Brown Marmorated Stink Bug (Halyomorpha halys)on Tansey, Glen Burnie, Maryland, August 2014. Photo by Diane F. Evartt.
Asian Longhorned Beetle (Anoplophora glabripennis)
Ranging from 0.75 to 1.25 inches in length, the Asian Longhorned Beetle is a very noticable insect. Also known as the Starry Sky Beetle, this insect is primarily black in color, with white patches along the edge of its shell. Its long antennae, which give the beetle its name, are covered with interspersed black and white bands over the entire length. The Asian Longhorned Beetle is sometimes mistaken for a member of the Sawyer (family Monochamus) family of beetles, which is similar in size and pattern.
Upon discovery of any beetle suspected of being the Asian Longhorned, the insect should be captured and reported to the Maryland Department of Agriculture.
Asian Tiger Mosquito (Aedes albopictus)
A tiny creature, the Asian Tiger Mosquito ranges from 0.06 to 0.38 inches in length, and is black in color with white striping along its legs and body. Unlike other species of mosquitos, it is much more prolific in urban areas. This is due in part to its ability to lay and hatch eggs with much less water than domestic species. Whereas most indigenous species are common to wetlands and require larger bodies of standing water, this species can thrive on the standing water found in childrens toys, lawn furniture, or even something as small as a disposable plastic cup. Combined, a lack of natural predators, and its ability to "crowd out" feeding areas, have made it the primary pest insect in many areas of the State.
The total life cycle of the Asian Tiger Mosquito is approximately a year, with eggs being laid regularly during warmer months. Laid just above water level, eggs can remain viable over the Winter even though exposed to the elements. Upon hatching, larvae go through a series of molts, and can mature as early as May. Upon reaching maturity, females may lay eggs weekly depending on environmental factors. Over the course of her life, a female may lay as many as 300 eggs.
Another threat posed by the Asian Tiger Mosquito is its role as a vector for numerous diseses to both people and pets. Among other diseases, it is a known carrier of the West Nile Virus.
Black Vine Weevil (Otiorhynchus sulcatus)
Brown Marmorated Stink Bug (Halyomorpha halys)
Emerald Ash Borer (Agrilus planipennis)
First recorded in Maryland in 2003, the Department of Agriculture issued a quarantine on planting and transporting ash trees within or through Prince George’s County after borers were again discovered in 2006. In 2008, the quarantine was expanded to include Charles County in an effort to restrict the spread of the known infestation along the County line. The Department also is hanging traps in other threatened areas of the State to determine possible borer infestation.
Fire Ant (red imported) (Solenopsis invica)
Gypsy Moth (Lymantria dispar)
Hemlock Woolly Adelgid (Adelges tsugae)
Japanese Beetle (Popillia japonica)
Possessing distinct copper-colored forewings that serve as a shell when not in flight, the Japanese beetle ranges from 0.4 to 0.6 inches in length. Destructive to foliage, this beetle feeds off leaf matter between the veins.
Although Japanese beetle traps are readily available and effective, recent studies show that these traps may draw more beetles than they trap. This, in turn, leads to more foliage destruction along flight paths, as well as at the trap's location, than would have occurred without the trap.
Pine Shoot Beetle (Tomicus pniperda)
Beetle, Oriental (Exomala orientalis)
© Copyright Maryland State Archives
(no recorded cases in Maryland; classified as potential threat)
First discovered in the United States in 1996, the Asian Longhorned Beetle has been found in Illinois, New Jersey, and New York. This species is considered a serious threat due to its voracious appetite for hardwood trees, its high reproductive rate, and the lack of any natural predators.
In Maryland, the Asian Tiger Mosquito was first discovered in Baltimore City in 1987, and has since spread to all Maryland counties except Allegany and Garrett.
The Black Vine Weevil is classified as an Invasive Species of Concern in Maryland. Reproducing asexually, the weevil lays eggs at the base of herbaceous perennials, such as yews, rhododendrons, and hostas. Upon hatching, the larva feed on the trunk of the bush, often feeding until the base is chewed clear through.
First recorded in the United States in 1998, the brown marmorated stink bug established a presence in Maryland by 2009. Nearly identical in appearance to the native stink bug, the brown marmorated stink bug is difficult to differentiate from its local cousin. Distinguishing this invasive species are the white bands on its antennae, which indigenous stink bugs lack. Also, the female brown marmorated stink bug may lay two or more batches of eggs each year, while the native female stink bug produces just one.
(only two recorded Maryland cases, both in Prince George's County)
Although only a limited presence in Maryland at this time, the Emerald Ash Borer poses a great danger to the State’s wildlands. Responsible for the destruction of millions of trees throughout the country, the borer potentially could destroy millions of acres of woodland throughout the State.
(isolated colonies recorded, none established)
Imported from South America in the 1930s, the Imported Red Fire Ant is classified as an Invasive Species of Concern in Maryland. While this species has been found in Maryland, no established colonies have been recorded in the State.
Introduced to the United States from Europe in the 1890s, the Gypsy Moth did not establish a presence in Maryland until the late 1970s and early 1980s. Although great pains are undertaken by federal, State and local agencies to reduce and slow the spread of the species, studies predict that stopping the spread of Gypsy Moths altogether is impossible. Further complicating efforts, an Asian cousin, the Japanese Gypsy Moth (Lymantria japonica), was introduced to the West Coast in 1991. At this time, none of these have been found in Maryland.
Although established from Tennessee to Maine, and found throughout most of the State, as of 2009, no established colonies have been reported in Southern Maryland (Charles & St. Mary's counties) or the lower Eastern Shore (Dorchester, Somerset, Wicomico, & Worcester counties). Known for creating a distinct white "wooly" wax along infected branches, the Adelgid itself is often unnoticed, due to its nearly microscopic size. As an adult, the Adelgid is no bigger than a period on a printed page.
First recorded in United States in 1916, the Japanese Bettle now is found in most states east of the Mississippi River, with scattered infestation along the West Coast.
Native to Europe and Asia, the Pine Shoot Beetle first was discovered in the United States in 1992. By 2005, this beetle had been located in five Maryland counties. In an effort to stop its spread, the Department of Agriculture issued quarantine restrictions on sale and transportation of pine trees in and through Maryland. In June 2010, the beetle was found in four more counties, and a second Quarantine Order was issued, covering some nine counties.
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