Quercus tomentella, the island oak, island live oak, or Channel Island oak, is an oak in the section Protobalanus. It is native to six islands: five of the Channel Islands of California and Guadalupe Island, part of Baja California.

It is placed in Quercus section Protobalanus.

Description

Island oak is a tree growing up to in height.

This species is a relict. Though it is now limited to the islands, it was once widespread in mainland California, as evidenced by the many late Tertiary fossils of the species found there.

Ecology

Island oak hybridizes with canyon live oak (Quercus chrysolepis). Feral goats have been abundant on the island for at least 150 years. The animals have eliminated much of the native vegetation and caused extensive soil erosion. Fenced enclosures have been helpful in the early recovery of some of the local flora.

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File:QuercusTomentellaBerkeley4.jpg|Detail of new leaves.

File:Quercus tomentella kz01.jpg|Leaf detail

File:QuercusTomentellaBerkeley5.jpg|Some new shoots are reddish in color.

File:QuercusTomentellaBerkeley3.jpg|Young tree in Berkeley, CA.

File:QuercusTomentellaBerkeley1.jpg|Some specimens have slightly different leaf shapes.

File:Silva of North America. Volume VIII, Cupulferæ (quercus), The - DPLA - b9f64d18c757dc555a1796e78beca693 (page 159).jpg|Scientific drawing.

File:QuercusTomentellaBerkeley2.jpg|This specimen has slightly longer, pointier leaves.

File:E20160907-0003—Quercus tomentella—RPBG (29462321352).jpg|Scan of the leaves.

File:QuercusTomentellaBerkeley6.jpg|The variety of leaf shapes Quercus tomentella can have.

File:QuercusTomentellaBerkeley7.jpg|The back of the leaves.

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References

  • photo of herbarium specimen at Missouri Botanical Garden, collected in Guadalupe Island in 1875