Happy Arbor Month!

Urban & Community Forestry 2021

Lake Oswego Arbor MONTH

Arbor Day is America’s National Tree Holiday, observed on the last Friday of April to celebrate the role of trees in our lives and to promote tree planting and care. The City usually celebrates the first full week in April as Lake Oswego Arbor Week, but for the first time ever, the City Council has proclaimed the entire month of April as Lake Oswego Arbor Month. This comes following Governor Kate Brown’s state-wide proclamation of Oregon Arbor Month.   Find out more about Oregon Arbor Month at Oregon Community Trees


For 32 years, the City of Lake Oswego has earned Tree City USA (TCUSA) designation from the National Arbor Day Foundation. The TCUSA program recognizes cities for demonstrating a strong commitment to managing and caring for trees. Cities earn TCUSA status by meeting four standards: maintaining a tree board (the Parks, Recreation and Natural Resources Advisory Board), having a tree ordinance, spending a minimum $2 per capita on urban forest management, and proclaiming and celebrating Arbor Day annually. There are currently 67 TCUSA cities across Oregon. Visit www.arborday.org/programs/treecityusa/ to learn more.

The City looks forward to celebrating trees with Urban & Community Forestry Workshops, Heritage Tree Dedications, Heritage Tree Walking Tours, and other in-person events and activities in the near future. In the meantime, a variety of less formal, socially-distanced activities are being brought to you by the Parks and Recreation Department, Lake Oswego Public Library (LOPL), and Oswego Lake Watershed Council (OLWC). Details are provided below and be sure to check out the 2021 Urban & Community Forestry Newsletter.


Tree Pruning Workshop- Registration is full (CANCELLED)

Explore Our Parks

Tree Inventory Training

Be an Urban Forest Superhero

The Gnomes in Nature Hunt is Back

Soil Your Undies


Tree Pruning Workshop- Registration is full, wait-list only CANCELLED

Saturday, April 24, 10 a.m. to 12 p.m., Foothills Park Pavilion, 199 Foothills Road

Understand why, what, and how to prune to develop healthy, strong, and attractive trees and shrubs. Explore pruning types, proper cutting tools and techniques, and tree responses to pruning. This workshop is led by ISA Board Certified Master Arborist Damon Schrosk of Treecology, Inc. Pre-registration is required and capacity is limited to 20 Lake Oswego residents due to social-distancing measures. Please call 503-635-0290 or email planning@lakeoswego.city for free registration.


Explore Our Parks

Throughout Arbor Month, visit parks across the City and keep your eyes peeled for displays highlighting individual trees with fun facts and maybe a joke or two. How many can you find? When you find one, take a picture and post it on social media by tagging the City @cityoflakeoswego and using the hashtag #LOArborMonth. Go explore!


Tree Inventory Training

Oswego Lake Watershed Council (OLWC) has developed a new community science program that will train volunteers on how to measure and collect data on trees growing throughout Lake Oswego to contribute to a dataset that will provide a snapshot of the health and diversity of our urban forest. Data collected by our community will provide arborists, scientists, community members, and city planners with information about the economic and ecological benefits of our urban forest. Lake Oswego’s urban forest is comprised of an abundance of trees, so OLWC is relying on our passionate volunteer community scientists (like you!) to make this project a success.

OLWC will be hosting two online training sessions during Arbor Month:

Saturday, April 10, from 10-11:30 a.m.

Wednesday, April 14, from 5:30-7 p.m.


Training for this program will occur online (via Zoom) and registration is required in advance. Dates and times are subject to change. Please visit www.oswegowatershed.org for the most up-to-date information on the project and to register for a training session or contact OLWC Watershed Coordinator, Jack Halsey, at jack@oswegowatershed.org for additional information.


Be an Urban Forest Superhero

Protect your neighborhood trees from invasive ivy! This Arbor Month, the Oswego Lake Watershed Council (OLWC) is encouraging community members to make a difference by removing tree ivy in

their neighborhood. Being an “urban forest superhero” is hard work and we want to ensure that we recognize the efforts of our community stewards. Here’s what to do:

  1. Find out how to remove tree ivy at www.oswegowatershed.org 
  2. Please be sure you have permission from the property owner before you attack that ivy. 
  3. Take a photo of trees that you saved from ivy. 
  4. Send them our way by tagging @oswegolakewc on Facebook or Instagram by using #UrbanForestSuperhero.

OLWC is supporting the formation of Urban Forest Committees within each Lake Oswego Neighborhood Association. If you are interested in learning more about joining or helping to organize an Urban Forest committee in your neighborhood, please email Jack Halsey at jack@oswegowatershed.org.


The Gnomes in Nature Hunt is Back

The wily Stewardship Gnomes, Blossom, Greenie and Oak, will hide in three different natural area parks from April to October. Come out and find them, you may win a prize! Here’s what to do:

  • Find three gnomes in three natural park areas from April to October. 
  • Take a photo of you, your dog or anything by a gnome! 
  • Post your gnome photos on social media using the hashtag #LOparksgnomes for a chance to win your very own gnome in October.

For monthly park locations, gnome clues, and to learn more about each gnome and the City’s 460-acres of natural park areas, visit www.LO-Stewardship.org.  Read below to find out where the Stewardship

Gnomes will be hiding during Arbor Month.

April Locations:

  • Foothills Park – Wave to Bald Eagles that soar overhead as you hunt for gnomes along the Willamette River path! The three clever gnomes may peek out from trees or be near native species, like redosier dogwood and salal. Enjoy reading poetry etched on tall basalt columns near the path. Location: 199 Foothills Road 
  • River Run Park – This tucked away 7-acre natural park hosts winding trails above the Tualatin River. Cross the footbridge and pass by native species, like mock orange and pacific ninebark, as you search for gnomes. Look up in the trees for frequently seen northern flicker, osprey and red-tailed hawks! Location: 19698 River Run Drive 
  • Stevens Meadows – Our three friends in red pointy hats love this 0.6-acre natural area with sweeping views of the Stafford landscape. Follow the meadow trail and cross a footbridge as you pass by native Oregon white oaks. If you’re quiet, you may spot some black-tailed deer and brush rabbits! Location: 18600 Shirley Drive


Soil Your Undies

What happens when you bury a brand-new pair of 100% cotton underwear in your garden under 6 inches of soil, wait 60 days, and then dig them up? Now is your chance to find out! Coinciding with Earth Day and Arbor Month this April, Oswego Lake Watershed Council (OLWC) is encouraging our community to get their hands dirty and participate in the "Soil Your Undies" challenge! Find out what role healthy soil plays in creating a healthy forest. Learn about the microscopic organisms that break down organic material for food, returning vital nutrients back to the ecosystem. Join the community in a fun experiment that shows how healthy our soil in Lake Oswego is through the Soil Your Undies campaign.

  • Get to Know Your Dirt (Virtual Zoom) Workshop on Earth Day, April 22, 2021, 5:00 to 6:30 pm 
  • Soil Your Undies Kickoff on Saturday, April 24, 2021. Register to pick up materials from 10:00 am to 2:00 pm at Luscher Farm or Lake Oswego or Lakeridge High Schools. 
  • Share your results on July 7, 2021.

Visit www.oswegowatershed.org to register and for more information on this campaign. 

Learn About Trees, Wildlife and The Great Outdoors

Celebrate Arbor Month with a book!

Lake Oswego Public Library librarians have carefully compiled Arbor Month-themed book lists for all ages through our Pinterest accounts. For children, visit www.pinterest.com/lakeozyouth/arbor-day/ to find direct links to picture books, information books, and chapter books about trees for children. For adults, visit www.pinterest.com/lakeozadult/celebrate-nature/ to find direct links to e-books, e-audiobooks, and streaming videos on nature.

The Dirt on Soil

We love our trees! We love their shade, their graceful patterns against the sky and how they store carbon to combat climate change. But where would trees be without their roots? We cannot see their roots, but know they anchor the beauty towering over us.

Where does that stability come from? The soil into which the tree roots reach.

What do we know about that soil? Do we just take it for granted? It’s always there!

That soil is as important to the health of our trees as the air is to the trees making food. The air supplies the carbon for tree leaves to make the food and structural building blocks to keep the tree alive and growing. An important part of that process (known as photosynthesis) also requires water that is extracted from the soil by the tree roots. But that soil does so much more than anchor the tree and provide water—it also supplies all of the minerals and other nutrients (particularly nitrogen) trees need to live.

For many years soil scientists thought of soil as an inanimate object composed of ground up rocks. But that is only half of the story. The other half of soil is air, water and organic matter which includes a multitude of living organisms. The living, biological component of soil includes microbes, mycorrhizal fungi, insects and worms. Most of which are too small to see with the naked eye. This living component of soil is the key to healthy, fertile soil. This unseen living system breaks down the soil to supply minerals, capture nitrogen from the air, and create spaces for water and air. Without this living component, soil just doesn’t work properly.

Tree roots are an important part of this system since plants actually take some of the food they make in the form of sugars and pump it into soil to feed these organisms. This is an interactive system where the biotic components provide nutrients and plant roots provide food for these organisms. When we use pesticides and artificial fertilizers, we kill off these living organisms and destroy this interactive system. Artificial fertilizers can actually make tree roots lazy and they stop expanding and feeding the soil.

We all benefit from understanding natural systems and supporting natural processes. Get to know your dirt! Join us for Soil Your Undies activities during Arbor Month!

Related Links Attachments