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While many parts of our great country are plagued by insect invasions at various times of the year, Pittsburgh experiences more than its share due to a variety of factors.
For one, its warm summers and mild winters make reproduction and survival a piece of cake all year round (and the cake can be food).
The city’s geography, with its hilly terrain and valleys are natural habitats for a myriad of diverse species.
According to Executive Order EO13112, an invasive species is “an alien (or non-native) species whose introduction does, or is likely to cause economic or environmental harm or harm to human health.”
Increased travel and particularly shipping, have served as inadvertent transports for dangerous insects. The state of Pennsylvania has established a dynamic chart of threat categories for invasion by many species that include the following.
18 Most Invasive Insects In Pittsburgh
The Spotted Lantern Fly
Hands down, the most invasive insect currently in Pittsburgh is the Spotted Lantern Fly.
First spotted in Pennsylvania in 2014, this insect is native to China, India and Vietnam.
It has no natural predators and is considered an emerging menace to more than a hundred plants species across the northeastern United States and to Pittsburgh in particular.
This is because the tree of of heaven, which is the lantern flys’ preferred host, thrives in this city.They also feed on fruit, ornamental, and woody plants.
They decimate trees by feeding on the nutrients in their leaves and stems.
Their threat to the state’s economy is enormous because these endangered trees are integral to the billions of dollars in state coffers gleaned from the grape, timber, fruit tree and plant nursery industries.
Professional help from Pestco is often needed if these insects are spotted in profusion on a property, but all of us must do our part if we spot even a single lantern fly. Smash it and kill it as one single female can lay up to 200 eggs!
The Asian Long-Horned Beetle
This destructive wood-boring pest feeds on maple and other hardwood trees.
It grows inside and feeds on the tissues that carry nutrients throughout the body of the tree and eventually kills it.
Also known as the starry sky or sky beetle and native to the Korean Peninsula, this pest was first discovered in 1996 in Brooklyn, New York.
Although it has not yet been found in Pennsylvania ,this beetle is considered a potential pest that has over the course of the last almost twenty-years found it way to Massachusetts, New York and Ohio.
The Hemlock Woolly Adelgid
This aphid-like insect feeds on hemlock trees by inserting its mouth parts into the twig.
In its native habitat in Asia it is not considered a serious problem because its population is managed by natural predators, but in Pittsburgh it is a threat to North American hemlocks, which are vital to the state’s forest and eco-system.
Accidentally introduced to Virginia via Japan in the 1950s, this pest has since spread throughout Pennsylvania, where it is established in all 67 counties.
The Brown Marmorated Stinkbug
The state of Pennsylvania has funded a stink bug research project at Penn State’s College of Agriculture Sciences.
This was borne out of their concern for the widely established presence of these insects throughout the state.
Although scientists believe they are headed west, they have left trail of crop damage and destruction that has been more or less unchecked because they reproduce in great numbers and have no natural predators.
They were first discovered in Allentown in 1998 and Pittsburgh has been at the heart of this established invasion.
Spongy Moth
Also known as the gypsy moth, this established invasive species was accidentally introduced into Massachusetts in 1869 by a French scientist seeking a disease-resistant caterpillar to increase the production of silk.
It has been a highly destructive pest throughout Pennsylvania since 1932.
This moth has killed millions of oak trees and other hardwoods, devouring leaves and causing an inferior quality habitat.
This moth is said to have caused an estimated $868 million in annual damages throughout the nation. Their population surges occur every five to ten years, and the current outbreak began in 2021.
The Japanese Beetle
This invasive species thrives in the Pittsburgh area, where they have no natural predators and many lawns.
The larvae, which are also known as grubs, feed upon grass roots beneath the soil, causing them to turn brown, wither and die.
They eat the leaves of more than 300 varieties of ornamental and agricultural plants, leaving large irregular holes in their wake.
Native to Japan, in 1916 the Japanese beetle was accidentally introduced to a New Jersey nursery and has since spread throughout 13 states, 3 Canadian provinces and at least 3 European nations.
The Emerald Ash Borer
This destructive beetle is a highly established threat to ash trees in Pittsburgh and throughout the state since it was first spotted in 2007.
Currently, this devastating pest has killed an estimated 68,000 ash trees in the Pittsburgh park system, which is almost 16% of the entire tree canopy. The larvae of the Emerald Ash Borer destroy the vascular tissue of the tree which starves it of vital nutrients and kills it.
The loss of these trees has been immeasurable to Pennsylvania’s wildlife habitat and eco-system.
The European or Giant Hornet
The European or giant hornet was first reported in the United States in 1840 and is is a well established species throughout the Eastern parts of the nation including all of Pennsylvania.
Often mistaken for the giant Asian Hornet, European hornets are most commonly found in forests, parks and suburban areas blanketed with trees or other suitable nesting habitats.
The Walnut Twig Beetle
The walnut twig beetle and the fungus it carries is native to nearly all the counties in Pennsylvania. The Pennsylvania Department of Agriculture (PDA) imposed a quarantine on the movement of walnut wood from affected counties in 2011, but repealed it in 2022.
The beetle’s tunneling creates cankers (a small area of dead tissue, which grows slowly, often over years).
These disrupt the tree’s ability to transport nutrients and water, which can lead to death and many trees are killed within three years of the appearance of the first symptoms.
The Fall Army Worm
This insect predator is an annual visitor to the state of Pennsylvania and its counties.
Considered an emerging species, fall army worm caterpillars can cause significant damage to lawns, defoliation of crops and seedling alfalfa. While lawns usually recover, the crops do not.
Consult the experts at Pestco if an infestation should occur, as these insects spread quickly and need to be stopped as soon as possible with insecticides of certain levels of toxicity that must always be compatible with specific plants.
A single female caterpillar can lay up to 2,000 eggs in her lifetime.
The European Fire Ant
So named for the burning sensation its sting produces, their presence has been noted in North America for more a century, but their spread has deemed them a potential threat to many parts of the country, including Pennsylvania.
It is believed they first arrived in Maine in infested pants, as they are small and often go unnoticed.
When these ants invade an area, native ants are displaced and other insects such as local pollinators, are negatively impacted.
Their large colonies have multiple nests and ant queens can live up to 7 years.
Their nests often blend in with their surroundings, making then difficult to detect until they become so large that they interfere with the daily lives of surrounding humans.
The Elm ZigZag Saw Fly
Native to Japan, eastern China, the Korean Peninsula and eastern Russia, this species was first detected in North America in 2020 in Québec, Canada.
This fly has also been found in many Pennsylvania counties and is considered an emerging danger to elm trees upon which it feeds and defoliates.
As larvae, these flies feed in a zigzag pattern from the edge of the leaf toward the middle, and this characteristic is very easily identified.
Their spread can be problematic as they often attach their pupae (eggs) to almost any object that a human can transport.
Usually, professional help is needed to address an infestation and home owners are urged to contact Pestco as soon as possible.
The Spotted-Wing Drosophila
This invasive vinegar (fruit) fly was first discovered in Pennsylvania in the Lake Erie grape growing region in late fall of 2011. It has since spread throughout most of the state.
Unlike other species of fruit flies, females lay their eggs in fruit that is still ripening rather than rotten fruit. This greatly impacts the findustry because larvae can be present in an otherwise healthy crop.
Blackberries and fall raspberries have been particularly impacted as well as blueberries and strawberries.
sIn addition, some crops, such as grapes, experience secondary damage like an increased incidence of fruit rot, which can be even worse.
Allum Leaf Miner
Native to Poland, this invasive fly species was first detected in Lancaster County, Pennsylvania in 2015.
This emerging pest has also been found in other counties as well as other states including:Maryland; New Jersey; New York and Massachusetts.
It attacks crops such as: onion; garlic; leek; chives and scallions. It hides in leaf tissue or soil in winter and emerges in the spring.
The experts at Pestco apply pesticide during the flight period, which attacks both developing larvae as well as adults.
They always use systemic insecticides with an added surfactant(a chemical compound that reduces surface tension between liquids, gases, or solids) because the leaves on these plants are waxy and the larvae are living inside the leaf tissue.
The Red Lily Leaf Beetle
The red lily leaf beetle is native to Europe and is believed to have been transported to the United States inadvertently via a shipment of lily bulbs.
It first appeared in North America in Montreal in 1945 and in 1992 was discovered in Cambridge, Massachusetts.
Since then, this emerging species has been found throughout New England, New York, Pennsylvania, Michigan, Wisconsin, Iowa and southern Canada. Researchers have developed at least a partial solution to the continuous spread of this invasive pest.
They have released into the environment three species of parasitic wasps, two of which have already served as formidable predators of the red lily leaf beetle throughout New England. There is hope they can do the same for other affected states.
The Sirex Woodwasp
Indigenous to Eurasia and Africa, this invasive pest hitch-hiked to North America via wood-packing material.
It first appeared in New York close to Lake Ontario in 2002; then again in Canada in 2005.They are currently spreading throughout the North eastern and western United States and are considered an emerging menace to the state of Pennsylvania and its many healthy pine trees and other conifers.
This insect feeds on and kills the trees with its fungus and venom.
The professionals at Pestco recommend biological control agents like parasitic wasps as the best way to reduce the continuous spread of these destructive marauders.
Cherry Curculio
Also known as the plum curculio, this emerging pest attacks most tree fruits such as:cherries, apples, peaches, nectarines, and plums throughout the state of Pennsylvania including Pittsburgh.
These weevils lay their eggs under the skin of the fruit, which debases every stage of their life cycle. Their intrusion leaves half moon-shaped scars or bumps on the surface of the fruit.
Ants are their primary predators, but often insecticide when applied by professionals immediately after the first group is sighted, can contain this deleterious insect.
The Box Tree Moth
Indigenous to eastern Asia, this highly destructive moth has already invaded Europe and North America. It has been found in Ontario, Michigan, New York, Ohio and Massachusetts.
Although It has not yet invaded Pennsylvania, in its caterpillar stage, this moth is still considered a potential threat to their boxwoods, which comprise traditional landscaping in Pittsburgh.
In heavy concentrations, these insects have the capacity to fully defoliate topiaries and hedges. Boxwoods are the highest-selling evergreen shrub in the nation.
Approximately 150 varieties of boxwood, which are available to home-owners, are susceptible to this invasive pest.
In Summation
Our experts at Pestco are highly trained to deal with any type of infestation. Call them for help.
Homeowners must be mindful and watch over their crops as they would their children.
While all may see like doom and gloom, vigilance can protect prosperous crops with a great deal of love, dedication and care.