Their report appears in the current issue of The Pan-Pacific Entomologist and focuses on Agrilus coxalis, a wood-boring beetle so rare it does not even have an accepted common name. Scientists have proposed the Entomological Society of America common names committee call it the goldspotted oak borer.
Land managers and scientists are concerned about further spread of the infestation because oaks are the dominant tree species in the area. Further tree mortality will increase fire danger and decrease wildlife habitat in southern California.
They are also concerned drought and climate change will make more oaks susceptible to an insect that is not native to California. Oak trees have a nearly continuous distribution in the state, reaching from the infestation area north to the Oregon border.
"We don't know how the beetle arrived in San Diego County because there's a broad barrier of desert around the localities where it was previously collected in Arizona, Guatemala, and Mexico," said Steve Seybold, an entomologist with the Forest Service's Pacific Southwest Research Station and one of the study's authors. "We suspect it was either recently brought to California or somehow expanded its range."
There are reports of oak firewood from Mexico frequently being brought into the area in the past 20 years and that could be how it was introduced, Seybold said.
The first California specimen was collected in 2004 in Cuyamaca Rancho State Park in San Diego County. But, aerial surveys of dying trees in the area suggest it might have arrived before 2002.
Last summer, Seybold and Forest Service Entomologist Tom Coleman assessed oak tree mortality in the Cleveland National Forest near Barrett Lake, Mount Laguna, and the community of Descanso.
It was there they found evidence of beetle attacks in 67 percent of coast live oak, canyon live oak, and California black oak trees. They estimate the infestation has impacted 17,000 trees on the national forest's Descanso Ranger District.
According to the scientists, to prevent further spread more research is needed to determine the beetle's California distribution, seasonal active periods, host preferences, and natural enemies in its native Arizona and Mexico habitat. Further research will also demonstrate how it survives and spreads through oak firewood.
The study, "Previously Unrecorded Damage to Oak, Quercus spp., in Southern California by the Goldspotted Oak Borer, Agrilus coxalis," appears in the latest issue of The Pan-Pacific Entomologist.
Contact: Steven Seybold, PSW Research Station entomologist, 530/219-8717
Sherri Richardson Dodge | EurekAlert!
The personality factor: How to foster the sharing of research data
06.09.2017 | ZBW – Leibniz-Informationszentrum Wirtschaft
Europe’s Demographic Future. Where the Regions Are Heading after a Decade of Crises
10.08.2017 | Berlin-Institut für Bevölkerung und Entwicklung
Controlling electronic current is essential to modern electronics, as data and signals are transferred by streams of electrons which are controlled at high speed. Demands on transmission speeds are also increasing as technology develops. Scientists from the Chair of Laser Physics and the Chair of Applied Physics at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have succeeded in switching on a current with a desired direction in graphene using a single laser pulse within a femtosecond ¬¬ – a femtosecond corresponds to the millionth part of a billionth of a second. This is more than a thousand times faster compared to the most efficient transistors today.
Graphene is up to the job
At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.
Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
26.09.2017 | Life Sciences
26.09.2017 | Physics and Astronomy
26.09.2017 | Information Technology