Signs of Fall

John Alyward

Autumn is a time of transition in Oregon’s high desert. The cooler days and cooler nights bring a wave of rust-red and brilliant yellow hues into this generally sage-green and dusky golden brown plant life, and everything from butterflies to elk is on the move.

Read on for more of the cyclic and seasonal natural phenomena you might observe in Oregon’s high desert in September, October and November. And, feel free to share your own observations with us! You can send them to, or, share stories and photo on social media with the hashtag #highdesertautumn.


What defines Oregon’s high desert?

What defines Oregon’s high desert?

Bounded by the Cascade Mountains to the west and the Blue Mountains to the north, Oregon’s high desert covers approximately 24,000 square miles. Annual rainfall in the high desert varies from 5 to 14 inches. The average elevation is 4,000 feet; at 9,733 feet, the summit of Steens Mountain is the highest point in Oregon’s high desert. The terrain of the high desert was mostly formed by a series of lava flows that occurred between 30 and 10 million years ago.

Sources: The Oregon Encyclopedia; Wikipedia  


Stewardship Fence Building Timelapse

Stewardship Fence Building Timelapse


Helen Harbin, ONDA Board Member

Helen Harbin, ONDA Board Member

“I connect with Oregon’s high desert through my feet, my eyes, my sense of smell, and all the things I hear. Getting out there is a whole body experience.” Supporting ONDA, Helen says, not only connects her with wild landscapes, but is also a good investment. “I felt like if I gave them $20, they might squeeze $23 out of it.”

Hiking through rabbitbrush (Ericameria nauseosa)

Jeremy Fox

Pine siskin (Spinus pinus)

Andy Wraithmell

Juniper berries

Mark Darnell

California tortoiseshell (Nymphalis californica)

Peter Pearsall via Friends of Malheur National Wildlife Refuge


Watch for yellow cottonwood trees, which may be seen for miles due to their stature as our tallest deciduous trees, along waterways and sometimes indicating old homesteads. In these riparian areas, you might also see the colorful foliage of net-leaf hackberry, choke- and bitter cherries, red-osier dogwood, and Saskatoon bushes.

In the sage lands, rabbitbrush often puts on spectacular shows of dense yellow flowers in September. Other fall color comes from late-blooming wildflowers, including the purple blooms of aster and the deep yellow blooms on goldenrod.

Among the grasses, Great Basin wild rye is turning color and its ripening seeds provide an incredibly valuable food source for a wide variety of fall birds. Sparrows especially feast on grass seeds, as do goldfinches and pine siskins, all of whom you may see in increasing numbers this month. Small insect-eating birds are busy patrolling the trees, probing the bark and buds for treats. You might encounter large groups of bush tits swarming the junipers to enjoy their now-ripe berries. I find it fascinating to try and figure out why some trees are covered in thousands of these round, blueish fruits, while other trees have none at all. Junipers have male and female trees, and some trees have, or are, both sexes. The surface of their berries provide a host medium for wild yeast, which is the bluish “dust” that coats these otherwise blue-black berries.

Butterflies can be abundant in late summer, with occasional mass eruptions and migrations, especially in the upper reaches of the canyons and on certain high points. California Tortoiseshell have been quite abundant in the higher elevations so far in 2020. Look for some great spider webs, too, which look cool when they are covered in dew or frost as fall progresses. You might even catch sight of female spiders, which can be huge this time of year, and many are quite beautifully marked.

Aspen (Populus tremuloides) on Hart Mountain

Jim Davis

Rocky Mountain elk (Cervus elaphus nelsoni)

Jim Yuskavitch via ODFW

Ferruginous hawks (Buteo regalis) in Malheur National Wildlife Refuge

Dan Streiffert

Golden eaglets (Aquila chrysaetos)

Barb Rumer


While aspens begin changing color in late September, their seasonal show is most reliable in early October. They are abundant on the high points of Hart Mountain and Steens Mountain. Since each stand of aspen may be made up of several clones, or all one huge cloned group, you can see quite a lot of color variation, from bright yellow-green to the true yellows and oranges and even rust, in a relatively small area.

The first cold nights and early snows will begin to drive mule deer, Rocky Mountain elk, and pronghorn down from the high country. Migration corridors, like long, deep canyons or river crossings, will funnel and concentrate animals and can thus be great places to watch them moving through the landscape.

Raptors also offer an amazing migratory spectacle as they move southward towards warmer climes in search of prey that will soon be hiding out under the cover of snow.

Mountain Mahogany (Cercocarpus ledifolius)

Scott Erickson


Barb Rumer

Coyotoe (Canis latrans) in the Steens Mountain Region

Shannon Phifer

Bighorn sheep (Ovis canadensis) along the Deschutes

Steve Loebner


Without summer’s dust, smoke and haze, the clear fall air can provide great long views and grand vistas, and, as the snows begin returning, these views are punctuated with snow-capped high points. It can be quite rewarding to return to one of your favorite views to catch a sunset or sunrise, or camp out and watch stars.

Mountain Mahogany trees are lovely now, offering good colors and a unique and relaxing smell to the duff—a great place to rest in the middle of the day, or to sleep out underneath. Lichens have many great colors and some amazing, even otherworldly, forms and are well worth your attention. You’ll be surprised at the variety.

If you are lucky enough to spot a coyote, they are looking quite plush now as their coats will have grown thicker in the late fall. It’s fun to watch them hunting in snowy fields, with their ears attuned and head cocked to the sounds of rodents under the snow, ready to pounce and dive headfirst into the snow.

Oregon’s big four ungulates—mule deer, Rocky Mountain elk, pronghorn and Rocky Mountain bighorn sheep—are concentrated in the winter time and, thus, can be easier to find and watch. Look for places where snow cover is thinner and where there is brushy, or treed, cover for the deer and elk. The Malheur National Wildlife Refuge can be a great place to watch mule deer in rut, from late November through December. Just be careful if you do see deer or elk in rut, as they’re not at all tolerant of humans intruding on their romantic interludes. Pronghorn concentrate in lower, thus warmer, areas, and due to their exceptionally keen eyesight and great speed, they’re not as dependent upon cover as the elk and deer. Bighorn sheep will be driven down into lower areas by high elevation snows, but they winter over in fairly hidden and inaccessible canyons, so you’re not likely to see them. However, exploring the rugged east side canyons on Steens Mountain, or on Hart Mountain where ODFW has introduced some bighorns, may yield sightings.