Chinese cork oak is a hardy species of oak from Japan, China and Korea. The corky bark, straight growth habit as well as its glossy leaves makes it a an outstanding ornamental oak. The cork of the bark is harvested for use to a limited extent but the yields are smaller than the cork oak, Quercus suber. It also happens to be the host plant for 'the mushroom of immortality' Gandoderma lucidum which is grown in China.
The acorn yields are very good. It is annually productive. The acorns are small and are deeply seated into a furry cap. Chinese cork has done well at my farm in southwestern Michigan is considered one zone hardier than sawtooth oak. It has a straight growth habit and is easy to limb up making a symmetrical tree. Acorns are produced from seed in roughly 8-12 years from seed. In the red oak group, it takes two years to produce an acorn after pollination. The acorns can be found in both stages of development on the same branch. They tend to cluster all along the branches in great profusion.
This species has potential in cold and dry climates as well making it a good oak for areas were rainfall fluctuates and summers are typically dry. It produces a long thin taproot that goes very deep into the soil even as young seedlings. It transplants well and is easy to establish in a nursery setting. This species is normally not available in commerce but is found in several arboretums. It has never really been commercially produced unlike the sawtooth oak which is similar in many ways.
|Genus & Species||Quercus variabilis|
|Seed Source||Korea. Japan. Originally wild collected sources.|
|Hardiness||minus 20 F or more. -25F in its current location. No frost cracks.|
|Pollination Requirements||Will need an additional pollinator to produce a good crop of acorns. Two trees is enough to aid cross pollination. But self pollinating to a certain extent as well. One lone tree at my farm produces acorns isolated. So probably true to type.|
|Soil||Does well in loam or even pure sand|
|Climate||Seems to tolerate extreme heat as well as cold. Very versatile. zones 5-9.|
|Ease of Cultivation||One of the best oaks that can establish quickly and develops side branching even as a young tree. A vigorous ornamental tree and has potential for its cork and acorn production. Easy to grow in a wide variety of soils. Similar to sawtooth oak in many ways but hardier.|