so they know of them. You would be amazed at the TV shows from the US they see here. Yuck.

          They sure know a lot about Teddy Roosevelt’s conservation work.

          I gave a lecture yesterday about watersheds, Had pics of N CA and Yellowstone. I have to wonder how those went over. I did not even try to bring up beaver but maybe next week. The course is in english and their facutly person did his phd at Columbia so his english is good.

          I even broached the topic of fire ecology…….and they have fires here which have had impacts little studied thus far.

          BTW, at $250 billion, the US is the largest foreign investor in Vietnam. For them, the war really is over.

          The establishment of forest plantations across 3 million hectares of land is astonishing, they can get usable logs in 6 years which they carry down the hills on their shoulders. Wood products at $2.5 billion/year is one of the largest exports now, all recent. And mostly based on those plantations planted across degraded hill lands.

          Virtually all areas deforested by herbicides in the war have been successfully replanted for export products.

          • Greg: one of the biggest misconceptions about precontact/early historical time is that there was some kind of “natural fire regime.” No, there were people and they used wood — lots of it. Fire (light and heat and cooking and hunting and etc.), canoes, building materials, carving, etc., etc. Leaving wood in a stream would not only possibly block canoe travel, it would be like leaving a 5-gallon can of gas in a park today. People don’t waste fuel, for the most part, unless it is really abundant. And it wasn’t as abundant as today because of broadcast burning and using millions of acres to raise camas, acorns, huckleberries, and hundreds of other food, medicinal, fuel, weaving, and construction plants.

            The data I use include eyewitness accounts, drawings and photographs, and early land surveyor data to confirm these assertions. We know there were more beaver in early historical times because of Hudson Bay trapper journals, beaver pelt sales, and eyewitness accounts. The “natural fire regime” myth is based on computer printouts and a basic racist perspective that Indians had low population numbers, were extremely constricted in their movements on the land, and had no idea how to manage vegetation. Want huckleberries? Wait for the lightning, then. Want to light the barbecue? Better pray to the Gods. And so on.

            People have always liked freshwater, and creeks and rivers and lakes have always drawn people, whatever the population density. And people have always started fires, every day. And fires need fuel. Common sense and early historical documentation fill in the blanks.

  4. Tree: Why do you say large wood is “essential” to any of the things you listed? Why do you think this post tries to portray “complete harmony between logging and fish?” Why is it “interesting” that “large wood is absent” from a post that doesn’t have anything to do with large wood? Sounds to me like a lot of unsubstantiated comments from an unreliable source with a lot of opinions. Why should I think any different?

    • I’d just like to point out that while Tree may be an anonymous source, an “unreliable source” Tree has not been. This is especially true in the context of Bob’s anonymous and “unreliable” (and wrong) source regarding the Sitka black-tailed deer (Odocdileus hemionus sitkensis) over at this post.

      • Cool comment, Matt. That’s why they’re called “qualifying statements.” Also, exactly why I distrust anonymous sources, such as Tree or anyone else. “Wolverine,” on the other hand, was very helpful and provided excellent information. And there was far more than a grain of truth to the Wolf blog’s statement of FACT that the deer had been planted on the islands — which, if you will read the entire discussion, you can learn for yourself. Other than that, your silly “expose” is an obvious attempt to pick a verbal fight and I’m not really up for anything this petty at this point. Maybe you and Tree ought to do lunch one of these days. You seem to have a lot in common. I’m not interested.

      • probably because he works for an agency and has to keep a low public profile, not a bad idea. If tree were attacking people or being a social pest, I would prefer to see his name but he keeps it civil, Most of us are not in positions where we have to worry about our public profile, if Tree does, he shows good judgement. So who cares if he is anonymous?

        • greg: You are just guessing. If Tree works for an agency, why doesn’t he just say so? That’s what JZ and Matt V did; no problem. Plus “attacking” and “civil” are relative terms we could probably debate, given some of Tree’s past comments, too. How about if Tree “doesn’t” work for an agency, as you are guessing? Would that make a difference? I’m pleased you’re showing him the benefit of the doubt, but my experience with lectures from anonymous sources has been more bad than good, so you can count me as one who “cares.” If others want to try and have substantive discussions with anonymous people who don’t even indicate why they are remaining anonymous, that’s their prerogative. I have my own perceptions on this issue and comment accordingly.

    • His assumption is that buffers can supply large wood over time, a primary reason NMFS is adamant about keeping larger buffers while gordy reeves, the author of the NWFP riparian regs thinks they can be much reduced. I agree with gordy on that, since many trees that come down in those stream side areas will never make it into a stream since gosh, they fall sideways where they stay put.

      I do think the buffer thing is often overdone. Some people yawp about sediment, but sorry, I have a pile of pubs on sediment movement and much less sediment makes it in from logging than some contend. There is a lot of BS out there about sediment which I contend comes mostly from roads, esp the older road cuts.

      NMFS really seems to have religion on buffers but, this seems way overdone.

  5. Bob…the bottom line is, your version of forest management is tantamount to forest destruction. Even if you can “design” a stream buffer to optimize stream production for the fishery, you still have caused a blight on the land that is unacceptable. Granted, clearcutting may be preferable to the bottom line of the timber industry, it is not considered forest management to the majority owners of federal land. It is not wanted and will never be tolerated.

  6. Bob says ” And there was far more than a grain of truth to the Wolf blog’s statement of FACT that the deer had been planted on the islands,” referring to Sitka black-tailed deer on Prince of Wales Island. Bob cites no reference, and the literature I’ve seen says otherwise: “Sitka black-tailed deer (SBTD), Odocoileus hemionus sitkensis, are endemic to, and widely distributed along, the archipelago and coastal mainland of southeastern Alaska and northern British Columbia. Populations have also been introduced to Prince William Sound and the Kodiak Archipelago of southcentral Alaska.” For the geographically challenged, Prince of Wales Island is in the archipelago of southeastern Alaska. It is not the same place as Prince William Sound, which is about 600 miles north of CPOW.

    • Andy: If you read the complete string you will see that Wolverine (G. Gulo) has already covered this topic in spades. He is an expert on the topic and also covers specific references to deer being planted on the islands. I don’t know what CPOW is. 600 miles in Alaska is not very many, and I haven’t been there in more than 40 years. One more danger of citing anonymous sources on a blog, I guess.

      The best place to comment on that post is the link that Matthew provided. This post is about streamside buffers in western Oregon.

      • Sorry, “CPOW” refers to “Central Prince of Wales,” which is where the Big Thorne timber sale is proposed. I didn’t notice that you’d already been set straight — wolves were not introduced by humans to Prince of Wales Island, never have been, never were. But, if we keep eliminating their old-growth forest winter range habitat, the need to do so may arise in the future.

        BTW, I’m not the one who introduced wolves into this post — you did.

        • Andy: Nope. Matt did, for whatever purpose. Plus I never said the wolves were introduced. I merely said that from what I understood, the deer had been introduced on Alaskan Islands — I could include a link to that authoritative statement by an anonymous source on another blog if anyone is really interested, but I’d just as soon do that on the original discussion string, not this one. But I’d really rather not do it at all. The main point I was trying to make was that the post paralleled Botkin’s Chapter 3 and encourage those who were interested to read it. I’d encourage you to do the same, and would be interested in what you had to say on it. Also interested in what you think about Newton’s work on streamside buffers!

          • Your post, about “current streamside vegetation buffer regulations,” starts out: “The “paradox” in the title refers to the fact that research work done by Mike Newton and others clearly indicate that Oregon Department of Environmental Quality (DEQ) regulations intended to protect native fish populations are, in fact, counterproductive.”

            The problem is that Oregon DEQ has no streamside vegetation buffer regulations.

            So I couldn’t figure out what Newton is supposed to have been studying.

  7. Stream buffers, in many areas, were created to simply exclude equipment from creating skid trails, and not to exclude harvesting. The expansion of buffers has increased to ridiculous extents. I saw 300 foot buffers exceed the actual watershed boundaries on projects on the Bitterroot salvage. Some of those canyons were narrow and steep, and the 300 foot buffers excluded ridgetop skid trails. Ridiculous, indeed!!!!

    Many people feel that the fuels-choked (BOTH live and dead fuels) buffers present problems when wildfires burn very hot. I saw one such burned creek that looked like a sluice box, after high intensity fire wiped it out, then winter precipitation washed everything out.

    • Larry, your message reminded me of a quote from an article I wrote back in 2007, “Tahoe Fire Reveals Risks, Rewards of Fuels Management in Wildland–Urban Interface,” from the August 2007 issue of The Forestry Source. Dave Marlow, the Forest Service’s Lake Tahoe Basin Management Unit’s vegetation, fire, and fuels staff officer, said that the fuels treatments proved their worth during the Angora Fire, which burned 3,100 acres and 242 homes. Marlow told me that, in many cases, mechanical fuels removal is prohibited in riparian zones in the Tahoe Basin.

      “Many of the riparian zones have been difficult to get treated,
      and they’ve served as a wick for fire to move,” said Marlow.
      “With a decadent stand of lodgepole pine up and down the
      Angora Creek drainage, and jackstrawed lodgepole and other
      species, you can’t move that stuff without heavy equipment,”
      said Marlow. “When the fire broke out, we had 35–40 mile-per hour
      sustained winds out of the southwest. The wind pretty much
      blew straight down the drainage, and the homes happened to be
      right at the end of it. Do the math.”

      I recall that Chad Hanson and others opposed salvage harvesting of the burned area, saying that the black-backed woodpecker needed the snags.

    • Larry I have the same perspective — many of the buffers in high elevation draws simply become fuel-choked chimneys during wildfires and really fry the drainages they were intended to “protect.” The largest wildfire in Oregon a few years ago was the Deer Creek fire near Selma, which jumped a creek before taking off, made possible by the buffer that had been grown along it. Otherwise, it appears that it would have been a relatively small roadside burn, possibly started by a careless smoker in a car.

    • I agree, I checked plenty of buffers on Biscuit salvage and they were excessive, while some people took it as the bible. Matter of fact, the author of the NWFP riparian buffer regs also thinks that they are often too large, And even when buffered, I see no reason to exclude all harvest, I thought a no cut buffer needed to be a lot more narrow than often seen. And yes, the issue is ground impacts but often they were a lot more benign than some people thought. Logging practices on FS lands have improved a lot over the decades.

  8. Andy: Not sure what you are saying here. One of the references I attached was Seeds 2011, which specifically uses the example of streamside buffers for clearcuts to illustrate DEQ coldwater standards — which require buffers in most instances, as described in the post. I hope we’re not just playing word games or that you can clarify what you are saying. And to say to you couldn’t understand what Newton was supposed to be studying seems a little odd. I would think that you would know all about this stuff.

    OK, tell me what I should have written instead — the topic seems obvious so apparently I’m either too close to the problem, or there is a nuance of language I’m missing. Newton was studying water temperature variations in reference to logging and no-logging next to salmonid-bearing streams. Seeds explains what the DEQ standards are. Where is the confusion?

      • Andy: I am not following you. DEQ has water quality standards that require (maybe not literally, but practically) the retention of streamside buffers to maintain water temperatures. I think that is right, isn’t it? If not, are you referring to ODF BMP requirements? Or are you saying there are no buffer requirements at all? I haven’t kept up with this stuff since I stopped working in the woods over 20 years ago, so I’m not sure what the communication problem is. In other words, “tell me what I should have written instead,” as I suggested. It still looks to me like DEQ water temperature standards require streamside buffers in logging units in order to maintain temperatures that do not exceed required standards. Are you saying Newton’s studies are flawed and unnecessary?

        Also, it might help me and other participants on this blog if you explain what the “TMDL process” is. I’m hoping this isn’t a splitting hairs discussion. I do understand that TMDL has to do with muddy and/or polluted waters, I just don’t understand what the “process” is.

          • Andy: My point is that temperature regulations are essentially defacto buffer requirements aren’t they? If my opening sentence was so confusing, how do you figure I should have worded it? Those are the questions I’m asking you. (Seriously, though, thanks for the links — Wait! I’m serious about the questions, too.)

      • Andy

        Unless I am badly out of touch, the TMDL process is not required at the federal level. As I recollect, Congress killed it in the ’90s when the EPA attempted to make it law.

        Are you saying that it is an Oregon requirement?

        • The TMDL process is a requirement the Clean Water Act imposes on states. If a state fails to carry out this function, EPA must do so. Numerous successful lawsuits have been filed over the years compelling EPA to backstop states that fail to comply.

          • Andy

            Silviculture (forestry) and Agriculture are exempt at the federal level.

            From your link to the Oregon DEQ above, I could not find any reference to Forestry or Silviculture – So, since they are not listed under the DEQ departments, it doesn’t look like they have applied for or recieved any 319 funds for forestry. So, unless I have missed something, the CWA does not apply to forestry in Oregon. Note that Forest Industry appears to be only for manufacturing and therefore does not include Forestry/Silviculture.
            If the state doesn’t require TMDL permitting prior to silvicultural activities then that would seem to back me up. If it does, then I am wrong.

            See page 6 at
            –> “… CWA regulation of some sort, even though the act does not provide EPA with regulatory authority over nonpoint sources. EPA only can influence activities of nonpoint sources through use of grants and funding, such as CWA section 319, which addresses nonpoint source pollution through state-run nonpoint pollution management programs.
            Footnote (12): “While the 319 program is voluntary at the federal level, states may include regulatory components in their 319 programs.”

            See “Recapture of exemptions” at
            –> “Because some of the six exemptions involved new activities, such as minor drainage and silviculture (the clearing of forests by the timber industry), Congress recognized the need to impose some limitations on exemptions. Consequently, Congress placed the so-called recapture clause limitation on these new project exemptions. Under section 404(f)(2), such new projects would be deprived of their exemption if all of the following three characteristics could be shown:
            A discharge of dredge or fill material in the navigable waters of the United States;
            The discharge is incidental to an activity having as its purpose the bringing of an area of navigable waters into a use to which it was not previously subject, and
            Where the flow or circulation of navigable waters may be impaired or the reach of such waters may be reduced.
            To remove the exemption, all of these requirements must be fulfilled—the discharge, the project purpose of bringing an area into a use to which it was not previously subject, and the impairment or reduction of navigable waters.”
            –> Obviously, forestry, as a non-point source, has nothing to do with any of these three criteria for denying an exemption.

            • Gil, You’re confusing point-source permitting with TMDL planning. They are both parts of the Clean Water Act. Silvicultural activities generally are exempt from point-source (also called “National Pollution Discharge Elimination System” or NPDES) permitting. That’s the issue underlying the “are logging road culverts point sources?” case that went to the U.S. Supreme Court recently (no decision because the environmental plaintiffs cut and ran). TMDL is an entirely different part of the law that does involve silviculture, farming, and most everything else that goes on in a watershed. Later, I’ll post a thumbnail sketch of the TMDL process for all our policy wonk readers.

              • Andy: Thanks. I’m not a policy wonk, but I really dislike acronyms for lots of good reasons. And I like the English language, so I’m looking forward to your post on the “TMDL process.” I didn’t even know it was a policy issue, which hurts my wonk status even more. Also, thanks for spelling out what NPDES stands for.

              • Andy

                As to my confusing point source with non-point:
                How can that be? – Your statement above is that “Silvicultural activities generally are exempt from point-source”. Of course they are, because they are not point-source, they are specifically defined as non-point source and the EPA has no authority over non-point sources.

                As to my confusing TMDL permits with TMDL planning under NPDES:
                If NPDES is part of the CWA then NPDES has no impact on non-point sources since “the act does not provide EPA with regulatory authority over nonpoint sources” (to re-quote my EPA link given previously). You say: “TMDL is an entirely different part of the law that does involve silviculture, farming, and most everything else that goes on in a watershed”? I can certainly understand how you might come to that conclusion because of the way that part of the law is written but it does not retract the law in regard to “the act does not provide EPA with regulatory authority over nonpoint sources”. Is that “law” part of the CWA? Is NPDES part of the CWA?

                So the state may elect to regulate non-point sources but the EPA can not make it take action against non-point sources in a watershed with excess TMDL’s. So again, a state has the option to regulate non-point sources but the state is not required by federal law to do so.

                The Supreme Court recently agreed that the EPA is the responsible party to make the decision as to what is and isn’t point-source. Since the EPA still holds that Silviculture is a non-point source – the EPA, under the CWA, has no authority over silviculture (non-point) sources. It seems awfully plain to me – no ifs, no ands, no buts.

                End of discussion until you can give me an authoritative link that shows me where I am wrong.

  9. Any fish bios out there? And why do we see people fishing in open fields in scotland? Because it is pretty freaking cold up there ans stream temps matter a lot less in a place that sees rather little solar heat. We find the same thing at higher elevations in places like yellowstone where it gets pretty cold at night. Shade matters a lot less there but in tribs like the john day, it matters greatly

    I am aware of this paradox but not a surprise even to some avidly anti logging fish bios, Higher temps can result in higher productivity benefiting fish much of the year. But the key issue is the 8 week window in summer months when stream temps can become the single largest influence on salmonid survival. During that period at midday, we find fish prefer cold water pockets and cooler streams, most often densely shaded and/pr fed by cool groundwater.

    And there is plenty of good data out there on how higher stream temps impact salmonids.

    As for the rest of the year, I imagine that shade matters little.

    • Thanks, Greg: It’s why I pointed out that: “Their ability to swim to more favorable conditions during these changes should not be discounted.” Same reasons people go indoors with air conditioning when it gets too hot outside — or head for the shade or a breeze or a swimming pool. Just because things get too warm where a thermometer might be, doesn’t necessarily mean that fish are affected — they just swim to someplace more comfortable. Or die, if more comfortable options aren’t available. Just like people.

      • Yeah it seems like a mosaic of habitats might be optimal but that shade can be hard to find, and how far do they need to swim to find it? And once a stream heats up, shade will do very little to cool it.

        • Hi Greg: As a dedicated former creek fisherman, fish usually only need to swim to the other side of the creek to find shade — unless it’s high noon. Or float downstream to a deeper (cooler) hole. Or under a rock. And like Newton points out, streams cool rapidly within a short distance, and completely at night. That is why 24-hour resilience is such an important factor — night is always cooler than day.

    • Greg

      I don’t know if you are ranting or what, but my comment about Scotland was “Pictures of people fishing in places like Scotland always seemed to show them fishing in open fields. The perplexity is gone”. Newton’s whole article is about stream temps and their impact on salmonoids and Bob’s extracts from Newton’s works removed my perplexity.

      In addition, I think that you’ll see that I commented about high temps when I said “… southern US trout fisherman. Obviously temperatures down here often push the upper limits so more stream cover is very important …” Our window is more like 5 months in those rare places where we have trout in streams rather than in dam tailraces.

      Are we on the same page or are you still perplexed about my former perplexity? 🙂

  10. Some of you have mentioned the importance of large woody debris. Also critical to salmon for spawning: the stream bed itself — in particular, the right size of gravel or cobble. I recall reading that streams in watersheds dominated by old-growth stands have, in general, less gravel/cobble than streams in younger forests. Also, landslides are a key disturbance — without an occasional landslide, the gravel/cobble eventually washes away or is buried under sine sediment. So, I suggest that stream geology is important, too.

  11. I sent a link of this discussion to Dan Botkin and got this reply:

    Thanks for sending this. It is very interesting and you make a lot of valuable points, and the history of ideas and citations are useful to me. I would prefer to say that “Why Salmon Like Ecological Succession,” because, as you know, it is a variety of stages that provide all the qualities that salmon like. So on a single stream it is fine to have some clear-cut patches, some old-growth patches, and especially some stands of alder to provide nitrogen, and so forth. Stepping back, I think we need to get across to our colleagues and the public that nature is dynamic, and the reason life persists is that dynamism. These days I see scientists writing about the “instability” of nature, as if “stability” were the correct state, back to the balance of nature. I now make it a point to mention that an airplane wing that was always at its “equilibrium” and did not flex would break and the plane would crash. It is the flexibility, the dynamism, that allows the plane to fly.

    But this is a good article and I’m putting a note about it on Twitter and have downloaded it.

    I thought Mike Newton would enjoy these insights, and he responded:

    Before going too far on this, the one thing I would change in your essay is that Botkin is right, in that clearcuts are great, but there needs to be several times as much of stream length in buffered riparian ground at least 40 feet wide, sunny side. Idea there is that keeping shadows on the water 9AM to 5 PM prevents almost any warming, allows fair productivity, and also allows buffering trees to fall across the stream with winter storms. Those south sided buffers are not as productive as complete clearcuts, but they are productive and can make up a good share of stream length without warming it. Lots of diffuse light, not much radiant energy. You can do the math, figure the solar arc and note that these allow the same level of direct radiant energy for warming as the two-sided buffers, but provide a lot more diffuse light. You can find that in our Zwieniecki and Newton, 1999, Newton and Cole, 2013 papers as well as the in-press paper that really analyzes the radiation loads I detail; sorry that is not available at the moment. To be available shortly.

    I think these are excellent comments by well recognized scientists who are experts on these topics. This shows, to me anyway, another real value of blog posting — the subsequent capability to distribute new documents and related discussions with a simple emailed link. A new type of peer review at its finest.

    Other thoughts?

    • problem is how to set up the mosaic, as I noted before, once a stream heats up, even a very well shaded buffer downstream will not cool it,

      Although less important in some larger tribs, many if not most large pools are associated with large wood on small and medium streams in forested areas. We have decent documentation of loss of large pools since 1930s in some areas, hence so much fisheries restoration has involved bringing large wood back into those systems. I am dubious as to how well we can accomplish this since it is hard to replicate nature.

      But in eastern Oregon with many open areas and a lot less wood, I think the focus on wood was often misplaced.

      • Greg: Newton’s work shows that streams actually cool down fairly quickly after leaving warmer areas. Also, they always cool down at night. Plus, salmonids are resilient and can take fairly warm temperatures for a while, so long as they cool down periodically — I’m assuming night has something to do with that, too. I think Newton’s general formula offers some pretty good guidelines for achieving and maintaining desired temperature conditions.

        Total agreement on the eastern Oregon streams. And, once again, I personally prefer beaver to large chunks of wood when it comes to impounding small streams. Lots and lots of wasted money and well-intended volunteer hours in those regards, in my opinion.

        • I’ve done a lot of salmonid spawning ground surveys in coastal river basins of Oregon, and every time I run into a stream segment impacted by beaver, there is usually a few hundred feet to a quarter mile of fine sediment above the dams, completely unusable by adult salmonids for spawning. Large woody debris by contrast tends to trap cobble of spawning size behind it. Mind you, these surveys are “snapshots” of stream conditions, and it’s always possible that when the beaver dam finally blows out, all the fine sediment washes away and there’s pristine spawning gravel below. In the short term it does nothing good for spawning, though.

  12. How does water temperature react to dew point temperature? What is the vertical temperature gradient in a pool? What is the three dimensional flow of water at an escarpment or water fall or steeper gradient that accelerates the water? Does only the top layer flow? Bottom layers are displaced only if the replacing water is denser or turbulent??? Question, not statement of fact.
    For dams with aferbays, what is the reason for the afterbay? Control water seepage in toe drains? Warm the water for agricultural use? Both seepage control and warming?

    • Hi Dick:

      In response to these specific questions, I suggest you read some of the literature cited here and linked to PDF files whenever possible. I know some of the answers are in those sources, but I’m also certain that a few of your questions cannot be answered by the described methodologies. Also, I’m not sure what value some of these questions might have, even if they could be answered. Care to clarify the relevance of these questions, given the current research?


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