News tagged with oak
Do urban 'heat islands' hint at trees of future?
City streets can be mean, but somewhere near Brooklyn, a tree grows far better than its country cousins, due to chronically elevated city heat levels, says a new study. The study, just published in the journal ...
Apr 24, 2012 |
5 / 5 (1) |
1
Study finds that mild winters are detrimental to butterflies
The recent mild winter throughout much of the United States was a cause for celebration for many. However, butterfly aficionados shouldn't be joining in the celebration.
Apr 20, 2012 |
5 / 5 (3) |
7
|
History is key factor in plant disease, study finds
(Phys.org) -- The virulence of plant-borne diseases depends on not just the particular strain of a pathogen, but on where the pathogen has been before landing in its host, according to a new study from researchers ...
Apr 19, 2012 |
5 / 5 (1) |
0
Study shows forest insects and diseases arrive in US via imported plants
The trade in live plants from around the world has become a major industry in the United States, with new imports now valued at more than $500 billion annually. According to a study conducted by researchers ...
Apr 09, 2012 |
not rated yet |
0
New website shares information about deadly tree pathogens
Sudden oak death, Port-Orford-cedar root disease and other deadly tree diseases caused by Phytophthora species (pronounced fy-TOF-ther-uhs) are threatening forest ecosystems worldwide. These microorganisms, which are relate ...
Feb 02, 2012 |
not rated yet |
0
Out of Africa and Into the American Midwest
Grasses bend in the wind, their golden tips tracing arcs across fields that stretch toward the horizon. Sunwashed by a fading evening light, these reedy ballet dancers are central figures in savanna, an ecosystem ...
Jan 09, 2012 |
3 / 5 (2) |
0
Holm oaks will gain ground in Northern forests due to climate change
Holm oaks and other forests in lowland areas of Mediterranean mountains could expand by up to 350% due to global warming. In contrast, those forest formations that are more adapted to cold and humid conditions, ...
Nov 08, 2011 |
5 / 5 (1) |
0
Firewood movement leading cause of oak infestation in San Diego County
A catastrophic infestation of the goldspotted oak borer, which has killed more than 80,000 oak trees in San Diego County in the last decade, might be contained by controlling the movement of oak firewood from that region, ...
Sep 02, 2011 |
5 / 5 (1) |
0
Oak trees have a lot of gall
Those valley oak trees (Quercus lobata) in California's Central Valley have a lot of gall.
Mar 31, 2011 |
not rated yet |
0
Pollen also appears outside flowering season
"There is of course a very close relationship between the moment at which pollen is released by plants and the data gathered by the traps used to measure these grains, but this is not always the case", Rafael Tormo, a botanist ...
Mar 18, 2011 |
5 / 5 (1) |
0
Old-growth tree stumps tell the story of fire in the upper Midwest
Researchers have constructed a 226-year history of fire in southern Illinois by looking at fire scars in tree stumps. Their study, the most in-depth fire history reported for the upper Midwest, reveals that ...
Mar 14, 2011 |
5 / 5 (2) |
0
|
New app to report sudden oak death on smartphones
California’s majestic oak trees have been felled by the hundreds of thousands by a disease first reported in 1995 and dubbed “sudden oak death.” To get a broader perspective on the disease, UC Berkeley scientists ...
Jan 06, 2011 |
not rated yet |
0
Comprehensive report on sudden oak death
Synthesizing more than 10 years of cooperative research on the exotic invasive, quarantine sudden oak death pathogen, the USDA Forest Service's Pacific Southwest Research Station (PSW) recently published "Sudden Oak Death ...
Dec 27, 2010 |
5 / 5 (1) |
0
Ravenous foreign pests threaten national treasures
Foreign pests are eating their way through our national forests, destroying majestic scenery and costing taxpayers millions of dollars.
Dec 06, 2010 |
not rated yet |
0
Citizens pitch in to help scientists track spead of sudden oak death
A map plotting the path of destruction that the tree-strangling pathogen known as sudden oak death is taking through the Bay Area shows new infestations in and around neighborhoods throughout the region.
Oct 05, 2010 |
not rated yet |
0
Oak
An oak is a tree or shrub in the genus Quercus ( /ˈkwɜrkəs/; Latin "oak tree"), of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus. The genus is native to the northern hemisphere, and includes deciduous and evergreen species extending from cold latitudes to tropical Asia and the Americas.
Oaks have spirally arranged leaves, with a lobed margin in many species; some have serrated leaves or entire leaves with a smooth margin. The flowers are catkins, produced in spring. The fruit is a nut called an acorn, borne in a cup-like structure known as a cupule; each acorn contains one seed (rarely two or three) and takes 6–18 months to mature, depending on species. The live oaks are distinguished for being evergreen, but are not actually a distinct group and instead are dispersed across the genus.
For more information about Oak, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
