Magnificent oak tree from the sky islands of the Southwest. The Arizona White Oak is an extremely handsome evergreen oak that is well adapted to our climate here in the Pacific Northwest, handling our coldest winters with ease and not seeming to mind the dry summers, though it does enjoy some deep waterings in mid to late summer. Great wildlife and landscape tree.

Latin Name: Quercus arizonica
Site and Soil: Arizona White Oak requires 1/2 day to full sun and well-drained soil.
Hardiness: Hardy to at least 0F
Bearing Age: 4-5 years after planting
Size at Maturity: 20-60 ft. in height
Pests & Diseases: Oaks are susceptible to Sudden Oak Death, a fungal disease that can kill entire stands of oaks, though we’ve not seen it yet in our area
USDA Zone: 8a, we’re guessing. Plants have been hardy for the past 4 winters here in the PNW

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A stunning evergreen oak from Southern California with leaves that have a wonderful bluish color to them. Englemann Oak is not often planted this far north so these are a bit of an experiment, but the seed was collected by our friend Nick Lake at the highest elevation he could find them so we’re hoping for a decent bit of cold hardiness to these.

Latin Name: Quercus englemannii
Site and Soil: 1/2 day to full sun and well-drained soil.
Hardiness: Hardy to at least 0F
Bearing Age: 4-5 years after planting
Size at Maturity: 20-40 ft. in height
Bloom Time: April
Ripening Time: August
Yield: 50+ lbs.
Pests & Diseases: Oaks are susceptible to Sudden Oak Death, a fungal disease that can kill entire stands of oaks, though we’ve not seen it yet in our area
USDA Zone: 8b, we’re guessing.

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An excellent and varied evergreen oak from Arizona and into Mexico. This widely distributed species takes different forms depending on where it is growing, but all of them are quite beautiful. This batch is from high elevations in Arizona and have proven easily hardy in our Zone 8 climate. Easy to grow in well-draining soil and enjoys an occasional deep watering in dry summer climates but also withstands drought quite well.

Latin Name: Quercus rugosa
Site and Soil: Netleaf Oak requires 1/2 day to full sun and well-drained soil.
Hardiness: Hardy to at least 0F
Bearing Age: 4-5 years after planting
Size at Maturity: 20-40 ft. in height
Bloom Time: April
Ripening Time: August
Yield: 50+ lbs.
Pests & Diseases: Oaks are susceptible to Sudden Oak Death, a fungal disease that can kill entire stands of oaks, though we’ve not seen it yet in our area
USDA Zone: 8a, we’re guessing. Plants have been hardy for the past 4 winters here in the PNW

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A lovely evergreen oak native throughout much of California, the interior live oak can take a small shrubby form in more southern parts of the state or grow into a stately single trunked specimen further north. It has proven itself a reliable street tree here in Portland with exceptional drought tolerance and even handling snow and ice like a champ.

Latin Name: Quercus wislizeni
Site and Soil: 1/2 day to full sun and well-drained soil.
Hardiness: Hardy to at least 0F
Bearing Age: 2-3 years after planting
Size at Maturity: 20-45 ft. in height
Bloom Time: April
Ripening Time: September of the following year
Yield: 50+ lbs.
Pests & Diseases: Oaks are susceptible to Sudden Oak Death, a fungal disease that can kill entire stands of oaks, though we’ve not seen it yet in our area
USDA Zone: 7

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An evergreen oak species from Southern Arizona, the Emory Oak has been prized for millennia for its tasty acorns that have no tannins and can be eaten fresh right off the tree without any leaching. While thought to be marginally cold hardy here, these seedlings are from a particularly high elevation stand northeast of Phoenix, courtesy of the ever tenacious plant explorer Sean Hogan. The acorns are truly delicious from these trees, but it is also a gorgeous ornamental and will make a fantastic evergreen street or garden tree.

Latin Name: Quercus emoryi
Site and Soil: 1/2 day to full sun and well-drained soil.
Hardiness: Hardy to at least 0F
Bearing Age: 4-5 years after planting
Size at Maturity: 20-40 ft. in height
Bloom Time: April
Ripening Time: August
Yield: 50+ lbs.
Pests & Diseases: Oaks are susceptible to Sudden Oak Death, a fungal disease that can kill entire stands of oaks, though we’ve not seen it yet in our area
USDA Zone: 8a, we’re guessing. Plants have been hardy for the past 4 winters here in the PNW

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One of the most widely planted evergreen oaks, the Southern Live Oak is the epitome of a stately tree! With its large spreading crown and enormous branches the Southern Live Oak is instantly recognizable. Native to the Southeastern United States but very easy to grow in nearly all climates where temperatures don’t drop below -10°F, it has proven itself a reliable and drought tolerant street tree here in Portland.

Latin Name: Quercus virginiana
Site and Soil: 1/2 day to full sun and well-drained soil.
Hardiness: Hardy to at least 0F
Bearing Age: 2-3 years after planting
Size at Maturity: 20-35 ft. in height
Bloom Time: April
Ripening Time: August of the following year
Yield: 50+ lbs.
Pests & Diseases: Oaks are susceptible to Sudden Oak Death, a fungal disease that can kill entire stands of oaks, though we’ve not seen it yet in our area
USDA Zone: 7 for sure, probably 6 once established

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One of our absolute favorite evergreen oaks the Silver Leaf Oak Tree lives up to its name with its sage green leaves and gorgeous silvery white undersides that flicker in the wind, glow from the nearest streetlight and thankfully for us terrestrial creatures are best enjoyed from below! The Silver Leaf Oak hails from the always enticing sky islands of Southeast Arizona where it coexists with Arizona Madrone, Emory Oak and Netleaf Oak amongst many other favorites.

Silver Leaf Oak has proven itself easily hardy and very drought tolerant for us here in the Pacific Northwest and has great potential in many other parts of the United States. There’s even one growing in the Denver Botanical Garden! Which is at once amazing yet not all that surprising given that we’ve seen them growing all the way up to 8000’ in their native range, though at that elevation they become very multi-trucked and shrubby. Here in Portland they take on an excellent rounded shape with a straight trunk and grow rather quickly to about 35’ tall. Very drought tolerant but they will grow much faster with a few deep monsoonal summer waterings mimicking their natural precipitation in the Chiricahua’s though well-draining soil is recommended. Acorns are edible but on the smaller side and high in tannins. Given the gorgeous olive-like foliage of this species, its adaptability across a wide range of climates and quick growth rate it’s an outrage that this species isn’t more widely planted. As a street tree, a windbreak, a specimen tree, or wildlife habitat planting, the Silver Leaf Oak has sent its tap root deep into our hearts.

Latin Name: Quercus hypoleucoides
Site and Soil: Silver Leaf Oaks like 1/2 day to full sun and well-drained soil.
Hardiness: Hardy to at least 0F
Bearing Age: 2-3 years after planting
Size at Maturity: 20-35 ft. in height
Bloom Time: April
Ripening Time: August of the following year
Yield: 50+ lbs.
Pests & Diseases: Oaks are susceptible to Sudden Oak Death, a fungal disease that can kill entire stands of oaks, though we’ve not seen it yet in our area or on Silver Oaks
USDA Zone: at least Zone 6, possibly lower

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The iconic oak of the Willamette Valley, the Oregon White Oak was a key part of the oak savannah that dominated the Willamette Valley prior to European invasion. Trees can eventually reach a stately 100 feet or so and their gorgeous spreading form is quite the sight to behold on older specimens. Some trees of great age can still be seen in pockets of the valley. Excellent wildlife tree and a gift to future generations wherever they are planted.

Latin Name: Quercus garryana
Site and Soil: Oaks like 1/2 day to full sun and well-drained soil.
Pollination Requirements: Self-fertile. Will freely hybridize with other Quercus species planted nearby
Hardiness: Oak Tree is hardy to -20º F.
Bearing Age: 4-5 years after planting.
Size at Maturity: 70-100 ft.
Bloom Time: June
Ripening Time: October
Yield: 100+ lbs.
Pests & Diseases: Sudden Oak Death can be an issue for Quercus species in Southwest Oregon and California but so far we have not seen it affecting the cork oak or oaks in the Portland Metro area
USDA Zone: 5

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The famed Cork Oak Tree of the Mediterranean is one of the most iconic species of that region and is the national tree of Portugal. The outer bark from the Cork Oak is harvested every 7 years or so to produce corks for bottling wine and other beverages. A stunning specimen plant in the urban or rural landscape, this broadleaf evergreen is long lived and very climate appropriate for our region, being well adapted to areas with dry summers and wet, mild winters. Acorns from the Cork Oak are quite large and absolutely adored by pigs. An excellent silvopasture tree.

Latin Name: Quercus suber
Site and Soil: Cork Oaks like 1/2 day to full sun and well-drained soil.
Pollination Requirements: Self-fertile. Will freely hybridize with other Quercus species planted nearby
Hardiness: Cork Oak Tree is hardy to 0º F.
Bearing Age: 4-5 years after planting.
Size at Maturity: 70-100 ft.
Bloom Time: June
Ripening Time: October
Yield: 100+ lbs.
Pests & Diseases: Sudden Oak Death can be an issue for Quercus species in Southwest Oregon and California but so far we have not seen it affecting the cork oak or oaks in the Portland Metro area
USDA Zone: 7

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Also called the Sonoran scrub oak, the Turbinella Oak is one of the best of the shrubby oak species that grow throughout the West. The evergreen foliage is an excellent powdery blue that contrasts perfectly with the purple growth tips. Its a very drought tolerant shrub to small multi-branched tree, but can also handle some big monsoons during the growing season.

Latin Name: Quercus turbinella
Site and Soil: 1/2 day to full sun and well-drained soil.
Hardiness: Hardy to at least 0F
Bearing Age: 4-5 years after planting
Size at Maturity: 4-8 ft. in height and width
Bloom Time: April
Ripening Time: August
Yield: 50+ lbs.
Pests & Diseases: Oaks are susceptible to Sudden Oak Death, a fungal disease that can kill entire stands of oaks, though we’ve not seen it yet in our area
USDA Zone: 7a, we’re guessing.

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