News tagged with oak
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 |
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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 |
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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 |
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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 |
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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 |
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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 |
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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 |
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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 |
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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 |
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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 |
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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 |
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Calif. utility stumbles on 1.4M years old fossils
(AP) -- A utility company preparing to build a new substation in an arid canyon southeast of Los Angeles has stumbled on a trove of animal fossils dating back 1.4 million years that researchers say will fill in blanks in ...
Other Sciences / Archaeology & Fossils
Sep 21, 2010 |
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SEINet offers desert plant guide online
Imagine that you're going to take a hike in the Superstition Mountains. You love plants, and are always curious about the various bushes, trees and flowers that you encounter in the desert.
Sep 10, 2010 |
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Radioactive boars on the rise in Germany
(AP) -- It was a big shot. A big hog. And a big disappointment.
Aug 20, 2010 |
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Geologist investigates canyon carved in just three days in Texas flood
In the summer of 2002, a week of heavy rains in Central Texas caused Canyon Lake -- the reservoir of the Canyon Dam -- to flood over its spillway and down the Guadalupe River Valley in a planned diversion ...
Space & Earth / Earth Sciences
Jun 20, 2010 |
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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.
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