Mass mortality of ancient oaks

Not only was the meager forests of Southern California fire season, turning to ashes every year hundreds of acres of land, so now even added a new attack — the enemy hexapod.

By this natural disaster was for the county of San Diego voracious pest size in centimeters, destroying standing oak groves. In English it is called persistent insect: goldspotted oak borer, or abbreviated GSOB, that can probably be translated as zolotopyatnisty oak borer beetle, bark beetle. (In Russia, it has a counterpart — Zlatka oak.) Beetle has puleobraznuyu shape, dark green in color and six golden-yellow spots on the back.

Mighty thickset California oaks are vulnerable to the onslaught of hordes of hexapod. These beetles do not even have natural enemies. They do not eat birds, and nothing prevents them from freely reproduce. Beetles grinders introduced into the bark of the tree, dig it moves, eating wood, females lay eggs in the same place. New generation hatched larvae burrows deeper, using the through-passages, and also feeds on wood, until it became the body of the tree in the dust. Struck oak from green to brown and brown and dies.

Dead trees are bare at the federal, state and private lands, on Indian reservations, in communities and Guate Descanso, in the upmarket seaside area of La Jolla, camping around Burnt Rancheria at the Cleveland National Forest Park, in the hills in the canyon and on the coast. U.S. Forest Service once planted saplings shallow coastal shores, growing oak trees to rest was sheltering from the scorching rays of the sun. Now, from the shady oak trees were only skeletons.

Over the past 10 years in the county has lost more than 80,000 oak trees, and if the march of half-inch pests do not stop, will be in danger of extinction 10 million acres of forest red oaks. Moreover, researchers from the University of Riverside fear that GSOB can spread throughout California and beyond. Volunteer San Diego on their own initiative have developed an early warning system for all of southern and central counties, up to Ventura.

Alas, this is not the first six-legged diversion. In the middle of the last century, was brought to the United States Court of East Asian termites, the worst of their kind — formozanskih that have no equal in the extravagance, the rate of reproduction and adaptability. 20 years — until such time as they are sly habitable new continent, spreading and breeding ground for many millions of colonies — their existence no one even knew. Americans learned about the tiny blind immigrants only when they began to eat the inside of their home. Today termites — the scourge of number one in all the southern and central states.

Then came the so-called "Africanized" killer bees (Apis mellifera scutellata), which differ in size, unusually aggressive and highly toxic venom. Killed by their bites in South America, people in the hundreds, the victims — the thousands. Thousands went to the expense and mortality from their bites of pets and animals. Steadily moving north, the bees have won all of South America, Central and then moved to the North.

Wikipedia even has an animated map of the United States, clearly indicating their progress. Under the card signed: "The spread of Apis mellifera scutellata across the U.S. from 1990 to 2003." And about where they go from 2003, nowhere and no one has reported.

Instead, they were replaced in the same year came the giant "killer wasps", 4 cm in length. One such swarm settled even in the building of the U.S. State Department. It was also the invasion of red ants were moving continuous avalanche, up hill and down dale, through the gardens and house. And now here's another invasion — beetles beetles.

These beetles do not attack the weak, old trees, and healthy and young, to admire the majestic splendor of county residents mighty spreading crown. Oak trees are dying on the slopes and in the valleys, on the Pacific coast, on the streets and in private yards. This is a real epidemic, which Californians do not know how to fight.
Of course, against the background of an endless succession of disasters, global reach and taking lives, oak bug may seem picayune problem, not worthy of attention. And yet …

First, the California oak — it's not just a tree, and only decoration. He is also the breadwinner. Its acorns are a major food source for at least 45 different species of wildlife. Second, oak is a symbol of California, her pride. In each city, the state can be seen at least a dozen streets in the title with the word oak. He zealously protected by law.

My son, an architect, says that before embarking on any design, he must find out whether the area of oak trees. If not — this is indicated in the project. If there is, this is a real headache. All calculations are done in view of its presence. No one has the right, without special permission, and without an invitation specialist Executive cut down on the lot, not only the tree, but even a branch on it. Under a tree, in all the projections cast their shadows, are not allowed to build anything, so as not to damage the root system.
And the trees in front of the residents of San Diego County catastrophic die one by one. Mass of death, indicate scientists, means the loss of recreational areas for locals and habitats for wildlife, as well as an increased risk of forest fires, as the dead wood in the forest — the perfect food for the fire.

Among other things, there arises another problem Yeshe. If the tree died in the habitats of people from it because you also need to get rid of, so much so that it does not spread further infection. And this is more than an expensive pleasure. Removal of one of the infected tree, depending on its size, costs from 700 to 10 000 dollars. Has estimated that, in addition to all other damages caused to people, animals and the environment in general, only the cleaning and removal of dead and dying trees in the County of San Diego will cost tens of millions of dollars. In Ohio, experienced similar losses from other types of beetle pests — emerald ash borer, favoring ash, several small towns have gone bankrupt because of the need to pay the costs of this beetle and ruined their trees.

Beetle GSOB, his behavior and the life cycle is relatively little studied, and to cope with it, scientists have to fill this gap. In addition, their goal — to prevent the sale and transportation of contaminated wood as the main source of GSOB. That is not easy to implement, since this sector is one of the least regulated in California. In support of the planned works at University of Riverside has been allocated 635,000 dollars from the half million federal grant.
Oak pest likely was brought to California from Arizona, says Tom Scott, a specialist in natural resources from the University of UC Riverside. And in Arizona, in turn, he came from southern Mexico and northern Guatemala — with firewood. Of unprecedented mass mortalities of Southern California oak trees, scientists warn, could be the biggest event for the flora and fauna of the region since the Pleistocene. (This is an epoch of the Quaternary period ended 12 000 years
back).

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