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Serving small woodland owners and managers in the Willamette Valley and northwest Oregon
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Is Swiss Needle Cast still a Problem?

Wed, 01/07/2015 - 12:35pm
A Swiss Needle Cast affected tree

By Brad Withrow-Robinson, OSU Forestry & Natural Resources Extension, Benton, Linn & Polk Counties


The short answer, unfortunately is ”yes”, but the news was clearly mixed when researches and land managers gathered for the Annual Meeting of the Swiss Needle Cast Coop (SNCC) in Corvallis on December 4. They met to review progress in learning more about this native disease, how it affects trees and forests, and how to manage forests in the affected areas.

The meeting included updates on this year’s aerial survey, progress in establishing the next generation of research plots across western Oregon, the effects of thinning and other management activities on foliage retention and growth, and improvements in remote sensing and growth modeling abilities. Some of the things I picked up this year included:

  • The disease is intensifying but not expanding greatly. That is to say, we are certainly seeing more severe disease symptoms in places, but mostly within areas where it has been a problem before, and the footprint of highly affected area does not seem to be growing very dramatically. The disease was detected on over 586,000 acres in 2014, which is up significantly from 18 years earlier (131,000 acres in 1996). The main area of impact remains near the coast, generally within 25 miles, except for an active area around Mary’s Peak.
  • Thinning pre-commercially does seem to help improve needle retention, but only in the healthiest trees and in the lower part of the live crown.
  • Unlike other stressors, such as drought, it seems that SNC-weakened trees are not highly attractive to Douglas-fir beetles.


2014 Aerial Survey Map
  • A new tree ring analysis suggests that Swiss Needle Cast (SNC) seems to be periodic, and that outbreaks have occurred at roughly 30 year intervals since the mid 12th century, the time of the Renaissance.
  • The same study detected indications of SNC outbreaks in each of the plots studied from the Coast to the high Cascades. Although a small study, this suggests that SNC is everywhere that Douglas-fir is.
  • An ODF economic analysis of the impacts of SNC in Oregon looked at 10 – 70 year old forests of the Oregon Coast Range. Based on an average 20% growth reduction of Douglas-fir where the disease has be detected in the aerial surveys, they concluded that volume loses to SNC in this age class exceeds 190 million board-feet per year, with an estimated log value of $78 million/year. The economic impact to Oregon’s economy is equivalent to 2,100 jobs, representing $117 million in labor income and $10 million in income tax, and including a loss of $700,000 in harvest tax. Ouch.

So this disease continues to cause damage (albeit sub-lethal damage) across a large area of coastal Oregon where it is most severe and noticeable, but it can be found in the valley and throughout the Douglas-fir growing region. This is really not new, but researchers are concerned about new reports of disease development in the foothills of the Cascades. We saw some heavily affected stands there, outside Sweet Home earlier this year. The Cooperative Aerial Survey conducted by USFS and ODF will include the western Cascades between the Columbia River and Eugene in 2015. Find out more about the work of the Swiss Needle Cast Coop including aerial surveys and past reports at the SNCC website, and watch for a tour this spring, when symptoms are at their ugly peak, to be organized by the Linn Chapter of SWA and OSU Extension.


SNC impacts on growth

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Categories: OSU Extension Blogs

Understanding GMOs and forestry

Fri, 12/19/2014 - 12:40pm

By Amy Grotta, OSU Forestry & Natural Resources Extension – Columbia, Washington & Yamhill Counties

A sculpture of DNA among the trees. Photo credit: Aras Bilgen, Flickr Creative Commons

This week, the closest contest of last November’s election – the GMO labeling initiative – was finally put to rest after a recount.  The measure ultimately failed by a tiny margin, but it did a lot to put GMO’s into the public spotlight. Of course, the ballot measure had to do with food labeling, not trees, but it got me thinking that it might be worth looking at how GMOs relate to forestry.

What is a GMO?

In case you were not following along during election season, let’s start with a definition. A GMO is an organism whose genes have been directly altered by humans, in a laboratory, through genetic engineering within individual cells. GMO methods can be used to modify an organism’s own DNA or to insert DNA from another organism. The modified cells then are regenerated into whole organisms. Reasons for doing this might be to improve crop productivity, disease resistance, the nutritional yield of food plants, or resistance to herbicides to facilitate weed control. From the technology itself to the ways that GMO might be used in society, it quickly becomes obvious why GMOs can be very controversial.

What is not a GMO?

So, on to forestry and trees. Planting season is upon us, and if your seedlings are coming from one of the small woodlands seedling sales, or from a large commercial forest nursery, and you are planting Douglas-fir, then chances are your seedlings are advertised as “genetically improved”. Some people mistakenly think that this means that they are GMO trees, but this is not the case. For decades, we have employed traditional breeding techniques in forestry to produce seedlings that perform well. On the most basic level, this means that parent trees with desirable traits, such as drought tolerance, height growth, frost resistance, etc. are identified. Seeds or cuttings from these trees are collected and grown in a controlled area such as a seed orchard. More seed is collected from these trees, so that the desired traits can be passed on to the next generation. The “genetically improved” seedlings you plant are a product of this process, not of genetic engineering.


How might genetic engineering apply to forestry?

Chestnuts accumulated on a Portland sidewalk. Photo credit: Mike Kuniavsky, Creative Commons

The story of the American chestnut tree is a good example. The American chestnut once was a major component of forests in the eastern United States. It was a valuable timber tree and an important food source for both people and animals. But, a fungal disease, the chestnut blight, introduced in the late 19th century virtually wiped it out. Only a few hundred trees survived. (American chestnut, while not native to Oregon, was brought over and planted by pioneers. The blight is not prevalent in Oregon, so chestnuts do well here.) Many people are working to try to restore the chestnut to its native range. Besides traditional breeding for blight resistance, some researchers are experimenting with genetic engineering. They have inserted a gene from wheat that conveys resistance to blight into American chestnut trees. The researchers are also testing many other genes, mostly derived from the blight resistant Chinese chestnut.


GMO research at Oregon State

At OSU, forestry professor Steve Strauss is recognized as a leader in genetic engineering research. He does a lot of his work on poplars and eucalypts, which have potential for bioenergy feedstocks, pulp and solid wood. But, before GMO plants like these could be utilized commercially, regulatory agencies and the public will subject them to a lot of scrutiny. For example, we need to be sure that there are no unintended consequences, such as unplanned spread of the modified genes to other non-GMO plants in the environment, or on a farm. So Dr. Strauss and his cooperators do a lot of laboratory and contained field studies on the safety and risks associated with genetically engineered trees, with the focus on methods for preventing their spread until they are more fully understood.


Despite the failure of the GMO labeling initiative this year, we certainly have not seen the end of the debate around this issue. So, it’s worth understanding what genetic engineering is and is not, and what the potential benefits and risks of this technology might be. For those who want to read further, I’ll refer you to this website:

I think the bottom line (and here I probably ought to invoke a disclaimer*) is that genetic modification may eventually be a management tool, like herbicides, chainsaws, and other tools in your forestry “toolbox”. GMOs are inherently neither good nor bad. The more important questions for forest managers and for society are how, when, and for what purposes they are employed.

Of course, there was another big initiative on the ballot last November. And like GMO’s, the production of marijuana certainly has its intersections with forest ecology and management, as many people in southern Oregon might tell you. But that’s a topic for another day…

*Disclaimer: the opinions expressed on this blog are of the authors, and do not necessarily represent the position of Oregon State University as an institution.

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Categories: OSU Extension Blogs