Allegheny River Headwaters Watershed Conservation Plan

Allegheny River Headwaters Conservation Plan
Chapter 4. Biological Resources
through the bark to emerge as adults from July to October. Once they emerge, they fly to new or oneyear-old
pine shoots to begin maturation feeding. The beetles enter the shoot approximately 15
centimeters or less from the tip and move up the shoot hollowing out the center of the shoot for 2.5 to 10
centimeters, causing the infected shoot to droop, turn yellow, and eventually fall off. When shoot feeding
is severe, diameter and height growth are reduced, weakening the tree to the point where the beetles begin
using the tree as a host for laying its eggs (U.S. Department of Agriculture, 2002).
Emerald Ash Borer
Introduced into the U.S. accidentally through wood packaging materials, the emerald ash borer
(EAB) is an invasive beetle from eastern Asia and China. It was first discovered in the U.S. in 2002 and
in Pennsylvania in 2007. Although not identified within the project area, McKean County has been added
to the list of counties that are under a firewood quarantine to reduce the spread of EAB. The EAB has
been positively identified in nearby Cameron County.
This invasive, metallic-green beetle is approximately 13 millimeters long, and impacts the health of
ash trees. Infestations of EAB are fatal within one to three years, with no available cure. From May to
August, the adults emerge from over-wintering sites under the bark to mate. The females lay their eggs in
bark crevices, and within 10 days, larvae hatch. The larvae tunnel under the bark to feed and grow
through the fall. They remain dormant during winter, when they pupate and emerge as adults in the
spring, exiting the tree is a unique D-shaped exit hole.
The most effective management method is to prevent further infestation. Infected counties are placed
in a quarantine, which does not permit the transportation of ash products, such as lumber or firewood.
Since most of the general public cannot identify the species of tree from which wood came, the ban
effectively limits the transport of all firewood. The use of pesticides can be effective in controlling EAB
populations, but once a tree is infested, it will die. Wood peckers and two parasitic insect species are
natural enemies of EAB and can reduce their populations.
European starling
The European starling is a hole-nesting bird species that was introduced to the U.S. in 1890 as part of
a plan to introduce all the birds mentioned in the works of Shakespeare. Native to Europe, the starling
competes with native species for habitat and destroys crops.
The European staling is a shinny black, glossed-purple or green bird that is speckled with white
spots. It is approximately 19–22 centimeters long and weighs 60–90 grams. It prefers urban and suburban
habitats, but is also common in grassy areas, such as agricultural fields, pastures, ball fields, and golf
courses. Occasionally the European starling will inhabit open forest and woodland areas, but rarely
inhabits dense or wet forest habitats.
Sirex woodwasp
The Sirex woodwasp, a native to Europe, Asia, and North Africa, has the potential to cause mortality
to pine trees. The adult is a large, robust insect, approximately one to 1.5 inches long with a spear-shape
plate (cornus) at the tail end. Its body is dark, metallic-blue or black with reddish-yellow legs. It was
introduced into the U.S. in 2004 accidently through wood packaging materials. It was first detected in
McKean County in 2007 and Potter County in 2008.
From July to September, the adults emerge from the host tree, and after initial flight, the females are
attracted to stressed pine species. They drill their ovipositors into the outer sapwood and inject a
symbiotic fungus, toxic mucus, and eggs. The mucus and fungus work together to kill the tree, creating a
viable habitat for the eggs. Females lay anywhere from 25–350 eggs. The fertilized eggs become females,
while the unfertilized eggs become males. The larvae feed on the fungus as they tunnel through the wood
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