Sudden Oak Death Webinar Recordings

Did you miss the What’s Happening with Sudden Oak Death in Curry County Webinar series held on April 11 and 18th? This two-part series was recorded and can be viewed anytime. Here is a quick overview: In the first session, Sarah Navarro, USFS Regional Sudden Oak Death Pathologist, gave a general overview of sudden oak death. Sarah’s presentation covered what sudden oak death is, how it spreads, symptoms to look out for, treatment approaches and the economic impacts. Sarah also discussed the Sudden Oak Death Task Force, an incredible partnership that includes private landowners, state and federal agencies as well as nonprofits and the Oregon State University LeBoldus Lab and Extension. All who are key players in finding solutions to slow the spread of the pathogen. View the recording here: https://media.oregonstate.edu/media/t/1_0h0hoqd5

In the second session, Randy Wiese and Quinn Allen with the Oregon Department of Forestry discussed survey and sampling methods. It was interesting to hear about their work exploring the use of drones to help find infested tanoaks. Drones could really be helpful, as currently they travel to each suspected tanoaks on foot! Once a potentially infested tanoak is found, they take a small sample from beneath the bark and insert it into sterile media in a petri dish that is then sent to the lab. They then carefully sterilize their tools to avoid cross contamination with future samples. Every tree that is found and sampled is geolocated and recorded in a database. This description of the intensive field work required to find and sample trees was followed by a presentation covering lab diagnostics by Elizabeth (Biz) Stamm with the OSU LeBoldus Lab. Biz covered the multiple steps, equipment and expertise required to assess samples in order to confirm sudden oak death. Biz also showed us some nice images of Phytophthora ramorum as seen through a microscope.

Finally, Dr. Ebba Peterson, with the OSU LeBoldus Lab presented first year results and future directions of a project lead by Dr. Jared LeBoldus, looking at how loss of tanoak will impact biodiversity in SW Oregon forests. This is an important question that many folks have had in regard to effects of tanoak mortality on pollinators, wildlife habitat, and the wider interconnected ecosystem. I’m looking forward to future updates from this long term study. View the recording here: https://media.oregonstate.edu/media/t/1_ehbb39wl

New Emerald Ash Borer Publication: Alternatives to Ash in Western Oregon

By now, most of you have probably heard about the infestation of Emerald Ash Borer (EAB) in Forest Grove, Oregon. This was a significant finding as it was the first detection of EAB in Oregon. EAB has killed ash throughout the United States. Once EAB is established in an area, it is extremely difficult to control as it can fly for miles to infest new trees. In Oregon, we are particularly concerned about the fate of our Oregon Ash. Oregon Ash is an important riparian tree throughout our region and has been planted extensively in riparian restoration projects. If EAB were to become widely established in Oregon, Oregon Ash mortality would leave significant gaps in riparian areas that could then easily be filled with invasive plants. Restoration practitioners are particularly interested in what riparian species they should plant in restoration sites to avoid large-scale restoration failures if EAB were to infest the site.  Here is a practical OSU Extension publication that helps answer these questions: Alternatives to Ash in Western Oregon. https://catalog.extension.oregonstate.edu/em9396

For a general overview of Oregon Ash tree health, check out Oregon Ash: Insects, Pathogens and Tree Health. https://catalog.extension.oregonstate.edu/em9380

Believe it or not, it’s going to stop raining. In most years, it stops raining as if a faucet were turned off.  If past years are any indication of the future, we might not see any measurable precipitation from July until September. The end of the rainy season signals the start of fire season and the start of industrial fire closures for forest workers as well as regulated use fire closures for the general public. Do you know where to find information on fire restrictions affecting activities on your property?  If you are in Coos or Curry Counties, access the Coos Forest Protective Association website: https://www.coosfpa.net/  Save this website as a favorite so you can view all the great resources including Today’s Fire Danger Levels. Then navigate to the Regulated Use Proclamations an the Public Use Restriction Chart that describes which activates are prohibited as fire danger increases. Go ahead and print this chart out for your bulletin board as a quick reference during fire season. The chart also provides timing restrictions and equipment requirements for regulated activities. For example, see when (and if) you can use a chainsaw for nonindustrial use during fire season, and what firefighting tools need to be carried with each saw. The Public Use Restriction Chart also provides specific details on regulations regarding operating motorized vehicles (including motorcycles and all-terrain vehicles) during fires season. This is a great time to make sure that you have the required firefighting equipment if you plan to travel in forestlands. This includes one shovel, one axe or Pulaski, and one gallon of water or a 2.5lb or larger ABC fire extinguisher. In addition, do not forget to read the restrictions regarding mowing of dried or cured grass and cutting, grinding, and welding of metal as well as campfires. This is just a selection of restricted activities and requirements. It is a good idea to read up on the rules and understand how they relate to your activities.

Landowners engaged in industrial operations will need to refer to the Industrial Fire Closure Proclamations and associated legal requirements. Check out the nice summary of fire season requirements and links to the Oregon laws and Administrative Rules that establish the fire prevention and suppression requirements for operations. The CFPA website has contact numbers if you have any questions.

Have a safe fire season everyone!

By Norma Kline, Oregon State University Extension Forester for Coos and Curry Counties

If you live or work in southern Oregon, the dead and dying Port-Orford-cedar (Chamaecyparis lawsoniana) along Highway 101 are hard to miss. The culprit behind this widespread mortality of Port-Orford-cedar is an introduced invasive pathogen called Phytophthora lateralis. Phytophthora lateralis causes Port-Orford-cedar root disease. Phytophthora means plant destroyer in Greek and is part of a larger order of microorganisms called Oomycetes or water molds. These pathogens are related to fungi, but do not develop obvious fruiting bodies. If the genus Phytophthora sounds familiar, it is because a related pathogen called Phytophthora ramorum causes sudden oak death. Phytophthoras thrive in the moist conditions in coastal Oregon. There are many other notable Phytophthoras including Phytophthora infestans, the pathogen that causes late blight of potato and tomato.

Port-Orford-cedar root disease was first detected in nursery plants in the 1920’s and was identified in natural forests in Coos County in the 1950’s. Since that time, Port-Orford-cedar root disease has spread across much of the native range of Port-Orford-cedar. While the primary host in Oregon for Phytophthora lateralis is Port-Orford-cedar, Pacific Yew (Taxus brevifolia) can also be infested. Fortunately, the disease does not infest our other native forest species. For example, the pathogen will not spread from an infested Port-Orford-cedar to a neighboring Douglas-fir (Pseudotsuga menziesii) or Western-redcedar (Thuja plicata).

Unfortunately, Phytophthora lateralis is easily transported on muddy road building machinery or maintenance equipment and even shoes. When the pathogen is moved to a new area, it typically first infests tree roots and then progresses up to the base of the tree where it girdles and kills the tree. The pathogen then progresses from one Port-Orford-cedar to the next via interconnected roots.  A common series of events is for an infestation to start with trees at the edge of a road or driveway and then slowly spread into the adjacent forest. The disease seems to travel in waves across the landscape. 

What do you do if you observe yellow and brown foliage on a Port-Orford-cedar? First, confirm that the tree is indeed Port-Orford-cedar. Western redcedar and Port-orford-cedar can look similar from a distance. Cones, if you can find them, are the best diagnostic tool. Both Port-Orford-cedar cones and western redcedar cones are very small (about ½ inch in size). Port-Orford-cedar cones are round (Figure 1) while Western redcedar cones are shaped like a rosebud, and bend up and back towards the tree (Figure 2). The foliage and bark also have characteristic differences. Turn the foliage over to observe the “X” shape pattern on Port-Orford-cedar or the butterfly or bowtie shape distinctive of Western redcedar (Figures 3 and 4). The bark can also be helpful in differentiating between the two species; Port-Orford-cedar has thicker more fibrous bark than the finer textured bark of western redcedar.

Once you have determined that the tree in question is a Port-Orford-cedar, then Port-Orford-cedar root disease might be responsible for the observed decline and mortality. On a newly dead tree, you can investigate further by carefully using a hatchet to remove the outer bark near the base of the tree. Port-Orford-cedar root disease causes a characteristic stain on the cambium (the living tissue beneath the bark) (Figure 5). Just remember, it’s not a good idea to chop into a living tree as it can expose the tree to pathogens or insects. If you see areas of loose bark on a dead tree, you might notice insect galleries (tunnels) under the bark. In many cases, these are indications of beetles that aid in wood decomposition. These “secondary” beetles invade trees that are already dead and dying. You might also see signs of cedar bark beetles, which are also considered a secondary beetle (as they are not the primary cause of tree mortality). Cedar bark beetles are attracted to stressed cedars (such as Port-Orford-cedars stressed from root disease), and stressed junipers and redwoods. Cedar bark beetle galleries are distinctive (Figure 6).

Port-Orford-cedar root disease is difficult to treat. Some landowners choose to remove obviously infested Port-Orford-cedar as well as nearby apparently healthy Port-Orford-cedar in order to disrupt disease spread from interconnected roots. This is not likely to be effective in areas where the disease is widespread. In which case, property owners will need to assess safety and fuels hazards created by dead and dying trees. Leaving some snags (dead trees) in the landscape is beneficial for both cavity nesting birds and bats. Likewise, downed logs serve as habitat for amphibians and benefits soil structure as the logs slowly rot.

If Port-Orford-cedar root disease symptoms are caught very early in the disease progression, a homeowner might opt to have a notable Port-Orford-cedar in the home landscape treated with fungicides. Continued treatments would be required to keep the infestation in check. This approach is not likely to be practical in situations where large numbers of trees are infested. Read more about chemical treatments in the PNW handbook (see References).

Luckily there is good news. Disease resistant Port-Orford-cedar seedlings are available for landowners interested in restoring Port-Orford-cedar to the landscape. Disease resistant Port-Orford-cedar are the result of a long term and very successful breeding program at the USFS Dorena Genetic Nursery in southern Oregon. Landowners interested in planting disease resistant Port-Orford-cedar in Coos or Curry Counties should contact their extension forester (norma.kline@oregonstate.edu). Just remember that planting season in western Oregon is in the rainy winter months.

As always, use herbicides safely! Wear protective clothing and safety equipment as recommended on the label. Bathe or shower after each use. Read the pesticide label – even if you have used the pesticide before. Follow the instructions on the label (and any other directions you have). Be cautious when you apply pesticides. Know your legal responsibility as a pesticide applicator. You may be liable for injury or damage resulting from pesticide use. Use herbicides responsibly.

References

Port-Orford-Cedar Root Disease Leaflet https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5346825.pdf

PNW Handbook – Phytopthora lateralis treatment options

https://pnwhandbooks.org/plantdisease/host-disease/cedar-port-orford-chamaecyparis-lawsoniana-root-rot

By Norma Kline, Oregon State University Extension Forester for Coos and Curry Counties

As with any specialized field, forestry has its own jargon. Some terms are precise and measurable while others describe broader concepts. This article covers a group of similar sounding terms (site quality, site productivity, site index, site class) which are all used to reference how well trees grow in a given area, or site. You may have observed that trees and understory vegetation grow better on some areas on your woodland than in other areas. These differences may seem more pronounced on steep areas with shallow soils where you might see less overall vegetation and slower tree growth.  In contrast, you might see fairly lush understory vegetation and rapid tree growth in flat areas near streams. You might even notice that the two areas have different species. The moist and deep soils near streams typically support mixed conifer and hardwood species including hemlock, western redcedar and alder and understory species including ferns, salal and red elderberry. In contrast, steep slopes with shallow soils might be dominated by Douglas-fir with sparse understory species including more drought tolerant species such as manzanita and silk tassel.

By Brad Withrow-Robinson, OSU Forestry and Natural Resources Extension, Agent serving Benton, Linn, and Polk Counties

Many forest landowners are aware of the growing interest in, as well as the importance of pollinators. Pollinators include many kinds of insects, and even some birds and mammals. But the pollinators attracting most of the attention are our native bees. The Master Gardeners are great advocates of pollinator stewardship and do popular trainings on caring for mason bees and growing pollinator gardens. The potential and the need for supporting pollinators in urban/suburban settings, as well as in a larger agricultural landscape is clear. But what about all the forestlands in Oregon?

By Norma Kline, OSU Forestry Agent, Coos and Curry Counties

If you have read news articles about Sudden Oak Death (SOD) in southern Oregon’s Curry County you may be concerned that trees on your property are at risk for infection. Sudden Oak Death has killed hundreds of thousands of tanoak since it was first detected near Brookings in 2001. Why has Sudden Oak Death been so damaging to our native ecosystems? Sudden Oak Death is caused by an introduced (non-native) pathogen called Phytophthora ramorum. Phytophthora ramorum is an internationally quarantined pathogen first described in California in the mid-1990’s and remains a serious threat to forest and nursery industries. Oregon’s interagency Sudden Oak Death program actively surveys and treats infestations at the leading edge of the disease.

On June 30, 2022, emerald ash borer (EAB), an exotic beetle that infests ash trees, was discovered in Forest Grove, Oregon, marking the first confirmation of the invasive pest on the West Coast. In Oregon, the establishment of EAB could devastate whole habitat types that are dominated by Oregon ash such as ash swales and sensitive riparian zones, as well as reduce urban forest cover. This pest has proven deadly to all ash species in North America and Europe, including the native Oregon ash (Fraxinus latifolia).

Since 2020 researchers have collected data on the distribution and extent of western redcedar (WRC) dieback across the Pacific Northwest. This team effort by Christine Buhl (Oregon Department of
Forestry Entomologist), Melissa Fischer (Washington DNR Entomologist), Betsy Goodrich (US Forest Service
Pathologist), and other collaborators was funded by the U.S. Forest Service Evaluation and Monitoring Program. The project was initiated after WRC dieback symptoms were observed by landowners and forest health specialists from Oregon to western Canada. Symptoms of WRC dieback include thinning crowns, branch dieback, topkill and even mortality. Don’t confuse the normal seasonal fall dieback of older foliage with WRC dieback. Read more about WRC dieback, research, data collection and results to date in the WRC dieback story board here. Of particular interest are implications related to species selection for timber and restoration planting efforts. WRC does best in areas within the coastal fogbelt and inland areas below 4000 feet with sufficient moisture. In areas where WRC dieback is observed there may be environmental conditions causing stress to WRC including drought, heat, exposure and crowding. The authors suggest that we may be seeing a potential shift in the range of WRC depending on changing conditions.

WRC Storymap of project summary and results. Betsy Goodrich (USFS R6), Melissa Fischer (WADNR), Christine Buhl (ODF): https://tinyurl.com/WRCStorymap

By Norma Kline

Have you noticed the wide array of tools used by foresters and wondered which ones might be useful for a small landowner? The decision to purchase forestry tools will depend on a landowner’s general interest in hands-on woodland management. Basic tools to consider include a compass for orienting, a loggers tape to measure distances and a woodland stick to estimate diameter and height. Other options include a diameter tape which can easily fit in a pocket and a clinometer used for height as well as slope. If you are interested in learning more about these tools check out the extension publications below in the reference section of this article. There are also more specialized and even more expensive tools like rangefinders that use laser technology; these are handy but would likely be most cost effective for professional use.

This article discusses increment borers and how they can help assess stand growth. Increment borers are used to extract a narrow wood core from a tree. The extracted core provides a clear view of the tree’s annual growth rings. Some increment borers are quite long, up to two feet or more and are generally used to core to the center of larger trees to determine their age. These long increment borers are expensive, over $600 and are cumbersome to carry. Luckily many landowners already have a good idea of tree age from planting records or by inspecting landscape changes using historical imagery in Google Earth.

The USDA Forest Service “tax tips” publication is intend to assist forest landowners and their tax advisors in preparing their 2021 Federal income tax returns. See publications here.