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Quote of the Month — September

September 8, 2014

“…plants had to develop incredibly sensitive and complex sensory mechanisms that would let them survive in ever changing environments.”

“Just because we don’t see plants moving doesn’t mean that there’s not a very rich and dynamic world going on inside the plant.” 

~ Daniel Chamovitz, Director of the Manna Center for Plant Biosciences at Tel Aviv University and Author, What a Plant Knows

Quotes from Dr. Chamovitz have been excerpted from an interview in 2012 with Scientific American entitled, “Do Plants Think?




Coordinator’s Corner — Learn, Plant, Celebrate

September 8, 2014

Fall is a great time to celebrate, plant, and learn about trees. Whether you are a certified arborist, a planner, or a tree board member, the Annual Training Conference sponsored by the Pacific Northwest Chapter of the International Society of Arboriculture (the PNW ISA ATC), is one you won’t want to miss. The theme for this year’s ATC, held in Vancouver on September 28 – October 1, is Our Trees, Our Future.

To assure that trees are part of our future, it is important to keep abreast of new research and best management practices in tree planning, planting, care and maintenance. This conference offers an excellent opportunity to educate yourself and to meet and connect with fellow tree practitioners. It is a great time to compare notes and maybe figure out creative solutions to pressing tree-related issues.

You won’t want to miss the PNW ISA tree climbing championship on Sunday. Monday’s field day has plenty to offer those involved in field operations, and on Tuesday there are five different in-classroom “tree tracts” offering workshops that interest utility, climbing, municipal, and commercial arborists, as well as a tree tutorial tract for newcomers to the profession.

Remember: October is Urban and Community Forestry Month. Many communities in Washington hold volunteer tree planting or restoration events in celebration of trees. Is your community planning an event? Please send us the time, date, and location of your event. We’re happy to post it on our Tree Link calendar and maybe even join in the fun.

Hope to see you in Vancouver.

By Linden J. Lampman
DNR Urban and Community Forestry Program Manager

Errors and Omissions (oh no!)

September 8, 2014

Okay, we make mistakes, but we also fix them. Fortunately, WordPress (Tree Link’s electronic platform) allows us to revise and update articles after they are published.

In response to last month’s installment of “A Tree to Try — European Mountain-ash (a Rosaceae by any other name…)”, several readers wrote to Tree Link with concerns about featuring the Mountain-ash tree given its invasive nature, which the article did not mention. To correct this oversight, the article was amended to say:

“Yet, while the birds enjoy this tree, it is far less popular among Ecologists, and with good reason. The Mountain-ash does have invasive tendencies and is on the Washington Noxious Weed Control Board’s ‘monitor’ list, and on King County’s ‘weed of concern’ list. If you are to try this tree, do so sparingly and choose your planting areas wisely to limit the potential of escape into natural areas”.

That same article also referred to Mountain-ash fruits as berries, however, it was brought to our attention that berries are a specific type of fruit (which include grapes, blueberries, and currants) and that Mountain-ash have pome fruits, putting them in same category as apples, pears, and quince. The article was amended to suggest that Mountain-ash fruits are “berry-like”.

In the July edition of “A Tree to Try — Not a Purpleleaf Plum (plenty of other pleasing purple plant picks)”, the article originally promoted a cultivar of European Beech called ‘Dawyck’s Purple’, however a reader pointed out that this was a narrow-growing cultivar and correctly questioned that we intended to promote ‘Autropurpea’, a purple-leafed cultivar with a more typical Beech growth habit. The article was updated accordingly.

October is Urban and Community Forestry Month

September 8, 2014

35th ave PP plant

Autumn, when trees and forests across Washington reveal the natural magic of their fall colors, is certainly a season to celebrate trees.

Washington’s native deciduous trees, such as Bigleaf Maple, Cottonwood, Aspen, Birch, and the Western Larch, specialize in yellow fall colors, whereas our urban forests, planted with many non-native trees, paint our cities and towns with hues of orange, red, and purple that stir the human spirit.

And with plenty of moisture and crisp, cool fall weather, Autumn is a great time to plant trees.

Several communities celebrate Arbor Day in October, and yes, you can proclaim and celebrate the “tree planter’s holiday” at any time of the year. Other communities celebrate twice a year with an Arbor Day celebration in the Spring and a fall festival in the Autumn.

How will your community be celebrating Urban and Community Forestry Month?

This year for the second time, October is being officially proclaimed as “Urban and Community Forestry Month” by our Washington State Governor, Jay Inslee.

We hope you enjoy the fall weather and celebrate the season by planting and celebrating trees during the month of October.


A Tree to Try — Ponderosa Pine (a fine pine to ponder planting)

September 8, 2014

Branch structure of a mature ponderosa pine in Leavenworth, WA. Photo by Paula Dinius/WSU Chelan County Extension

Ponderosa Pine, Pinus ponderosa 

When was the last time you selected a native Washington conifer for a landscape planting? Let’s bring a few back into the landscape where appropriate*.

If you’re on board with that idea, then ponderosa pine is a fine tree to ponder planting where space is available*.

Ponderosa pines are BIG trees: the Washington State Champion Ponderosa Pine, growing near Trout Lake, Washington, in the Gifford Pinchot National Forest, is 7′ in diameter and 202′ tall! Heights of 80′-100′ and diameters less than 3′ are more common, however.

Ponderosa pine is an emblematic tree of the American West, as well it should be since it is found in every state west of the Mississippi except Alaska and Hawaii. Ponderosa pine ranges within those states, however, are scattered by changes in elevation, soil type, and soil moisture. These scattered populations have developed into slightly different varieties. Pacific ponderosa pine (P. ponderosa, var. ponderosa) is the variety typically found in Washington State.

The needles are 5-10″ long, dark olive-to-yellowish green, and are usually bundled in fascicles of three, occasionally in fascicles of two. Buds are cylindrical, red-brown in color, and less than 1″ long. Cones are oval, 3-6″ long, and often bunched together in groups of 3-5.

Mature ponderosa pine bark. Photo from

A most distinctive feature of the tree is the bark: heavily furrowed and rich black-brown on vigorous young trees, mature ponderosa pines exhibit a thick, fire-resistant bark that separates into broad, orange-colored plates–an iconic and defining characteristic of the tree. On warm days, light scents of cinnamon or vanilla may emanate from the bark, a delightful identifier.

Although ponderosa pine prefers full sun, performing best when planted in deep, well-drained loam soils, it can and does thrive in sub-optimal conditions throughout its range where soils may be rocky or sandy and where moisture is more limited. Note that, typical of pines, it will not thrive in wet, heavy, clayey soils. Pests and diseases, such as bark beetles, pitch moths, rusts, needlecast, and root rots, can thwart the health and longevity of any ponderosa pine, particularly those under stress.

photo 3

Newly planted ponderosa pine in Olympia, WA. Photo by Ben Thompson/DNR


Have we convinced you to plant a ponderosa pine where you live? Take a bit of advice from WSU Chelan County Extension Agent and ISA Certified Arborist Paula Dinius:

“The three most important things to remember about planting this tree and most other native conifers are:

  1. Make sure you have enough space
  2. Make sure you have enough space
  3. Make sure you have enough space!”*


*Lack of available planting locations that are physically large enough to accommodate the mature size of PNW native conifers is perhaps the primary reason that more of these lovely trees are not planted in urbanized Washington landscapes. Some cities are considering regulations that require larger planting spaces in development designs, while others have passed ordinances requiring percentages of trees planted to be native species. While these successes are helpful, the fact remains that many of our existing street tree planting sites, parking lot islands, and urban yards have not been designed or built to accommodate large native tree species. And that, to turn a tree cliché, is a tough nut to crack.

Does your city have conifer-friendly ordinances and policies, or is your city is considering developing them? We’d like to hear about it. Contact the DNR urban forestry program at


POLL RESULTS: Your Association with Urban Forestry

September 8, 2014

This poll was kept in place for the last two editions of Tree Link. The poll question was framed as follows:

“Which of the following most closely characterizes your experience with or exposure to urban forestry?”

Poll respondents selected one of the following statements as their answer (poll results by percentage in parentheses):

1. I am a professional Arborist or Forester (35%)

2. I work in horticulture, landscape care, or other allied profession (10%)

3. I am a Master Gardener, Tree Board member or Volunteer (15%)

4. I work in the non-profit sector and have a professional interest in urban greening (6%)

5. I work in Academia as a Professor, Researcher, Extension Agent, or Student (8%)

6. I am a professional in a different field with limited knowledge of urban trees and forests (25%)

The intent of this poll was to glean insights on readers’ exposure to urban forestry, and the results offer some interesting insights.

It is first encouraging to know that at least 25% of Tree Link readers count themselves as non-tree professionals, yet read the Tree Link for information about urban forestry in Washington. Here at DNR, we have often quipped that we should not be preaching to the choir, but rather trying to make the choir bigger. To that end, we would love your help. Please forward the Tree Link to others and encourage them to subscribe.

Second (taking liberties with interpretation given that respondents’ specific levels of familiarity with urban forestry cannot be known), it would seem that approximately 50% of our audience is relatively savvy with technical aspects of urban forestry, whereas the other 50% may be less so, give or take 10% either way to account for this assumption. In either case, this suggests that Tree Link needs to balance technical info for the pro’s with a more colloquial tone for the volunteers and non tree experts. Is Tree Link achieving that? Can we do better? Please let us know.

And for those of you who are professional horticulturalists and foresters, those of you in academia, or anyone else with an eye for technical or scientific detail, the Tree Link relies on your feedback to keep us honest. If we ever misrepresent an issue, omit information, or make a mistake, please call it to our attention for the sake of our readership and our reputation as a trusted source of information.

Thanks to all of you for investing your time to read the Tree Link.

Do you have a suggestion for Tree Link? If so, please send an email to

2014 PNW-ISA Conference Update; Register Today!

September 8, 2014

Come one, come all to the 2014 PNW-ISA Chapter’s Annual Training Conference which will be held September 27 through October 1 in Vancouver, Washington. This year’s event promises something for everyone.The conference kicks off on Saturday, September 27, with the Chapter’s tree-climbing championship at the Fort Vancouver National Historic Site. The region’s top climbers will vie for regional honors and the chance to compete in the Master’s Challenge, to be held the following day, Sunday, September 28, in the same location. Winners of the Master’s Challenge will represent the PNW Chapter at the International Tree Climbing Competition in 2015.

Also on Sunday are two Tree Academies, in-depth workshops featuring instructors with years of practical experience. This year’s Tree Academies address effective business management practices and advanced tree appraisal.

The conference Field Day takes place on Monday, September 29, in the heart of downtown Vancouver at Esther Short Park. This year’s Field Day sessions will demonstrate sparpole positioning, rope splicing, cable support systems and sonic tomography. Following the field day, attendees can relax with vendors at an evening reception complete with live music.

Tuesday’s program moves indoors, opening with a welcome by Vancouver Mayor Timothy D. Leavitt and the conference keynote address by Keith Cline, Director of Urban Forest Management in Fairfax County, Virginia. Concurrent sessions run the rest of the day in tracks dedicated to Utility, Climbing, Commercial, and Municipal arboriculture. In addition, a fifth track will feature Tree Tutorials for beginning arborists and Bi-Lingual sessions in Spanish.

The Chapter’s Annual General Meeting will be held Wednesday morning, October 1, followed by two General Sessions. Stacey Holloway presents techniques to develop good communication skills and Dr. Brian Kane discusses how pruning decisions may influence trees’ resilience to failure.

ISA CEUs are available for all sessions. AICP CMs are available to planners attending Municipal Track presentations. Other recertification credits applied for include the Tree Care Industry Association, the Washington Association of Landscape Professionals, and the Oregon Landscape Contractors Board.

For details, or to register, please visit the conference website.

See you in Vancouver!

PNW Chapter ISA logo_new

Timely Tree Tips — Fall Color or Distress Signal?

September 8, 2014
photo 1

This red maple in Olympia, WA began turning in late July and approaches peak color while other trees remain green. See additional photo this page to find out why. Photo by Ben Thompson/DNR.

Last month’s installment of Timely Tree Tips discussed the importance of proper tree watering for maintaining tree health and vigor. If you haven’t been watering your young trees this summer, then you may be noticing that autumn seems to be arriving early where you live. Early foliage color change isn’t necessarily a good thing, despite our fond associations with Mother Nature’s brilliant fall display. If your tree is screaming at you silently in shades of red, orange and brown, you may want to dig a little deeper, actually and metaphorically, to get to the ‘root’ of the issue.

Fall leaf color change and leaf drop are normal processes. Fall-color-come-early in September, August or even July (yikes!), however, is a tree’s way of waving a distress flag in hopes that you’ll notice its need for WATER! Extension articles from Oregon and Illinois explain the issue in more detail.

Red Maple street tree, Olympia, WA

Root/soil/water issues cause early fall color for this tree. Note the buried root flare (no increase in trunk size at grade), under-sized mulch ring, and dead grass (only weeds are green). Photo by Ben Thompson/DNR

Root issues can disrupt a tree’s capacity to absorb water, creating an artificial drought stress that contributes to preseason color change. Girdling roots, trees planted too deeply, root suffocation in compacted soils, or mechanical root injuries such as those from construction activities are frequent instigators of drought stress.

The best medicine for a tree flashing a colorful leaf distress signal is to apply supplemental water through the heat of summer into fall, and ensure it has a blanket of mulch to retain soil moisture. An ISA Certified Arborist may suggest other ways to help your trees regain health through pruning, root-collar excavations, soil amendments, or pest and disease treatments.




The 2015 Washington Envirothon: Urban Forestry

September 8, 2014

Urban forestry is the current issue for the 2015 Washington State Envirothon, which could be a great way to connect students, schools, and communities with urban forestry efforts statewide. Conservation districts across Washington are promoting the 2015 Washington State Envirothon to high schools around the state this coming September, and they could use your help.

The Washington State Envirothon is an annual competition in which teams compete for recognition and the opportunity to attend the North American Envirothon competition by demonstrating their knowledge of environmental science and natural resource management. The teams, each consisting of five high school students (grades 9-12), exercise their problem-solving skills in a competition centered on soils and land use, aquatic ecology, forestry, wildlife, and a current environmental issue.

Six regional competitions are hosted across the state each year, with top county winners moving on to the State Envirothon Competition. This year’s state competition was hosted at the end of May by King Conservation District at Camp Don Bosco, Carnation.

To get involved where you live, or for additional information about the Envirothon, contact 2015 Washington State Envirothon Chairperson Cindy Pierce from the Skagit Conservation District at 360-428-4313 or

The mission of the Washington State Envirothon is to provide resources for students and teachers, through education and teamwork, which promote environmental awareness, critical thinking, and active personal stewardship for the purpose of balancing the quality of life and the quality of the environment.

The Envirothon mission is accomplished by developing in young people an understanding of the principles and practices of natural resource management and ecology and the ability to deal with complex resource management decisions. The goals should be used as a guide to develop effective curricula, educational resources, and testing scenarios.

Participating in Envirothon is a fun and challenging opportunity that will open your students’ eyes to real-world problems and solution. They’ll become excited, empowered, and skilled stewards of our earth’s natural resources while making new friends across the state and seeing connections beyond their own communities. Get ready to make a difference!


Web-ucation: Links to Help You Learn

September 8, 2014

Can plants see, feel, hear, smell, communicate and think?

Check out this interview with Dr. Daniel Chamovitz, Director of the Manna Center for Plant Biosciences at Tel Aviv University and author of the 2012 publication, “What a Plant Knows”

Urban Forests provide human health benefits; Does this mean that city trees save lives?

Research conducted by the USDA Forest Service on the connections between tree mortality and human mortality has been summarized in this video at

Is your community Rain Ready?

This water conservation initiative from the Chicago area has great ideas for people and communities to resolve common stormwater issues in cities and towns.

Learn more than you ever thought possible about a broad range of invasive species.

Created by USDA-APHIS’ Identification Technology Program (ITP), ID Tools helps agency staff to quickly identify pests, including insects, diseases, harmful weeds, and more.

Oregon State University offers the first on-line graduate certificate in Urban Forestry for professionals interested in continuing education.

If you’ve ever been interested in graduate-level education but felt you didn’t have the time, now there’s an new option. Check out this online certificate program.

The National Climate Assessment was released this past May.

How will climate change affect you? Read the full report or fast forward to an overview of anticipated impacts in the Pacific Northwest.

September Calendar of Events, Activities and Opportunities

September 8, 2014

September 10: Washington Community Forestry Council meeting

When: Wednesday, September 10, 2014

Where: Finch Arboretum, Spokane

September 16-17: Meeting the Challenge: Preventing, Detecting, and Controlling Invasive Plants

When: Tuesday, September 16, 2014 and Wednesday, September 17, 2014

Where: University of Washington Botanic Gardens, Seattle

Cost: Questions regarding registration should be directed to Sasha McGuire at or (206) 685-8033

Invasive plants are a significant threat to biodiversity and ecosystem function. New introductions continue to emerge through a variety of pathways and vectors, while existing invaders continue to persist and expand their range. Changes in climate, land use, and biotic interactions present new challenges in controlling the spread of these invaders. Land managers and scientists will hear the latest information on how to effectively prevent, detect, and respond to these persistent and emerging threats. Conference presentations, both invited and contributed, will stimulate dialogue, raise new questions, and offer innovative solutions. Participants from throughout northwestern North America will contribute ideas and meet colleagues for collaboration.

September 27-28, 2014: PNW-ISA Chapter Tree Climbing Championships

When: Preliminary events take place on Saturday, September 27; the Master’s Challenge takes place on Sunday, September 28, 2014.

Where: Fort Vancouver National Historic Site, Vancouver, WA

Cost: $75 for competitors; free to the public to watch. Visit the PNW-ISA website for registration and other event information

September 28-October 1: PNW-ISA Annual Training Conference

When: Tree academies take place on Sunday, September 28, 2014; Field Day takes place at Esther Short Park on Monday, September 29, 2014; and indoor conference presentations are Tuesday, September 30, 2014 and Wednesday, October 1, 2014.

Where: Hilton Vancouver Washington, 301 W 6th St., Vancouver, WA 98660

Cost: Visit the conference website for event details, costs, and registration information

October is Urban & Community Forestry Month. How will your community be celebrating?

November 3 & 4: 50th Annual Society of Municipal Arborists’ Conference and Trade Show

When: Monday, November 3 and  Tuesday, November 4, 2014

Where: The Westin Charlotte, 601 S. College St., Charlotte, NC 28202

Cost: Visit the Society of Municipal Arborists website for more information as it is made available

November 5 & 6, 2014: Partners in Community Forestry Conference

When: Wednesday, November 5 and Thursday, November 6, 2014

Where: The Westin Charlotte, 601 S. College St., Charlotte, NC 28202

Cost: Visit the National Arbor Day Foundation’s website for more information as it is made available