Oregon Oak: An Underdog Making A Comeback
I think we can all relate to feeling like sometimes life is just so busy that there isn’t time to sit down and read a book from cover to cover; which is why it was so nice to come across this book review by Neil Schroeder. His article beautifully summarizes “The Nature of Oaks,” and reminds us just how significant our local Oregon white oak is to the Pacific Northwest.
Without this species, numerous animals and insects would starve, our regions ability to capture and store carbon would be reduced, and the world would be that much less beautiful. To be seeing loss in the range of 97% of the western Oaks is deplorable, and we all have to start to do better about caring for this vital element to our ecosystem.
An important take away I received from this brief read, was that there is a way to reverse this deforestation, maybe not entirely, but with a fresh set of eye’s to recognize this valuable resource, we can begin to reset people’s preconceived notions about oak and all of it’s potential.
"The Nature of Oaks" by Douglas W. Tallamy, Timber Press 2021
Book review by Neil Schroeder
I have often wondered why in our Oregon, where the Douglas Fir is king in so many ways, there is so much emphasis on “Oak Savannahs”. The USDA-NRCS and soil and water districts and other consultants across the state help us find money to plant Oregon White Oak, a tree that has a small market value when compared with Doug Fir, Western Hemlock, Western Red Cedar and even Red Alder.
“The Nature of Oaks” by Douglas W. Tallamy has managed to wake me up in several ways and now I wish I had listened and started planting Quercus many years ago. Surprisingly, we even had a consultant tell us “Oak won’t grow here.” This was said when we were asking about what to grow in our lowland restoration project. That person is no longer a resident of Oregon, and we now find oak seedlings growing within a few feet of where that statement was made!
Douglas Tallamy is full of absolutely amazing oak, insect, and avian knowledge. He states that oaks play a central role in our ecosystem and in the ecosystems of the Northern Hemisphere the world over. This is because they provide habitat for more animal and insect species than any other forest tree.
Most alarming is that given their tremendous importance in the world’s ecological sustainability, the percentage of oaks in US Eastern forests from pre-European settlement to today has dropped from 55% to 25% today. The Oregon White Oak, Quercus garryana, has lost 97% of its habitat in the last 200 years. No wonder there is great emphasis on planting oak savannahs!
Tallamy says a single oak tree in its life span may drop up to 3 million acorns which serve as a lifeline to countless creatures including dozens of bird species, rodents, bears, and countless insects. He and his students have confirmed that oaks support more forms of life and more fascinating interactions than any other tree genus in North America.
You may have read that the American Chestnut nearly disappeared from forests in the Northeastern U.S. due to the introduction of chestnut blight from Asia. If it had not been for the healthy supply of acorns many animal and insect species would have disappeared along with the chestnut. Even so, over 430 species of birds are now considered at risk for extinction due to the loss of habitat.
About 75% of the insect food required by birds and other animals is produced by just a few plant genera. These plants are KEYSTONE plants which means that without these trees life support for many insects and other species would disappear. The author quotes 511 species of moths, butterflies and therefore their caterpillars, depend on oaks. This is 100 more than the closest competition. Near Tallamy’s home in Pennsylvania it would be the native cherry. He says Oaks are the top life support in 84% of the counties in North America.
Oak leaf litter is incredibly important in the life span of many insects and therefore many birds and other animals. Clearing out the leaves under our trees as soon as they fall is a disaster for many insects and worms and therefore the animals that depend on them for sustenance.
Removing native plants from the landscape can have deleterious effect on migrating birds. We often bring in non-native “cultivars” into our yards. These introduced specimens may be attractive to humans but can create severe loss of food source for migrating birds. Also, when we spray to kill certain insects, we rarely kill all of them and then they are more difficult to control as the years pass. This also creates a great loss of food for our migrating and for our year-round bird species. Birds might increase their body weight 25-50% in a single day when enough insect food is available.
Here at our house we have put up bluebird boxes each year. It is fun to watch them hunt for insects over our pasture. If we sprayed for those insects we would lose the joy of watching those brilliant blue flyers.
Oaks are one of our very best tools in responsible watershed management but perhaps the most timely and critically important ecosystem service provided by oaks is Carbon Sequestration. The dense foliage, wood and roots store great quantities of the carbon from the air. They are in addition particularly valuable due to their relationship with mycorrhizal fungi. Mycorrhizae make copious amounts of carbon-rich glomalin, a highly stable glycoprotein that gives soil much of its structure and dark color. Oaks rank as among our best options for scrubbing carbon from the atmosphere and storing it safely in soil throughout the world’s temperate zones.
So, friends, plant Quercus garryana, Oregon White Oak, in every spare spot available. We can do our part for slowing climate change and save many species from extinction.