Blog

Species Highlight: Oregon White Oak

June 10, 2020 By ,

There are Oregon white oak trees growing in the Willamette valley today that were growing long before European settlement of our area. The Oregon white oak in the photograph above is around 200 years old and grows at Graham Oaks Nature park in Wilsonville. The Oregon white oak (Quercus garryana) is native to Oregon and is important to the ecosystem... Read More

Shrub Pruning

May 7, 2020 By ,

The natural forests of the Pacific Northwest are characterized by several canopy layers—from the towering canopies of Douglas firs; to the under story shrubs including rhododendron and salal; down to ground-covering ferns. In the Portland area’s urban forest, shrubs grow in an astounding variety and can be kept small under the kitchen window or be allowed to grow to be... Read More

Species Highlight: Flowering Cherry

March 18, 2020 By , ,

Against the grey spring Portland sky, flowering cherry trees explode with blooms in a breathtaking spring spectacle.  The fluttering petals, bright white and pink colors, and frilly textures of the flowering cherry are noticed from a distance against the stark backdrop of mostly bare deciduous trees and dark green evergreens. All across the Portland area, flowering cherry trees bloom in... Read More

Portland Heritage Tree Program

March 9, 2020 By ,

Since 1994, the city of Portland has designated over 300 trees as heritage trees because of their significance to the city. The heritage tree designation protects the tree by requiring a permit for pruning or removing the tree. Some of the trees are considered significant due to their history or age, others due to their size or type. These citizen-nominated... Read More

Tree-Dwelling Lichen

February 10, 2020 By , ,

Lichen-covered trees are a common site in forests and backyards of the Pacific Northwest, and are most conspicuous during the wet winter months when the branches of deciduous trees are bare. Lichen are made up of a fungus and a photosynthetic partner that work together to form unique species.The fungus provides the structure of the lichen and the photosynthetic partner... Read More

Species Highlight: Douglas-fir

January 21, 2020 By ,

Douglas-fir trees grow all around us, dominating neighborhood skylines in all corners of the Portland area. The vast majority of conifers growing west of the Cascades are Douglas-firs. The Douglas-fir, Pseudotsuga menziesii, is the official state tree of Oregon due to its economic and ecological significance to our state. Douglas-fir seeds, cones, inner bark and needles are important food sources... Read More

Tree Anatomy: Nuts

November 13, 2019 By ,

At this time of year, trees across the Willamette Valley are producing a bounty of nuts. Nuts are one of the many seed adaptations of trees. The botanical definition of a nut is a dry fruit with only one seed. The seed of a true nut does not split open at maturity. Chestnuts, hazelnuts, and acorns are examples of true... Read More

Dormancy Onset In Trees

October 16, 2019 By , ,

The nights are quickly becoming longer in the northern hemisphere and the average temperatures are dropping, triggering dormancy in trees. Dormancy is a winter weather survival mechanism in which tree shoot growth is significantly reduced to protect soft tissues from freezing temperatures. In the fall, the decreasing daylight triggers the production of abscisic acid, a hormone that impedes growth. Abscisic... Read More

For The Love Of Trees Arborists Help Out At Hoyt Arboretum

September 17, 2019 By

For years, the arborists of For The Love Of Trees have volunteered their time and expertise to care for the trees of the Hoyt Arboretum. Every September, arborists from across the Portland area work together on tree care projects all over the 190 acre arboretum in an event called “Arborists in the Arboretum”. This year, For The Love Of Trees... Read More

Tree Sunburn

July 25, 2019 By , ,

The sunny, clear days of Oregon summers send us scampering for shade to protect our delicate skin from dangerous UV rays. Trees can be damaged by the sun too. The mature cherry tree seen above has a sealed sunburn wound. When the amount of direct sunlight the tree receives abruptly increases, the extra heat and radiation can damage the nutrient-exchanging... Read More