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Happy OSU Master Gardener New Year!

Tithonia with butterfly
Tithonia in the October Garden

Yes, the Master Gardener program year runs from October 1st through September 30th of the following calendar year, so we are starting a new year full of fresh opportunities to educate and support our community in successful and sustainable gardening practices!

With the start of a new year we reflect on the past year and send out a big shout of thanks to all of you for your dedicated service to the OSU MG Program!

Thank you Master Gardener volunteers for your contribution to our public service mission!

Shelley displays her log sheet
Shelley submits her MG log sheet

Thanks for the Logs!
Many thanks to all of you who sent in your volunteer log sheets!  We have been marveling at your dedicated service and the good seeds and deeds you have been sowing throughout the three counties!  Thank you for sharing your passion for gardening and education!

There is still time to submit your Volunteer Log!

For those of you, who have not submitted your volunteer log sheets, please send in your hours by Friday, October 6th.

We need all logs by that date to allow time to order new Master Gardener badges for those finishing their MG training and have enough 2018 stickers for Veterans and trainees alike. Plus, we want to include your generous service contributions in the report sent to the state MG Program, which in turn is submitted to Oregon State University!   Help us to really make our metro-area MG Program shine.

Signed, Sealed and Delivered!
Remember every October a Conditions of Volunteer Service form needs to be signed, sealed and delivered in order to remain an active OSU Master Gardener.  You can mail your signed form via snail mail to 200 Warner-Milne Road, Oregon City, OR 97045 or email them to

Get all the details on how to Maintain your ‘active Master Gardener status (both Veterans and 2017 trainees) and the forms you need to keep ‘Current’ standing in the Volunteer Portal.

Expand your Garden Education at the Fall MG Recertification Training

Sam Chan standing next to body of water
Photo courtesy of Sam Chan

Fall MG Recertification Training

Saturday, October 28, 8:00am to 3:30pm, at

Clackamas Community College, Gregory Forum Building.

19600 South Molalla Avenue, Oregon City, OR 97045

This annual event is a day-long continuing education opportunity.

Earn 6 hours of continuing education/recertification credit for 2018 by attending.  Veteran MGs and “new” Veterans who trained in 2017 need 10 hours of recertification training annually to retain status as an ‘Active’ OSU Master Gardener.  Fall Recertification is a great way to earn 6 hours of credit for 2018.

We have a stellar line-up of speakers.  This year’s presenters all bring their wealth of experience from their work with OSU Extension Service.

  • Water to Sustain our Oregon Lifestyle with Sam Chan
  • A Vital Partnership: OSU MG Program and OMGA Chapters with Joy Jones
  • Integrated Pest Management for Vegetables with Weston Miller
  • Diagnostics and Answering Questions as a Master Gardener with Brooke Edwards Ph.D.

Fall MG Recertification is also when we take the time to congratulate and cheer-on the new 2017 Class of Master Gardeners who have successfully completed their training requirements.  Weston will present the new class to their fellow Veteran Master Gardeners between 11:25am and 12noon.

The event is free to all Master Gardeners both Veterans and those finishing their 2017 training year.

Bring a snack to share on the community table and your own sack lunch.

More Continuing Education Opportunities

Webinar: Who’s Eating the Leaves?
Penn State Extension Community Forestry Management Monthly Webinar Series
Tuesday, October 17, 2017, 12 PM – 1 PM (Eastern Time)

This presentation will teach you to use signs and symptoms of tree damage to identify plant pests.   We will also talk about strategies to prevent or manage these pests.

Presented by: Ruth Benner, Penn State Extension
Where: Webinar at
Cost:  Free
1 Hour credit for Recertification/Continuing Education Credit.
Also counts as One Continuing Education Credit for Landscape Architects; Society of American Foresters (CFEs); and PLNA  Certified Horticulturalist (PCH) will be offered to attendees. One CEU for International Society of Arboriculture Certified Arborists will be awarded with 80% or higher score on webinar quiz. Certificates of attendance will be provided after the program.

Use the link above to access the webinar room starting 15 minutes prior to the webinar start time. Enter the webinar as a guest by typing your name in the name box and click the “Enter Room” button.

For more information contact Scott Sjolander at 814-350-7749 or

OSU Advance MG Webinar Recordings

Brown Marmorated Stink Bug
Brown Marmorated Stink Bug
Image source: Oregon State University

Each of the following Webinars count for 1 hour Recertification Credit

2018 OSU Master Gardener Training –  Spread the Word!

Master Gardener Training Class Students and Instructor Jane Collier
Master Gardener Training Class led by Jane Collier

Some of you have said you have found your tribe, have nurtured a long-time passion or have expanded your garden knowledge through the Master Gardener training.  Help spread the word about the MG training program and let your interested friends, family and colleagues know that registration for the 2018 Master Gardener training will open in early November.

Please direct interested individuals to our Metro Master Gardener Website to sign-up to receive a notification when registration opens.

Once again, training classes will be held in Washington (Tuesdays), Clackamas (Thursdays), and Multnomah (Fridays) counties.  Training will start the first full week in February (February 6, 8, and 9).  We have a terrific slate of presenters with a few new subjects added to the in-class training (Berries and Plant ID).  Instructors will also be incorporating some great interactive components into their presentations.  So be sure to catch a few of the classes.  Remember MG Training Classes count for Veteran Recertification credit.  3 hours credit for each AM or PM session attended.

We Keep the Public In-the-Know with Great Garden Tips for the Fall

Weston and Monica Maggio with timely fall garden tips:

Master Gardeners Growing Their Communities!

Master Gardeners at Jenkins Estate Open House
MGs at Jenkins Estate Open House. Photo: Sue Ryburn
Frank teaching at McLoughlin Elementary
Frank Wille, Teaching at McLoughlin Elementary.
Master Gardener Margo preparing garden bed at Jenkins Estate
Margo preparing garden bed at Jenkins Estate

Stock your Library and pick-up some MG Garden Apparel!

Books, a tote bag, and t-shirt
Books, totes, and t-shirts!

Fall MG Recertification (Saturday, October 28th) is also an opportunity to stock up on gardening books for the winter (all at a discounted price from Timber Press), purchase a stylish canvas, garden tote, a Master Gardener t-shirt, row cover for your garden or any of the other great items that metro-area Chapters will have available for sale at our Fall Recertification training.

The Oregon Master Gardeners Association – Read the latest news!

Logo of the OMGA

Did you know all metro-area Chapters (Clackamas, Multnomah and Washington Counties) are under the umbrella of the Oregon Master Gardeners Association?

The Oregon Master Gardener™ Association is a statewide, 501(c)(3) non-profit organization whose purpose is to enhance and support the OSU Master Gardener™ program. The county Master Gardener chapters together make up the state association.

The OMGA governing body is comprised of representatives of each of the 23 county chapters, as well as state officers. As of 2016, the OMGA was serving over 3500 members throughout the state. Quarterly OMGA meetings are held at various locations around the state.

For the latest news from the OMGA check out the Gardener’s Pen newsletter.  The September issue is available now!

Horticultural Updates

By Margaret Bayne, OSU Extension Staff-retired, OSU Master Gardener

October 2017

 “A Gardener’s Primer to Mycorrhizae: Understanding How They Work and Learning How to Protect Them,” a great new publication from WSU’s

Mycorrhizae. Photo: WSU

Dr. Linda Chalker-Scott.  “Mycorrhizae are symbiotic associations between many plants and the beneficial fungi that colonize their roots. Gardeners are often unaware of these relationships and may inadvertently injure or kill the beneficial fungi through common gardening activities. This publication will help home gardeners understand the benefits of mycorrhizae and explain how to enhance their presence in landscapes and gardens.”(Linda Chalker-Scott, Publication FS269E, WSU)

Physiological Effects of Smoke Exposure on Deciduous and Conifer Tree Species.” There is not a lot of information on how the smoke from the recent fires will affect our plants, but here is an interesting study discussing how smoke affects forest trees. (W. John Calder, Greg Lifferth, Max A. Moritz, and Samuel B. St. Clair; International Journal of Forestry Research)

Tell little girls that it is never too early to learn about bugs! “An 8-Year-Old Bullied For Her Love of Bugs Just Got Her First Scientific Publication.” (Signe Dean,

President’s Clematis. Photo: OSU

Clematis put on a special show in the garden as they climb up trellises and trees unfurling large, lusciously colored flowers! These garden favorites need a little special handling at the start but once established clematis grow and flower year after year. (Kym Pokorny, OSU)

Did you know the first space travelers were seeds? Learn what scientists are up to now. (Gina Riggio, U of Arkansas;

24 Ways to Kill a Tree! (What you shouldn’t do) and 24 ways to NOT kill a tree (what you should do). “Few residential trees die of “old age.” Mechanical damage and improper tree care kill more trees than any insects or diseases.” (Bonnie Appleton, Publication 430-210, Virginia Cooperative Extension)

Watch the five finalist videos in the 2017 “YouTube Your Entomology” contest:  (

Can You Pick the Bees Out of an Insect Lineup?  Take the quiz and learn more! (Joanna Klein,

“Tolkien’s Plant Passion Moves Botanist to Create Guide to Middle Earththe retired botany professor spent years cataloging every plant that appeared in his writing, eventually compiling a list of 141 different species. He teamed up with his son, Graham, a professional illustrator. And together, they embarked on quest to transform that list into a botanical guide to Middle Earth.” (David Fuchs,

Did you know that referring to our North American representatives as ‘asters’ is no longer taxonomically accurate? Learn why from the article,

Aster. Photo: OSU

How North America Lost its Asters.” (

Insects have much better vision and can see in far greater detail than previously thought, a new study from the University of Sheffield has revealed.” (, University of Sheffield)

“These Five “Witness Trees” Were Present at Key Moments in America’s History. These still standing trees are a living testament to our country’s tragic past.” (Mike Yessis,

Natter’s Notes:
Pear Trellis Rust, a new disease

Jean R. Natter, OSU Master Gardener

Recently, Pear Trellis Rust (Gymnosporangium sabinae) became the newest contributor to this hodge-podge-let’s-try-everything year. During 2016, the first case of pear trellis rust was reported in the northern section of the Willamette Valley, that on a Bartlett pear growing in Milwaukie, Clackamas County. (See “Pear Trellis Rust: First Report in Oregon” Metro MG Newsletter, January 2016; Then, in mid-September 2017, an inquiry about a pear leaf problem in Multnomah County was submitted to Ask an Expert. [Fig 1; Fig 2] Yes, it’s another fruiting pear tree infected with trellis rust. It seems that gardeners are beginning to recognize this newcomer.

“Symptoms [of trellis rust] on pear begin as yellowish-orange leaf spots early in the season. Young fruit and twigs can also be infected. Leaf spots can become bright reddish orange during the summer. By mid-summer, tiny black dots (pycnia) appear in the center of the leaf spots.” [Fig 3] By late summer, brown, blister-like swellings form on the lower leaf surface just beneath the leaf spots. This is followed by the development of acorn-shaped structures (aecia) with open, trellis-like sides that give this disease its common name. (Fig 4) Aeciospores produced within the aecia are wind-blown to susceptible juniper hosts where they can cause infections on young shoots. These spores are released from late summer until leaf drop.” (“Pear Trellis Rust, Gymnosporangium sabinae” (

Signs on affected alternate host junipers are difficult to detect. During wet weather in spring, look for swollen areas on branches which exude orange jelly-like horns.

Differentiate Trellis Rust from Pacific Coast Pear Rust

Trellis Rust is quite different from the widespread Pacific Coast Pear Rust you’ve likely seen every spring on Amelanchier (shadbush; serviceberry) and pears.

Pacific Coast Pear Rust infects both Asian and European pears.  And, as is common with rusts, it also has an alternate host. During spring, host incense cedars (Calocedrus decurrens) are recognized by the bright orange jelly-like globs on the foliage. On pears, the bright orange, powdery spores erupt on fruits, flowers, leaves, and twigs, often deforming them. [Fig 5; Fig 6] Management includes removing nearby hosts. A home-use spray is available for ornamental pears but not edible pears. (Keep current with the PNW Disease Management Handbook.)

Management strategies for trellis rust                             

Minimizing overhead irrigation might help reduce the number of infections. But you know how Oregon springs are.  It rains! Cultural management may help decrease infection rates:

  1. Collect and discard infected leaves.
  2. If practical, remove juniper hosts from a 1000-ft radius. (The PNW Disease Handbook states “J. communis, J. horizontalis, and J. squamata are immune or highly resistant.”)
  3. No chemical remedies are available for edible pears.

Master Gardeners as First Responders

When MGs see a plant affected by a disease or insect, we’re required to verify our tentative diagnosis before we suggest a remedy. So, here’s an important project for you: Help track the spread of Pear Trellis Rust.

If you suspect pear trellis rust while volunteering at the MG Offices or elsewhere in the metro counties, request images and/or samples. Take pictures and jot down a history with at least these few facts, if known: the name and age of the pear; when the client first detected the problem; also, in which town the tree grows. Next, email the images and history to me ( After I verify your tentative diagnosis, I will notify both you and the pathologist.

Image of Pear trellis rust
Fig 1: Pear trellis rust (Gymnosporangium sabinae) on the top leaf surface of edible pear tree; Multnomah County, OR. (Client image; 2017-09)

Fig 2: Pear trellis rust (Gymnosporangium sabinae) on the reverse of a leaf from an edible pear tree; Multnomah County, OR. (Client image; 2017-09)

Pear trellis rust
Fig 3: Pycnia (the black dots) of pear trellis rust on the upper leaf surface are involved in development of infectious structures on the underside. Bartlett pear tree; Milwaukie, Clackamas County, OR. (R. Frick-Wright; 2017-09)

Click the link below for a PDF containing the above text and all the images.

Pear Trellis Rust PDF


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Natter’s Notes: Heat Stress

Jean R. Natter, OSU Master Gardener

September 2017

This has been an interesting year as far as plant problems go. The past winter was colder than usual; this spring was wetter than usual; this summer hotter and drier than usual; and, oh yes, we had a total solar eclipse (2017-08-21) even as I was writing this. Then, too, in spite of the plentiful rainfall this past winter and spring, established trees in forests and landscapes are dying from consecutive years of drought.

For the most part, causal agents of plant problems are abiotic, caused by naturally-occurring adverse environmental factors, also the garden’s care-takers, John and/or Jane Doe. So, when clients ask which disease afflicts their plants, we have a lot to consider. We need a detailed history of what occurred and when, including pre-plant preparations as well as follow-up maintenance.

Just how plants react to high temperatures depends upon numerous factors, among them the extent and duration of the heat; the relative humidity; wind conditions; soil moisture content; the kind of plant, its age, site, and general status before the heat hit. (Phew! That’s a lot to consider.) Sometimes leaves are only damaged superficially.  Other times, tissues die. Tissue survival is most likely when the plant is fully hydrated well before the heat hits. If heat is predicted, water the night before or early morning, between 2 and 6 AM.

One good thing about the recent heat waves, the accompanying low humidity has helped limit common leaf diseases. Well, except for powdery mildew, the fungus that creates a whitish film on the leaf surface. If that’s the case, recall that most fungicides are preventive and must be applied at the very first sign of disease, long before the leaf is snowy white.

Accurately diagnosing heat damage relies, in part, upon how well you “read” the signs and symptoms. It’s a skill that requires time to develop. (You know the old saw: Practice, practice, practice.)

Let’s take a look at how heat damage may be expressed, especially on leaves, since that’s often the only thing a client submits for diagnosis.

Young dogwood (Cornus sp.), probably about 2 years old, in a commercial landscape. (Fig 1) Exposure to bright sunlight damaged superficial tissues, killed the chlorophyll (green), revealing the underlying anthocyanins (red pigments), resulting in a reddened sheen on only the most exposed leaves.  The somewhat shaded leaves retain excellent green color.

Signs of heat stress on dogwood leaves
Fig 1 – Superficial heat damage to dogwood leaves (Cornus sp.) which killed the green pigments near the leaf surface, thereby revealing the underlying red pigments. (J.R. Natter; 2017-08

Vine maple leaf with dry, brown edges, evidence of acute water shortage to the shrub. (Fig 2) Sudden heat exposure to a 19-year-old shrub damaged many leaves in a wide swath across the shrub. Affected leaves were tan and shriveled while others only had dry edges. Client wondered if the tree was at the end of its life span. The Ask an Expert response, said essentially this: It’s the recent heat. (Client image; 2017-08) Click image for larger view.

Vine maple leaves suffering from heat stress
Fig 2 – Vine maple leaves, damaged by heat and sunlight. Owner asked if the 19-year-old tree had a disease. Another vine maple, planted at the same time, was fine. (Client image submitted to Ask an Expert; 2017-08)

Hosta, exposed to sudden and extreme heat, accompanied by low humidity. (Fig 3) The most severely damaged tissue at the right edge of the leaf, outlined by a zone of white tissue, still retains normal color. This kind of damage can develop in susceptible plants even if they’re in full shade. (J.R. Natter; 2017-06-24)

Heat Stress on Hosta plant
Fig 3 – Hosta leaf, damaged in less than a day, by searing heat and low humidity that dried the tissue so rapidly it retained its normal color. The crisp, dry zone at the periphery is separated from healthy tissue by a narrow white zone. (J.R. Natter; 2017-06)

Click link below for PDF with additional information and images:

2017-09 Heat stress_Natter’s_Notes

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Where but in a garden do summer hours pass so quickly?  – Anonymous

Summer greetings!  We hope your gardens are flourishing in these high summer months.  July and August are good months to sit back, enjoy your garden, and of course spend some time wearing your volunteer hat as an OSU Master Gardener!


Phones are ringing!  Questions are flying into the Master Gardener phone clinics via email, phone calls, and visitors to our offices.  This is a great time to expand your knowledge, collaborating with other MGs as you research and advise gardeners regarding their gardening conundrums.  Sign-up on CERVIS or contact a phone coordinator.

Clackamas County Phones, Jean Bremer, 503-655-8631
Multnomah County Phones, Susan Marcus, 503-703-4937
Washington County Phones, David Butt, 503-645-5769

Farmer’s Markets are busy and vibrant with a bounty of summer vegetables and fruits, plus lots of inquiring minds seeking answers to their garden questions.  Each market has its own special qualities.  Discover those unique traits by volunteering at a few farmers markets new to you.  Grab an open slot on CERVIS  Don’t despair if market schedules appear full.  Check back often as schedules change and openings arise throughout the summer.  Let a clinic coordinator know you if you are willing to serve as a substitute for last minute cancellations at your favorite market.

Summer Farmer’s Markets:  Beaverton – Gresham – Hillsdale – King – Lake Oswego – Lents – Milwaukie – Oregon City – Sherwood – Tigard



Oregon and County Fair FUN!

If you want a big dose of summer fun, sign-up for an MG Clinic table at one of the county fairs or the Oregon State Fair.  Give sage (OSU proven), garden advice to fair visitors and take a bit of time, before and after your shift, to grab some shaved ice and check out the fair competitions whether it is honey products, the biggest homegrown fruits and veggies, or the best home brew or chocolate layer cake!  Sign-up on CERVIS to grab a shift now!  Admission passes and instructions provided to all fair volunteers.

Clackamas County Fair, August 15 – 19 (Tuesday – Saturday). MGs are in a prime location at the Clackamas County Fair with our clinic table right by the entertainment stage, lovely display garden and plant sale. Join-in!   Sign-up on CERVIS or contact coordinator Jane Collier:, 503-266-1191.

Washington County Fair, July 27 – 30 (Thursday – Sunday). Nestled right next to the demonstration gardens is the perfect location for the MG clinic. This area of the fairgrounds owes its planning and attractive appearance to the Washington County Master Gardeners and is a popular stop for fairgoers.  Yes, MGs have bragging rights for this beautiful feature of the fair grounds.  Come see it!  Sign up on CERVIS or contact Margery Brunello: or 973-699-2304

Oregon State Fair, September 1-2. For the ultimate fair experience, take a quick jaunt to Salem for the Oregon State Fair.  Master Gardeners from around the state host the OSU Extension Master Gardener Clinic.  Our Metro MG program does the honors on Friday and Saturday, September 1st and 2nd. Don’t miss this festive state celebration! Sign-up on CERVIS or email Jordis Yost, and ask for a morning, afternoon, or evening shift on Friday, or Saturday.

Get Volunteering! CERVIS will get you there!

All of the OSU metro MG Program volunteer activities are available for sign-up on CERVIS, our online volunteer registration system (for Partner activities contact coordinators). Go to the “Volunteer Portal” link found on the right side of our main website page.  Then find the “CERVIS volunteer event registration” link.

When logging into CERVIS for the first time, enter your email and click on “Don’t Know password/ Reset password” to get a temporary password.

Please only sign up for events that you know that you can attend. If you need to cancel an event, please contact the clinic coordinator for a list of other volunteers interested in serving as substitutes. It is your responsibility to find a backup.

advisory group photo
MG program Manager Weston Miller providing instructions for lively group discussions about the MG program’s future outlook. Photo by: Marcia McIntyre

Moving Forward…
Master Gardeners Advise Program

An engaged and thoughtful group of 40 Master Gardeners convened on Tuesday, June 6th for a Metro Master Gardener Advisory meeting.  Using the 2014-2019 Metro Master Gardener Strategic Plan as a prompt, participants broke into three groups for a brainstorming session, offering suggestions and recommendations for the program moving toward the future.  Lively discussion ensued, with the compilation of many thoughtful and insightful suggestions.  Program staff greatly value the input and creative ideas.  These suggestions will be further explored via upcoming Master Gardener Liaison Meetings.

Master Gardener Liaison Meetings are open to all Metro Master Gardener volunteers.  Upcoming meetings:

  • Tuesday, August 8 10am to 12noon, Washington Co. (location TBA)
  • Tuesday, October 10 10am to 12noon, Clackamas Co. (location TBA)
  • Tuesday, December 12 10am to 12noon, Multnomah Co. (location TBA)

There will also be a special meeting to explore the use of technology in the Master Gardener Program following the August 8th Liaison Meeting. The technology meeting will be from 1:00pm to 3:00pm.  Look for an email invitation to the Liaison Meetings in the next couple of weeks (RSVPs required for all meetings), with details on specific locations which will rotate among the three counties.

Hands-on in Demonstration Gardens
Summer is a glorious time for hands-on learning in any of our ‘Partner’ demonstration gardens.  Each garden offers unique active, relevant, learning opportunities.  Contact a coordinator and dig in!

Hopkins Demonstration Forest
Frank Wille 503-342-6699

Grow-An-Extra-Row and Learning Garden’ at Clackamas Community College
Nancy Muir 503-789-697  

End of the Oregon Trail Pioneer Garden
Kathy Turner 503-630-5794

Community Demonstration Garden – SE Portland
Heidi Nichols at
Nancy Fine at

Washington County Fairplex Garden
Bob Campbell 503-691-6708

Learning Garden at Jenkins Estate
Sandy Japely 503-531-8482

International Rose Test Garden in Washington Park Photo credit:

Beautiful, historic gardens.
Consider spending time this summer in a beautiful, garden – dispensing reliable gardening information.

It is a very special year at Washington Park International Rose Test Garden.  Sign-up for a shift as the garden celebrates its Centennial year!

The Pittock Mansion is another lovely and historic setting in which to share your garden knowledge.

Sign-up for a shift via CERVIS or contact the clinic coordinators.

Log Your Hours
Thank you for your passion, energy and volunteer service educating the gardening public.  We want to be sure to have a record of all your efforts.  Here is the link you need for the forms to log your volunteer hours.  Choose from a PDF or Excel form.  All hours due by October 1, 2017.

MG Nuts and Bolts
Need a refresher on how to maintain your Master Gardener certification?  All the nuts and bolts can be found here!

Save the Date!  Saturday, October 28th FALL RECERTIFICATION!

Our annual Master Gardener Fall Recertification Training is scheduled for Saturday, October 28th, 8:00am to 3:30pm, at Clackamas Community College.  This annual event is a daylong continuing education opportunity.  Earn 6 hours of continuing education/recertification credit by attending.

A great line-up of speakers is forming.  This year’s presenters all bring their wealth of experience from their work with OSU Extension Service.  They will offer a wide range of topics to enrich the knowledge base of Master Gardeners.  They are Joy Jones, Sam Chan, Brooke Edwards and our very own Weston Miller.

The Fall Recertification day also gives us the opportunity to congratulate the new class of trainees as they step up to Veteran status after completing their volunteer requirements.  We will present trainees with their OSU Extension Service Master Gardener badges and a big shout out for successfully completing the program.