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''Quercus parvula'' is an evergreen red oak (Section ''Lobatae'') found on north-facing Santa Cruz Island slopes and in the California Coast Ranges from Santa Barbara County north to Mendocino County. It was taxonomically combined with ''Quercus wislizeni'' until resurrected as a separate species by Kevin Nixon in 1980.〔K. Nixon, "A Systematic Study of ''Quercus parvula'' Greene on Santa Cruz Island and Mainland California," Master's Thesis, 1980.〕 The type locality is Palo Colorado Canyon in Monterey County. Three varieties of ''Q. parvula'' are currently recognized:〔Jepson Flora Project (eds.) 2015 Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html July 17, 2015〕 * ''Q. parvula'' var. ''parvula'',〔Greene, ''Pittonia'' 1:40 (1887)〕 Santa Cruz Island oak〔 - Santa Cruz Island, California * ''Q. parvula'' var. ''shrevei'',〔〔K. Nixon, C.H. Muller, “New Names in California Oaks,” ''Novon'' 4(4):391 (1994)〕 Shreve oak〔 or forest oak〔R. Morgan et al, in Santa Cruz Cnty. Pl. Checklst., 22 (2005)〕 - central and northern coastal California * ''Q. parvula'' var. ''tamalpaisensis'', Tamalpais oak〔S.K. Langer, “A New Oak On Mount Tamalpais,” ''Four Seasons'', 9(3): 21-30 (1993)〕 - Marin County, California ''Q. parvula'' differs morphologically from its close relative ''Q. wislizeni'' in the following ways:〔Keuter, "Key to the California ''Lobatae''," ined (2015)〕 * Leaf blades are larger, > (2)4 cm long rather than < 4(6) cm * Leaf blades are thinner, generally < 0.26 mm near the apex rather than usually > 0.26 mm * Current year twigs are 5-sided rather than ± roundish in cross section * Leaf petioles and current year twigs are glabrous to sparsely hairy rather than moderately to very hairy * Nut tips are blunt rather than more sharply pointed * Abaxial golden glandular uniseriate leaf blade trichomes are missing or sparse rather than moderate to dense * Abaxial multiradiate leaf blade trichomes are missing or sparse on the midvein rather than occasional to common * Secondary leaf blade veins are raised abaxially rather than ± not raised ''Q. parvula'' and ''Q. wislizeni'' never produce newly emerging leaves with a velvety coating of red uniseriate trichomes on the abaxial (upper) surface. This separates them from ''Q. kelloggii'' and both varieties of ''Q. agrifolia'' which produce such leaves. ==Ecology== Mainland ''Q. parvula'' is commonly found with or near ''Sequoia sempervirens'' (coast redwood), and often near ''Quercus agrifolia'' var. ''agrifolia'' (coast live oak) and ''Notholithocarpus densiflorus'' (tanoak). ''Q. parvula'' differs ecologically from ''Q. wislizeni'' in the following ways:〔 * Island or coastal habitat rather than Sierra foothills * Associates with ''Sequoia sempervirens'' rather than ''Pinus sabiniana'' 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Quercus parvula」の詳細全文を読む スポンサード リンク
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