engleski

Oak Timber Protection from Ambrosia Bark Beetles in FSC Certified Forests and its Integration within Logging Operations

In FSC certified stands, oak timber protection from ambrosia beetles is restricted in insecticide application. Swarming of ambrosia bark beetles in the early months of winter and their continuous occurrence, interrupted only by few weeks of cold weather throughout the logging period, imposes high risk of damages on exposed oak timber. Phenology of ambrosia bark beetles, especially their period of active flight and search for suitable oak timber, generally coincides with the period of logging in Croatian oak stands. Typically this is the period of winter operations when best quality grades are yielded. Earliest species activity starts already in early January, culminating in March, with late species being active until September. Prolonged exposure of round oak timber on forest roads and forest storage areas increases the risk of ambrosia bark beetle infestation. Current grades of oak timber in European CEN/CENELC standard for oak round timber EN 1316-1 in quality grades Q-A, Q-B, Q-C do not allow any beetle holes in hardwood. Only the Q-C quality grade allows beetle holes in sapwood. Considering strict standards for oak round timber, protection is crucial, especially in favorable weather conditions which occur frequently in recent decades. From the economical point of view, ambrosia bark beetles can reduce oak round timber prices to third of its starting value (reaching 150 €/ m3).Recent field tests were conducted in conditions similar to operational logging during summer when at least five different ambrosia bark beetle species where active. Efficiency of Woodnet® was tested via a classical setup of treated (Woodnet® covered) logs versus control group of exposed oak round timber. Initial tests confirmed that commercial products for round timber protection, like BASF® Woodnet® (polymer reusable net with FSC compliant contact insecticide)can provide high rate of protection for exposed oak timber. Specialists and field workers in logging operations and forest protection are both, forced and encouraged, to establish new methods of integrated oak timber protection. Logging and oak round timber protection operations should become a coordinated part of logging in oak stands considering the high commercial value of oak timber.

integrated protection; oak timber; ambrosia beetles; logging operations; FSC; EN-1316-1; polymer nets

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