Common Name: Oak
Scientific Name: Quercus species
Family: Fagaceae (the Beech family)
Common Species:
- Sawtooth/Sawthorn Oak (Quercus acutissima) – medium-sized tree
- Encina or California Live Oak (Quercus agrifolia) – medium-sized evergreen tree
- White Oak (Quercus alba) – large tree
- Boz-Pimal Oak (Quercus aucheri) – large evergreen shrub
- Swamp White Oak (Quercus bicolor) – large tree
- Turkey Oak (Quercus cerris) – large tree
- Kermes Oak (Quercus coccifera) – medium-sized evergreen shrub
- Scarlet Oak (Quercus coccinea) – large tree
- Blue Oak (Quercus douglasii) – medium-sized tree
- Black Oak (Quercus emoryi) – medium-sized tree
- Hungarian Oak (Quercus frainetto) – large tree
- Gambel or Shin Oak (Quercus gambelii) – large shrub
- Glaucous-Leaf Oak or Japanese Blue Oak (Quercus glauca) – medium-sized evergreen tree
- Holly Oak (Quercus ilex) – large evergreen tree
- Holm Oak (Quercus ilex ballota) – large evergreen tree
- Valonia Oak (Quercus ithaburensis macrolepis) – medium-sized tree
- Californian Black Oak (Quercus kelloggii) – large tree
- Bull Oak (Quercus lamellose) – very large evergreen tree
- Overcup Oak (Quercus lyrata) – large tree
- Burr Oak (Quercus macrocarpa) – large tree
- Chinkapin Oak or Yellow Chestnut Oak (Quercus meuhlenbergii) – medium-sized tree
- Swamp Chestnut Oak (Quercus michauxii) – large tree
- Mexican Blue Oak (Quercus oblongifolia) – medium-sized evergreen tree
- Pin Oak (Quercus palustris) – large tree
- Dwarf Chinkapin Oak (Quercus prinoides) – large shrub
- Chestnut Oak (Quercus prinus) – large tree
- English or Pedunculate Oak (Quercus robur) – large tree
- Red Oak (Quercus rubra) – large tree
- Post Oak (Quercus stellata) – large tree
- Cork Oak (Quercus suber) – large tree
- Live Oak (Quercus virginiana) – large evergreen tree
- Sierra Live Oak (Quercus wislizeni) – large evergreen tree
- Compton’s Oak (Quercus x hybrid) – large tree
- Schuette’s Oak (Quercus x schuettei) – large tree
Description:
The Oaks are a large family of shrubs and trees, about 600 species, which produce acorns. Oak wood is highly valued for everything from timber buildings and furniture to wine/whiskey barrels and shitake mushroom logs. Acorns can be used for making flour or a coffee/tea substitute. The trees themselves are beautiful, large, and long-lived and work great as windbreaks. If you enough space, oaks are a great addition to a Forest Garden.
History:
Native to the northern hemisphere, oaks are found from tropical to cold climates. Oaks have been used for wood and food for thousands of years. Craftsman around the world have used oak wood for centuries. Because of their long lives and strong wood, oaks have been used as national and political symbols, and because of their use is no many areas of life, oaks have been used as religious symbols as well. In more recent times, a number of hybrids and cultivars have been developed for landscaping purposes. Unfortunately, there has not been much development in producing acorns with less tannin.
Trivia:
- Oak trees can be deciduous or evergreen (a.k.a. “Live Oaks”)
- Oaks produce fruit as a nut called an acorn. The nut contains the seed. The “cap” of the acorn is called a “cupule”.
- The fruit of nut trees, like acorns, are generally referred to a “mast”.
- Most acorns have high amounts of tannin, which eaten in large doses, can be toxic to certain animals, namely horses, cattle, and sheep. Pigs, which in certain locations feed on large amounts of Autumn acorns, can have some issues with the toxins, but this is much less common.
- The primary source of corks for wine bottles and other uses comes from the
- Cork Oak (Quercus suber). Cork is considered a renewable resource, since
- harvesting the cork (bark) is done in a way which does not harm the tree.
USING THIS PLANT
Primary Uses:
- Nut – the “acorn” is typically dried and ground as “meal” or “flour”. Only a few species or improved hybrids have seeds that can be eaten raw (Quercus ilex)
- Oil – only a few species have seeds that can be pressed to expel edible oil (Quercus ilex)
- Young Leaves – cooked. Only a few oaks (Quercus acutissima) have edible leaves.
- Coffee – The seed can be roasted and used as a coffee substitute.
Secondary Uses:
- General insect nectar and pollen plant
- Wildlife food
- Wildlife shelter
- Windbreak
- Most species can be coppiced – every 7-30 years depending on the size wood desired.
- Wood is highly prized for finish carpentry, furniture, tools, barrels, crafts, baskets, as well as posts, fencing, stakes, wedges, roof shingles, firewood, and charcoal.
- Wood and acorn shells can be used for tanning.
- Wood can be used for mushrooms (shiitake!)
Yield: highly variable on species and size of the tree. For example, Q. acutissima can produce up to 125 lbs (56 kg) of acorns per year.
Harvesting: Autumn (October-November). Acorns are harvested after they have fallen from the tree.
Storage: Can be used right away, but can be stored for months if kept dry.
DESIGNING WITH THIS PLANT
USDA Hardiness Zone:
- Sawtooth/Sawthorn Oak (Quercus acutissima) – Zone 5
- Encina or California Live Oak (Quercus agrifolia) – Zone 8
- White Oak (Quercus alba) – Zone 4
- Boz-Pimal Oak (Quercus aucheri) – Zone 8
- Swamp White Oak (Quercus bicolor) – Zone 4
- Turkey Oak (Quercus cerris) – Zone 7-9
- Kermes Oak (Quercus coccifera) – Zone 6
- Scarlet Oak (Quercus coccinea) – Zone 4
- Blue Oak (Quercus douglasii) – Zone 7
- Black Oak (Quercus emoryi) – Zone 7
- Hungarian Oak (Quercus frainetto) – Zone 6
- Gambel or Shin Oak (Quercus gambelii) – Zone 4
- Glaucous-Leaf Oak or Japanese Blue Oak (Quercus glauca) – Zone 7
- Holly Oak (Quercus ilex) – Zone 7
- Holm Oak (Quercus ilex ballota) – Zone 7
- Valonia Oak (Quercus ithaburensis macrolepis) -Zone 7
- Californian Black Oak (Quercus kelloggii) – Zone 7-9
- Bull Oak (Quercus lamellose) – Zone 8
- Overcup Oak (Quercus lyrata) – Zone 5
- Burr Oak (Quercus macrocarpa) – Zone 2-8
- Chinkapin Oak (Quercus meuhlenbergii) – Zone 4
- Swamp Chestnut Oak (Quercus michauxii) – Zone 6
- Mexican Blue Oak (Quercus oblongifolia) – Zone 7
- Pin Oak (Quercus palustris) – Zone 5-8
- Dwarf Chinkapin Oak (Quercus prinoides) – Zone 5
- Chestnut Oak (Quercus prinus) – Zone 5
- English or Pedunculate Oak (Quercus robur) – Zone 4
- Red Oak (Quercus rubra) – Zone 3
- Post Oak (Quercus stellata) – Zone 5
- Cork Oak (Quercus suber) – Zone 7
- Live Oak (Quercus virginiana) – Zone 7
- Sierra Live Oak (Quercus wislizeni) – Zone 8
- Sawtooth/Sawthorn Oak (Quercus acutissima) – Zone 8-3
- Encina or California Live Oak (Quercus agrifolia) – Zone 12-9
- White Oak (Quercus alba) – Zone 8-1
- Swamp White Oak (Quercus bicolor) – Zone 8-1
- Turkey Oak (Quercus cerris) – Zone 8-1
- Scarlet Oak (Quercus coccinea) – 9-4
- Blue Oak (Quercus douglasii) – Zone 9-1
- Glaucous-Leaf Oak or Japanese Blue Oak (Quercus glauca) – Zone 9-4
- Holly Oak (Quercus ilex) – Zone 9-2
- Californian Black Oak (Quercus kelloggii) – Zone 9-5
- Bull Oak (Quercus lamellose) – Zone 8
- Overcup Oak (Quercus lyrata) – Zone 8-4
- Burr Oak (Quercus macrocarpa) – Zone 9-1
- Chinkapin Oak (Quercus meuhlenbergii) – Zone 8-2
- Swamp Chestnut Oak (Quercus michauxii) – Zone 9-3
- Pin Oak (Quercus palustris) – Zone 7-3
- Dwarf Chinkapin Oak (Quercus prinoides) – Zone 8-1
- Chestnut Oak (Quercus prinus) – Zone 8-1
- English or Pedunculate Oak (Quercus robur) – Zone 8-3
- Red Oak (Quercus rubra) – Zone 9-5
- Post Oak (Quercus stellata) – Zone 9-4
- Cork Oak (Quercus suber) – Zone 12-3
- Live Oak (Quercus virginiana) – Zone 11-6
- Sierra Live Oak (Quercus wislizeni) – 10-6
Chill Requirement: likely, but no reliable information can be found
Plant Type: Medium to large-sized Shrubs; medium to large-sized Trees
Leaf Type: Evergreen or Deciduous depending on the species
Forest Garden Use: Canopy Layer, Sub-Canopy (Understory) Layer, Shrub Layer
Cultivars/Varieties: Many species, hybrids, and varieties available.
Pollination: Oaks require cross-pollination. This can come from just about any other species of oak. Pollinated by the wind.
Flowering: late Spring to mid-Summer
Life Span:
Years to Begin Bearing: 5-35 years depending on the species
Years Between Major Cropping: 1-10 years depending on the species.
Years of Useful Life: 200 years is considered young for most species. Oaks can live to 400 years if not cut down. There is an oak over 2,000 years old in California.
PHYSICAL CHARACTERISTICS OF THIS PLANT
Size:
- Sawtooth/Sawthorn Oak (Quercus acutissima) – 16 feet (5 meters) tall and 49 feet (15 meters) wide
- Encina or California Live Oak (Quercus agrifolia) – 49 feet (15 meters) tall and 26 feet (8 meters) wide
- White Oak (Quercus alba) – 65 feet (20 meters) tall and 32 feet (10 meters) wide
- Boz-Pimal Oak (Quercus aucheri) – 16 feet (5 meters) tall and 13 feet (4 meters) wide
- Swamp White Oak (Quercus bicolor) – 82 feet (25 meters) tall
- Turkey Oak (Quercus cerris) – 114 feet tall (35 meters) tall and 82 feet (25 meters) wide
- Kermes Oak (Quercus coccifera) – 13 feet (4 meters) tall and wide
- Scarlet Oak (Quercus coccinea) – 82 feet (25 meters) tall and 49 feet (15 meters) wide
- Blue Oak (Quercus douglasii) – 39 feet (12 meters) tall
- Black Oak (Quercus emoryi) – 39 feet (12 meters) tall
- Hungarian Oak (Quercus frainetto) – 98 feet (30 meters) tall
- Gambel or Shin Oak (Quercus gambelii) – 14 feet (4 meters) tall
- Glaucous-Leaf Oak or Japanese Blue Oak Oak (Quercus glauca) – 49 feet (15meters) tall
- Holly Oak (Quercus ilex) – 82 feet (25 meters) tall and 65 feet (20 meters) wide
- Holm Oak (Quercus ilex ballota) – 82 feet (25 meters) tall and 65 feet (20 meters) wide
- Valonia Oak (Quercus ithaburensis macrolepis) – 49 feet (15 meters) tall and 42 feet (13 meters) wide
- Californian Black Oak (Quercus kelloggii) – 82 feet (25 meters) tall
- Bull Oak (Quercus lamellose) – 115 feet (35 meters) tall
- Overcup Oak (Quercus lyrata) – 98 feet (30 meters) tall
- Burr Oak (Quercus macrocarpa) – 75-100 feet (22-30 meters) tall and wide
- Chinkapin Oak (Quercus meuhlenbergii) – 35-50 feet (10-15 meters) tall and wide
- Swamp Chestnut Oak (Quercus michauxii) – 75-100 feet (22-30 meters) tall and wide
- Mexican Blue Oak (Quercus oblongifolia) – 26 feet (8 meters) tall
- Pin Oak (Quercus palustris) – 82 feet (25 meters) tall
- Dwarf Chinkapin Oak (Quercus prinoides) – 12 feet (3.5 meters) tall and 12-20 (3.5-6 meters) feet wide
- Chestnut Oak (Quercus prinus) – 49 feet (15 meters) tall and 75-100 feet(22-30 meters) wide
- English or Pedunculate Oak (Quercus robur) – 98 feet (30 meters) tall and wide
- Red Oak (Quercus rubra) – 82 feet (25 meters) tall and 59 feet (18 meters) wide
- Post Oak (Quercus stellata) – 65 feet (20 meters) tall and wide
- Cork Oak (Quercus suber) – 65 feet (20 meters) tall and 49 feet (15 meters) wide
- Live Oak (Quercus virginiana) – 65 feet (20 meters) tall and wide
- Sierra Live Oak (Quercus wislizeni) – 65 feet (20 meters) tall and 98 feet (30 meters) wide
Roots: Extremely variable based on the species. Many have taproots, some are heart-shaped root masses, and some are a diffuse, fibrous network.
Growth Rate: Most species grow at a Slow to Medium rate; however, a few species are known to grow fast. Also, many of the hybrids grow at a much faster rate.
GROWING CONDITIONS FOR THIS PLANT
Light: Prefers full sun
Shade: Some species tolerate light shade
Moisture: Medium soil moisture preferred, but the “swamp” species (Q. bicolor, Q. michauxii) can handle pretty wet soils as can Q. robur
pH: most species prefer fairly neutral soil (6.0-7.0), and some species (notably Q. macrocarpa) is tolerant of very acidic to very alkaline soils.
Special Considerations for Growing:
It is likely that all species tolerates juglone (natural growth inhibitor produced by Black Walnut and its relatives). Consider using this tree as a buffer between your walnuts and other plantings.
Propagation:
Easily from seed. Sow immediately in Autumn after the seeds have fallen from the tree.
Maintenance:
Not much maintenance is needed.
Concerns:
Some people can have seasonal allergies to the pollen.
