Gypsy Moth Suppression Program

Alicia Wallace, Program Coordinator

Bay County Building
515 Center Avenue, Suite 503
Bay City, Michigan 48708-5941
Voice: (989) 895-4195

Highlighted Division Programs Include

Boxwood Blight Found in Michigan


Boxwood Blight has been detected for the first time in Michigan. According to Gina Alessandri, director of MDARD’s Pesticide and Plant Pest Management Division,this fungal disease has caused significant losses to homeowners and the nursery industry in states that already have the disease. In Connecticut, the first year after detection, boxwood losses in field-grown and container nurseries exceeded $3million and Michigan could see a similar effect if it becomes established here.

Boxwood is a broad-leafed evergreen shrub that is used as a border plant in many gardens, and branches are commonly used in Christmas wreathsand decorations because they hold their shiny dark green leaves after being cut. Wreaths displayed outdoors have the greatest risk of causing the spread of Boxwood Blight. If the branches are infected with blight, it can spread to the soil and surrounding plants when exposed to the weather. Proper disposal of the wreaths after the holidays is important. MDARD recommends that anyone who has a wreath containing boxwood plant parts should consider it infected and dispose of it by burning or, even better, double-baggingit and including it with their trash for deposit in a landfill.

Boxwood Blight produces dark brown leaf spots and causes rapid defoliation that sometimes kills young boxwoods. Boxwood blight first appeared in the1990s in the United Kingdom and is now widely distributed in Europe. In the United States, the disease was first found in 2011 in Connecticut, North Carolina, and Virginia and has since spread to more than 24 states. Boxwood Blight affects all species of boxwood; however, some species and cultivars are more susceptible than others. American boxwood and English boxwood are highly susceptible. This disease also affects the related shrub, sweetbox, and Pachysandra, a common ground cover. Boxwood and Pachysandra are commonly used in commercial and residential plantings throughout Michigan.

Contact the Bay County Gypsy Moth Suppression Program for more information or to report suspected Boxwood Blight at or by calling989-895-4195. 

Fall Gypsy Moth Egg Mass Awareness

The brilliantfall colors are upon Bay County covering the landscape with the vibrant reds ofmaples, bright yellows of ash, willow and aspen, and the rich oranges andbrowns of oaks indicating our trees are getting ready to rest for the winter. A rain filled fall has not succeeded indulling these colors, though it does encourage the leaves to fall at a muchfaster rate. With the dropping leavescomes an increase in fall yard work tasks.

This isa great time of year to differentiating between live and dead branches beforethe leaves are gone so dead or damaged branches can be trimmed later in thefall after a hard frost, or in the winter. Pruning trees (especially oaks, elm,and ash) later in the year will help protect them from being infected withdiseases that are carried by insects that are attracted to pruning sites ontrimmed trees. Some examples of these diseases are Oak Wilt and Dutch Elm Diseasewhich are both transmitted by small beetles that feed on the sap of trees whenthey are damaged. If you have healthyash trees, it’s a good idea to contact a local nursery or garden center to findout if there are treatments that can be applied at this time of year to protectash trees from Emerald Ash Borer (EAB) insects.



Whileworking in your yard this time of year be on the lookout for gypsy moth eggmasses which are fuzzy in texture, tan to brown colored patches on the sides oftrees, fences, and houses. Gypsy mothegg masses are usually about the size of a quarter and round to teardropshaped. Gypsy moths are not picky about where they will lay their egg masses,so not only can they be found on trees, but also any items left outdoors duringthe late summer. If you find what you suspect to be egg masses, please leavethem in place and call the Bay County Gypsy Moth Suppression Program at 989-895-4195or send an email to doing so the program can record the proper information from the site and takenote of areas where gypsy moth egg mass numbers are increasing. Thisinformation is used to help determine where treatments are needed to slow thegrowth of the gypsy moth population next spring.


Fall iscertainly an amazing time of year to appreciate the beauty and benefits ourtrees provide to us here in Michigan. It is easy to look out over a vibrantstand of fall colors enveloping our trees as far as the eye can see, but it ismuch harder to spot the underlying issues which put our tree’s health at risk.With this timely appreciation comes our responsibility to understand the issuesour forests face, and to actively aid in the prevention of diseases and overallprotection of our trees. Let fall be not just a time to be in awe of changingcolors, but a time in which we all help with being on the lookout for theissues which could be detrimental to the health and future existence of ourtrees.

Emerald Ash Borer (EAB) Fall Tree Survey and Evaluation

Treatment to protect ash trees from the invasive Emerald Ash Borer (EAB) was completed on June 9, 2018. Of the 3,200 ash included in the treatment project in publically owned areas (such as along streets, in parks, etc.) the Gypsy Moth Suppression Program treated 776 ash trees this spring. During late August and September the Gypsy Moth Suppression Program staff will be out to survey ash trees in Bay County in order to evaluate how much the ash trees have grown, collect data to establish the overall health of the ash trees, and determine which ash trees will be treated for EAB in the spring of 2019. Trees treated for EAB during the summer of 2018 will not be treated again until 2021 since the pesticide used will stay in the trees and protect them for up to three years. If you have any questions about the EAB or the tree treatments, please call the Gypsy Moth Suppression Program at 989-895-4195.

August is 'Tree Check' Month for Asian Longhorned Beetles (ALB) 



The Asian Longhorned Beetle (ALB) is an invasive species of beetle that attacks many types of trees.  While the favorite host trees for the ALB are Maple, Birch, Buckeye, and Willow trees, they can live in many other types of trees that are native to Bay County.  The ALB has not been found in Michigan, however there is an area in southern Ohio (near Columbus and Dayton) that is infested. The large white spotted black adult beetles are active in the summer and are sometimes found in swimming pool filters.

 The females chew oval shaped pits into the tree to lay their eggs. Look for trees (especially Maples) with dying branches. The characteristic round, dime sized exit holes and oval egg laying pits can be seen along large branches or on the trunk of infested trees. If you see a suspect tree or beetle, please take photos, record the location, try to collect suspect beetles in a jar, and report it to the Bay County Gypsy Moth Program staff at or via phone at 989-895-4195.

More information about ALB can be found on the Michigan Department of Agriculture and Rural Development website by clicking HERE

For more information about invasive pests, check out our
"Other Invasive Pest" Webpage

Pruning Oak Trees:

Oaks trees are some of our favorite trees and are also favorites of gypsy moths. Gypsy moth populations across Bay County remain low so they should not cause problems for the oak trees this summer. Unfortunately a deadly fungus disease called oak wilt is now becoming active along with the tiny picnic beetles that carry the disease from one tree to another. They are attracted to wounds on trees so stop pruning your oak tree now until next fall. For more information on oak wilt click HERE

National Invasive Species Awareness Week:  Flowering Rush

The beautiful flower of flowering rush (Butomus umbellatus) may look lovely, but is invasive in Michigan. Flowering rush is an aquatic invasive plant that lives along the edges of lakes, streams and wetlands. It is a perennial plant that grows to a height of 3-5 feet. The pink flower that blooms in June makes it easy to identify at that time. This plant is spreading throughout the Saginaw Bay watershed with the majority of sightings along the Shiawassee and Saginaw Rivers. It is important for invasive species managers and the public to help map the extent of flowering rush through MISIN. Knowing the extent of flowering rush will allow managers and organizations to prepare efficient management plans. For more information please click HERE.

Emerald Ash Borer (EAB) Treatment Program 

As you're enjoying the summer trees in full bloom around Bay County know that the staff of the Gypsy Moth Suppression Program have been working hard to save the public trees throughout our community. To protect our trees and horticulture form non-native invasive species that threaten to upset the natural balance in our area. One such non-native invasive species is the Emerald Ash Borer (EAB) which arrived in Bay County around 2007.

Since the EAB treatment program began five years ago, staff has been able to save and maintain over 3,400 ash trees on public lands. These trees provide not only shade to the areas where they stand but many ecological and economic benefits. They reduce heat in the city saving on summer air conditioning costs; reduce winds in the winter saving on heating costs; produce oxygen, remove carbon dioxide and other pollutants from the air improving our air quality and reduce storm water run-off. 

The Gypsy Moth Suppression Program staff have begun measuring and evaluation ash trees in Bay County to determine which trees are likely to survive an EAB attack in order to determine which trees have the best success rate for treatment.

Look for these signs and symptoms on your ash trees as they may be signs of an EAB Infestation: Thinning of upper canopy of the tree; Water Sprouts on trunk and Branches; Cracks in the bark; S-shaped tunnels under the cracks; Wood pecker damage; D-Shaped holes in the Bark. If you suspect that you have Emerald Ash Borer (EAB) infesting your ash trees, please contact Alicia Wallace, Program Coordination of the Bay County Gypsy Moth Suppression Program at 989-895-4195 or for more information about what you can do. 


 Websites of Interest

  • Check out the United States Department of Agriculture (USDA) Animal and Plan Health Inspection Service website Hungry Pests for more information on various invasive pests and what you can do to prevent their infestation. 

Articles of Interest

October is Firewood Awareness Month! 

October is Firewood Awareness Month, and the departments are joining with The Nature Conservancy and the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service to encourage everyone to buy firewood near where they will burn it to prevent starting a new infestation of an invasive insect or disease. If you love fall fun, leave firewood athome. Moving firewood long distances can spread invasive forest pestshidden In or on the wood. Your firewood choices matter and you can help slowthe spread f these tree-killing pests.  Buy locally at your destination to prevent thespread of invasive species.  Check out the DNR Website for more information on how you can help stop the spread of invasive species through firewood. 

  • The movement of firewood is the number one way that new non-native invasive insects get to new habitats.
  • Gypsy Moth egg masses can survive on the bark of trees or household goods and hatch in new locations.
  • Houses destined for Huricane Katrina releaf were delayed due to investation with Gypsy Moth egg masses.
  • Emerald Ash Borer (EAB) were introduced into the United States through the movement of wood packing material.
  • Emerald Ash Borere (EAB) can live in a cut log for over a year and still expand their population to new areas.
  • Asian Longhorn Beetle larva is often transported inside logs from location to location.
  • Other bark beetles and larva can be transported through the movement of firewood.
  • To find out more about how the EAB and other pests can be moved through your firewood, please watch this VIDEO.

Gypsy Moth Suppression Program

The purpose of the Gypsy Moth Suppression Program is to protect Bay County's highly valued trees from the damaging effects of the gypsy moth caterpillar Gypsy moth populations can build to intolerable levels in a short time. When this build up occurs, the caterpillars will defoliate large trees in a few weeks, invade yards and recreational areas, and become a general nuisance to people living in infested areas.

Services offered by the Gypsy Moth Suppression Program include: Piture: Gypsy Moth Larva

  • Monitoring all wooded and residential areas of Bay County for the presence of gypsy moth life stages.
  • Conduct suppression/control activities in heavily infested areas of the county. This includes determining where out-break level populations occur, contracting with an aerial applicator and conducting treatment projects in highly infested areas, and evaluation of treatment results.
  • Cooperate with the Michigan Department of Agriculture's (MDA) grant program for gypsy moth suppression to ensure maximum reimbursement on treatment and administrative costs. By following MDA guidelines and participating in the grant program, Bay County is able to reduce the cost of the program for Bay County taxpayers.
  • Conduct educational programs for schools, property owners, and local civic groups. The program utilizes Bay County Pinconning Park as a staging area for many of these presentations, which include information on the life cycle of the gypsy moth, how it fits into our local ecology, and methods for controlling the gypsy moth.

Gyspy Moth Suppression Program Links of Interest

Emerald Ash Borer

The Emerald Ash Borer (EAB) is an Asian beetle that moved into the south-east corner of Michigan some time in the early 1990's. It's larvae feed on the cambium or conductive tissue just under the bark of ash trees.

The emerald ash borer(EAB) is a very destructive insect that kill all species of North American ash trees. It is responsible for the death of millions of trees throughout Michigan and it has spread to 13 additional states and 2 Canadian Provinces. First found in the Detroit area of south eastern Michigan in 2002, the EAB were most likely introduced into the USA in wood packing material during the early 1990's. The Bay County Gypsy Moth Suppression Program responded to threat to our local forests by adding the EAB education and monitoring to Gypsy Moth Program Activities.

Beneficial Insects

Many insects and related arthropods perform functions that are directly or indirectly beneficial to humans. They pollinate plants, contribute to the decay of organic matter and the cycling of soil nutrients, and attack other insects and mites that are considered to be pests.

Asian Lady Beetle vs Ladybug
There is no difference. Both are lady bugs but the Asian variety has the habit of moving indoors for the winter in large numbers. This is to make finding a mate easier in the spring.

Lady Bug Larvae Resemble Tiny Alligators

Other Invasive Pests & Plants

Besides the Gypsy Moth and the Emerald Ash Borer (EAB), there are many insects and plants that can invade our yards and woodlands. Please check out our information regarding Other Invasive Pests & Plants.

Tree and Garden Articles/Information

Red Squirrel Injury to Spruce Trees in Winter (MSU Extension 01/21/2013)
Pesky red squirrels will feed on spruce buds when other foods become scarce in the winter.

Common Susprects Involved in Winter Landscape Damage
(MSU Extenstion 01/04/2013)
Identifying these pesky, winter, landscape pests by the location of the damage they cause.

Season Ending Tasks in the Garden
(MSU-Extension 12/07/2012)
Even though the weather is getting colder, there are still many tasks to do in your garden before winter settles into the area. This article can explain what you should be doing now to ensure you have a healthy garden next spring.

Additional Information & Assistance

Bay County Gypsy Moth Suppression Program staff members are available to visit your home or site to check for invasive pests such as gypsy moths, emerald ash borers and other native or non-native invasive pests that may be affecting the health of your trees and shrubs. Please call 989-895-4195 if you have any questions.