| molecular differentiation and diversity among the california red oaks (fagaceae; quercus section lobatae). | a recent epidemic of phytopthora (sudden oak death) in coastal woodlands of california is causing severe mortality in some oak species belonging to the red oak (lobatae) group. to predict the risks of spread of this disease, an understanding of the relationships among california's red oak species and of their population genetic structure is needed. we focus here on relationships among the four species of red oak. whereas morphological distinction of quercus wislizeni and quercus parvula can pose ... | 2003 | 12761621 |
| effects of ozone and sulfur dioxide on phyllosphere fungi from three tree species. | short-term effects of ozone (o(3)) on phyllosphere fungi were studied by examining fungal populations from leaves of giant sequoia (sequoiadendron giganteum (lindl.) buchholz) and california black oak (quercus kelloggii newb.). chronic effects of both o(3) and sulfur dioxide (so(2)) were studied by isolating fungi from leaves of mature valencia orange (citrus sinensis l.) trees. in this chronic-exposure experiment, mature orange trees were fumigated in open-top chambers at the university of cali ... | 1989 | 16347849 |
| long-term effects of fire severity on oak-conifer dynamics in the southern cascades. | we studied vegetation composition and structure in a mixed conifer-oak ecosystem across a range of fire severity 10 years following wildfire. sample plots centered on focal california black oaks (quercus kelloggii) were established to evaluate oak and neighboring tree and shrub recovery across a gradient of fire severity in the southern cascade range, usa. shrub and oak resprouting was strongest around focal oaks where conifer mortality was greatest. linear modeling revealed negative relationshi ... | 2014 | 24640537 |
| sensitivity of leaf size and shape to climate within acer rubrum and quercus kelloggii. | * variation in the size and shape (physiognomy) of leaves has long been correlated to climate, and paleobotanists have used these correlations to reconstruct paleo-climate. most studies focus on site-level means of largely nonoverlapping species sets. the sensitivity of leaf shape to climate within species is poorly known, which limits our general understanding of leaf-climate relationships and the value of intraspecific patterns for paleoclimate reconstructions. * the leaf physiognomy of two sp ... | 2008 | 18507771 |
| gibbsiella greigii sp. nov., a novel species associated with oak decline in the usa. | in 2010, cream-coloured, gram-negative staining, facultatively anaerobic enterobacteria were isolated from a single black oak tree (quercus kelloggii) exhibiting decline symptoms in southern california, usa. these 12 isolates were tentatively identified as gibbsiella quercinecans based on partial gyrb sequencing. closer examination of the strains using multilocus sequence analysis, based on partial sequences of gyrb, rpob, infb and atpd genes, and almost complete 16s rrna gene sequencing suggest ... | 2014 | 25107271 |