A Handbook of the World’s Conifers: Revised and Updated Edition

Farjon, A. 2017. A Handbook of the World’s Conifers (2 volumes). Revised and Updated Edition. Leiden, Netherlands: Koninklijke Brill NV. ISBN: 9789004324428

It is not often that a book about coniferous trees covers the entire collection worldwide. Most books are highly selective and omit the rarer, less known, or esoteric species. In the two volumes now available, Aljos Farjon has assembled in-depth coverage of all 615 species of conifers. Read More "A Handbook of the World’s Conifers: Revised and Updated Edition"

TREE Fund Grant/Scholarship Application Period Opening Soon

July 1, 2017 - October 1, 2017
Online applications are open during this period for:

Free TREE Fund Webinar with CEUs

“Soil Profile Rebuilding: Rehabilitating Compacted Soils”

Featuring Dr. Susan Day (Virginia Tech)

If you’ve ever faced the problem of how to grow trees in compacted, rock-hard soils left behind after urban development and construction, then this is the webinar for you. Dr. Day will teach you the secrets of Soil Profile Rebuilding (SPR), the soil rehabilitation method that allows you to remediate soils on site, has a lasting effect, and can result in as much as 84% greater canopy relative to trees in untreated soil.

  • June 21, 2017 at 12:00 pm MDT (translate to your time zone here)
  • Pre-registration is recommended (you’ll receive a reminder email the day before the program).
  • Log in HERE on June 21.
  • 1 CEU available from ISA or SAF

Thank you to Utah State University Forestry Extension and Utah Division of Forestry, Fire and State Lands for hosting this program.

Visit to see upcoming webinars and to watch past broadcasts.

Essential Pruning Techniques: Trees – Shrubs – Conifers

Brown, G.E., and T. Kirkham. 2017. Essential Pruning Techniques. Trees. Shrubs. Conifers. Portland: Timber Press. pp.404.

This is an update and revision of the classic work by George Brown first published in 1972. The new book has been expanded, updated, and beautifully illustrated by Tony Kirkham, Head of the Arboretum and Gardens at Kew, in London. Read More "Essential Pruning Techniques: Trees – Shrubs – Conifers"

How I Came to Be an Arborist: Some of My History

I am very sure many of you may have heard this story, but us older folks have been known to repeat ourselves. This is also given that in February 2018, I will have been involved in the field of arboriculture and related fields (including zoology, but that’s another story) for 70 years, when I started with the Davey Tree Expert Company. Read More "How I Came to Be an Arborist: Some of My History"

We are The PNW

Engaged Membership – Active Credential Holders – Successful and Relevant Annual Training Conference – Quality Educational Programs – Healthy and Sustainable Organization.

These guiding principles serve as key performance indicators for the Pacific Northwest ISA. As of this writing, the Board of Directors is reviewing a long-term strategic plan, something we have been remiss in formally approving for several years now. Read More "We are The PNW"

Strategic Planning Retreat Leads to Positive Changes

I’m very happy to welcome all of you to a bright green start to Summer! The result of our long and wet winter and subsequent wet spring has been thriving landscapes and natural areas throughout the Pacific Northwest. I’m proud to say that the majority of these landscapes and trees are fortunate to benefit from the world-class care provided by the arborists, tree care companies, consultants, educators, and federal/state/local urban forestry professionals of the PNW-ISA. Read More "Strategic Planning Retreat Leads to Positive Changes"

Chapter Award Nominations

The annual PNW-ISA awards will be presented during the Lynnwood ATC. Nominations are open for:

  • Arborist of the Year
  • Tree Worker of the Year
  • Volunteer of the Year

Use the new mobile-friendly online form or access the PDF version to nominate someone you know that has contributed to the community this year.

Trees for Central Washington

Washington is well known for its verdant forestlands; however, the center of our state is very different. The coulees, shrub-steppes and other high desert landscapes of central Washington are tough environments for trees. This leaves cities asking “what can I plant here?”

For purposes of this article, we are defining central Washington as Douglas, Lincoln, Adams, Franklin, Grant, Benton and Yakima counties, and similarly dry parts of adjacent counties.

The palette of trees for these counties is smaller than it is elsewhere in Washington, yet there are a great many species of ornamental trees that can thrive in central Washington cities and towns. Read More "Trees for Central Washington"

Washington DNR 2016 Forest Health Report

The Washington State Department of Natural Resources and USDA Forest Service conduct annual aerial surveys to identify, map and monitor the impacts of insect and diseases on forest lands throughout the state. Aerial survey data are verified with ground-based observations and are compared against the results of other forest health research happening throughout the state.

Survey results are compiled into an annual report called Washington’s Forest Health Highlights. This year marks the 70th anniversary of cooperative aerial survey work between the Washington Department of Natural Resources, the Oregon Department of Forestry and the USDA Forest Service.

Due to the time required to collect and analyze the survey data, then verify and publish the results, the Forest Health Highlights outlines forest health conditions observed in the previous year. Nonetheless, these reports provide critical benchmarks for the presence or absence, scope, and severity of insects, diseases and other environmental conditions that adversely affect the health of trees and forests in Washington state.

Care to know what types of insects and diseases are affecting forest lands where you live? Download a copy of the recently released Forest Health Highlights in Washington–2016

Originally published in DNR Tree Link.