Pruning and Care for Oregon Oak Trees
Oak trees are native to the Northern Hemisphere and the U.S. contains roughly 90 different species. Oak trees are prized for their strength, hardness and beauty; often used for whiskey barrels, wood flooring, and furniture. In Oregon, we have only three types of native Oaks – and it is of particular interest to tree enthusiasts and environmentalists that these trees are properly cared for in order to ensure the species population remains strong in Oregon.
Oregon Oaks – California Black, Oregon White, and Canyon Live Oak
Unsure what sort of oak tree is in your backyard? Here are some details on the most common oaks found in Oregon.
Size: Grows to 80′ tall and 3′ in diameter, but are usually smaller.
Leaves: Simple, alternate, deciduous. Pinnately lobed with 7 pointed and bristle-tipped lobes.
Fruit: Acorn with deep cap about 1″-2″ long.
Twigs: Stout with buds clustered near the tip.
Bark: Dark with irregular plates. About 1″ thick.
Distribution: California black oak is most common in California, but it is found as far north as the Umpqua Valley in Oregon.
Oregon White Oak
Size: Grows to 80′ tall and 3′ in diameter. Has a rounded crown when open-grown.
Leaves: Simple, alternate, deciduous. Pinnately lobed with 7-9 rounded lobes; lobes often irregular. 3″-6″ long and 2″-5″ wide.
Fruit: Acorn with shallow cap, about 1″ long.
Twigs: Stout with several fuzzy buds clustered at tip. Pit is star-shaped.
Bark: Grayish in color, may be shaggy or have shallow ridges and fissures.
Distribution: Oregon white oak occurs throughout the Siskiyou Mountains, but seldom ventures west of the Coast Range summit. Only along the Columbia Gorge does it venture into eastern Oregon.
Canyon Live Oak
Size: May be either a shrub up to 15′ tall or a tree to 80′ tall and 2′ in diameter.
Leaves: Two distinctive types are found on the same plant. All are simple, alternate, evergreen; 1″-4″ long. Some will have smooth edges while some are spiked like holly leaves.
Fruit: Acorn from 1/2″ – 2″ long. Cap is variable, but generally shallow.
Twigs: Slender with buds clustered at tips. Pith is star-shaped.
Bark: Grayish-brown and scaly. Only about 1” thick.
Distribution: Canyon live oak grows in the rough, dry country of southwestern Oregon and south through California. It grows along canyon bottoms or other places where it has favorable soil and moisture.
Pruning Oak Trees is a Must
Tree pruning is necessary and vital to the health, safety, and beauty of any tree – including oaks. Periodic pruning keeps trees healthy, looking great, and stronger to thwart off wind storms that could topple them over.
Sanitize the Tools
Before pruning you’ll want to sanitize your pruning tools. Sanitize tools by using either 70 percent denatured alcohol or a solution of 1 part liquid household bleach to 9 parts water. Before making
each cut, immerse the tool in the solution for 1 to 2 minutes, and wipe wood particles from the cutting surface. Bleach is corrosive to metal surfaces, so when you are finished pruning clean tools thoroughly with soap and water.
The most important things to remember when pruning are to prune at the correct time of year (usually winter) and to make your pruning cuts correctly. Here are a few useful links for learning how to prune trees.
- An Oregon Homeowners Guide to Tree Care
- How to Prune and Oregon White Oak
- Pruning Basics from Oregon State University Extension Service
Special Consideration when Pruning Oak Trees
Oak trees and Elm trees are the only trees in which a dressing should be applied to treat tree wounds. A dressing will prevent oak wilt.
Pruning can be difficult, especially with mature trees that have gone a bit too long between prunings. If that describes your tree – give us a call and let professional arborists make all the tricky decisions for you.
Photo Credits: “Quercus kelloggi” by Bureau of ReclamationUploaded to en.wikipedia by Hike395Transwikied by Dmcdevit – http://www.or.blm.gov/CSNM/Readers_Guide_page2.htm. Licensed under Public Domain via Wikimedia Commons., “Quercus garryana 3786” by Walter Siegmund (talk) – Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons., “Quercus chrysolepis 08567” by Walter Siegmund – Own work. Licensed under CC BY 2.5 via Wikimedia Commons.