Just as the buds begin to break, absorbing the clean, refreshing air and showing off their vibrant colors, you take a moment to visualize the green season ahead.
But a slight buzzing sound whirring by suddenly reminds you about all the creepy crawlies that are waking from their winter slumbers, milling about your landscape and trying to enjoy springtime, too.
Springtime pests have nearly received their cue to emerge from the cold, wet earth and begin the growing season's feeding frenzy on your trees and shrubs. Not all pests, however, are apparent by the naked eye. You may have to examine your plants more closely to discover the culprits that have been quietly eating away at their leafy prey.
In recent spring and winter seasons, the Pacific Northwest has escaped the drought that has afflicted the western region of the U.S. for years. Although its summers have suffered some drought, the Pacific Northwest has a much larger issue to address: An increase of borers in trees, the most significant problem among forested areas in the region.
Trees standing among the Rocky Mountains, from New Mexico to British Columbia, and the mountain ranges from California to British Columbia, have suffered the most borer damage in recent years. If you combined the U.S. and Canadian trees borers have killed in those regions, the area would be about the size of Washington State.
"This has been devastating for native pine forests due to the massive outbreak of mountain pine beetle and other coniferous beetles," explains Davey Institute Technical Advisor Leonard Burkhart. "Lodgepole pine and ponderosa pine trees have been killed by the thousands in the U.S. and Canada."
Mountain pine beetles, for example, target stressed trees during the early stages of an outbreak. They tunnel through deep crevices within tree trunks, leaving bark dust, larvae, pupae and galleries behind. Months after successful attacks, yellowish to reddish foliage appears throughout the affected trees' canopies.
When borers weaken or kill trees, the forest fuel load increases and contributes to the risk of forest fires during drought. "If severe, fire danger levels can disrupt work in areas abutting the forest," Burkhart explains. "This has impacted utility line clearance and occasionally residential and commercial arboricultural work."
Many beetles have coevolved with fungal organisms; for example, the mountain pine beetle is associated with the blue stain fungus, which travels from tree to tree during the beetles' feeding process. Unfortunately, the fungus has migrated from native areas to the urban forest in some areas, killing several conifers along the way, such as Deodar cedar and Scot's pine. "The beetle problem in the forest is mimicked at a lower level in the urban area," Burkhart explains.
On the other hand, some east coast residents have received some recent relief from another deadly pest: the Asian longhorned beetle (ALB).
This month, the New Jersey state Agriculture Secretary announced the complete eradication of ALB from the state. The Union and Middlesex Counties had successfully wiped out the last of the ALB population to threat New Jersey's trees.
ALB made its first New Jersey appearance in 2002, but according to the U.S. Department of Agriculture's Animal and Plant Health Inspection Service, the pest was first discovered in the U.S. six years prior in Brooklyn, N.Y.
Davey has been involved with ALB control in several locations within the past few years. In 2011, Davey conducted visual surveys for the USDA to determine whether ALB had been eradicated from New York County, N.Y. Davey Resource Group has performed preventive treatments on potential ALB host tree species as well.
The return of pests to your landscape this season should remind you to keep a close eye on the health of your trees. Regardless of species, size and location, healthy trees are ultimately more likely to prevent pest threats from wreaking havoc on your property.
Photo: Kenneth R. Law, USDA APHIS PPQ, Bugwood