Entire State of Wisconsin Quarantined for Emerald Ash Borer (EAB)
Tuesday, March 27, 2018
Posted by: James Calkins, MNLA Regulatory Affairs Manager
Infestations Documented in 48 of Wisconsin’s 72 Counties
The entire state of Wisconsin will soon be under quarantine for emerald ash borer (EAB; Agrilus planipennis). The decision to place the entire state of Wisconsin under quarantine was announced by the Wisconsin Department of Agriculture, Trade, and Consumer Protection (DATCP) on March 21 with an effective date of March 30, 2018. Most recently, EAB had been discovered in the City of Eau Claire in Eau Claire County on November 27, 2017, and Eau Claire County was subsequently added to the list of Wisconsin counties quarantined for EAB in December. The Eau Claire infestation was the seventh new EAB infestation identified outside previously quarantined areas in Wisconsin and Eau Claire County was the seventh county added to the Wisconsin EAB quarantine list since August (Chippewa, Eau Claire, Green Lake, Marathon, Marinette, Waupaca, and Waushara Counties). As has been reported previously, EAB has only been confirmed in one new county in Minnesota during the same period (Martin County in August). Prior to the announcement of the pending statewide quarantine, EAB infestations had been documented in 48 counties and 49 of Wisconsin’s 72 counties (68%), including all of the counties in the southern half of the state and seven counties scattered across the northern part of the state, were under quarantine for EAB. In addition, with the exception of two counties (Iron County located east of Ashland County and bordering Michigan’s Upper Peninsula, and Menominee County in the northeastern quadrant of the state), all of the counties in Wisconsin were either already under quarantine for EAB or adjacent to a quarantined county in the state of Wisconsin or a neighboring state. The formal announcement of the statewide quarantine in Wisconsin is available on the DATCP website at https://datcp.wi.gov/Pages/News_Media/EABStateQuarantine.aspx and https://datcp.wi.gov/Documents/EABStateQuarantine.pdf.
As nursery and landscape professionals are well aware, EAB poses a serious threat to green, white, and black ash trees (Fraxinus pennsylvanica, Fraxinus americana, and Fraxinus nigra, respectively) growing in designed landscapes and native ecosystems and Minnesota Nursery and Landscape Association (MNLA) members located in Wisconsin and Minnesota, and that do business across state lines, will want to be aware of this expansion of the EAB quarantine. Nursery and landscape firms should also continue to educate their customers about the threat of EAB and how to manage and prevent the spread of this devastating insect pest.
Although the presence of EAB in 49 of Wisconsin’s 72 counties is a depressing statistic, it is important to note that, with the exception of areas in the far southeastern corner of the state and a few counties bordering Minnesota in the southwestern part of the state, most of Wisconsin (approximately 80%) remains EAB-free. The same is also true for Minnesota where only 16 of the state’s 87 counties (18%), almost exclusively located in the Twin Cities metropolitan area and several counties in southeastern Minnesota, are currently under full or partial quarantine in an attempt to slow the spread of EAB in the state. The reality is that most of Minnesota and Wisconsin remain EAB-free and preventing the spread of EAB to new areas should remain a top priority.
Although updates to the Wisconsin Department of Agriculture, Trade, and Consumer Protection (DATCP) website following the announcement of the statewide quarantine are expected, a list of confirmed EAB infestations in Wisconsin by county, municipality, and date of confirmation is available on the DATCP website here, and a map showing where EAB has actually been detected in Wisconsin can be found at https://datcpservices.wisconsin.gov/eab/article.jsp?topicid=25. See the link to the Minnesota Department of Agriculture (MDA) website below to view a map of the EAB infestations and quarantined areas in Minnesota.
Avoid moving firewood. It cannot be overemphasized that infested firewood is considered a primary vector of EAB and firewood may not be moved from quarantined areas to non-quarantined areas. Better yet, firewood should not be moved around the state or even within an infested county. In Minnesota, firewood may only be moved outside quarantined areas if it has been heat-treated to state standards and certified by the Minnesota Department of Agriculture under a compliance agreement. With the entire state of Wisconsin under quarantine, firewood can legally be moved freely between counties within the state, but the movement of firewood is still discouraged unless it has been properly treated. Remember that, in addition to EAB, firewood can harbor a variety of damaging insect pests and diseases and movement of firewood can introduce these pests to areas that are not yet infested. The interstate movement of EAB-regulated articles continues to be regulated at the federal level by the USDA Animal and Plant Health Inspection Service (APHIS) and by the individual states. Additional information about moving firewood in Minnesota is available at http://www.mda.state.mn.us/plants/pestmanagement/firewood.aspx and at http://www.mda.state.mn.us/plants/pestmanagement/firewood/firewood-dealers.aspx. The Minnesota Department of Natural Resources also has firewood restrictions (http://www.dnr.state.mn.us/firewood/index.html). Information on moving firewood in Wisconsin is available at https://datcp.wi.gov/Pages/Programs_Services/MovingFirewood.aspx and from the Wisconsin Department of Natural Resources at http://dnr.wi.gov/topic/Invasives/firewood.html.
History of EAB in North America and in Minnesota and Neighboring States
Native to east-central Asia, emerald ash borer (EAB; Agrilus planipennis; Coleoptera: Buprestidae) was first documented in North America in 2002 in southeastern Michigan (Detroit area) and has since spread to 30 states in the Eastern, Midwestern (including Minnesota), and Mountain regions of the United States and the far southern portions of two Canadian provinces (Ontario and Quebec). Capable of attacking healthy trees, hundreds of millions of ash trees (Fraxinus spp.) have already been killed in infested areas and all three species of ash native to the Upper Midwest and Minnesota are susceptible to attack – white ash (Fraxinus americana), black ash (Fraxinus nigra; most common in northern Minnesota and the most numerous species in the state), and green ash (Fraxinus pennsylvanica; also called red ash; the most widely distributed species in the state and the most commonly planted species in designed landscapes). As a result, it is estimated that as many as one billion ash trees could be at risk in Minnesota alone.
In Minnesota, EAB was first documented in Ramsey County in 2009 (May); EAB was also confirmed in Hennepin and Houston Counties the same year and all three counties were subsequently quarantined by the Minnesota Department of Agriculture (MDA). Winona County was added to the list of quarantined counties in 2011. Since then, the destructive, non-native emerald ash borer beetle has continued to spread to new areas and, as of this writing, 16 of Minnesota’s 87 counties (18%) are currently subject to complete or partial quarantines in an attempt to prevent the spread of emerald ash borer in the state. Fifteen (15) counties are covered by complete quarantines including Anoka (2015), Chisago (2015), Dakota (2014), Dodge (2016), Fillmore (2015), Goodhue (2017), Hennepin (2009), Houston (2009), Martin (2017), Olmsted (2014), Ramsey (2009), Scott (2015), Wabasha (2016), Washington (2015), and Winona (2011) Counties. A partial quarantine (established in September 2016 and formalized in March 2017) is also in effect for southeastern St. Louis County.
Originally the quarantine in St. Louis County was limited to Park Point in the City of Duluth (November 2015), but has subsequently been expanded to include the southeastern portion of St. Louis County including the entire City of Duluth in response to additional EAB finds. The remainder of St. Louis County is not currently under quarantine. Superior, WI (Douglas County), is also infested and was quarantined in 2013. Although the infestations in Duluth, MN, and Superior, WI, are in areas where winter temperatures tend to be moderated by Lake Superior, these infestations are close to the larger populations of ash trees in the colder, more forested areas of both states. As a result, depending on the actual winter temperatures experienced, we may soon learn whether these infestations will be able to expand and affect ash trees in the adjacent, colder areas where laboratory studies have suggested EAB populations may not be able to reach tree-killing levels as a result of the winter temperatures typically experienced in these regions. With the exception of the City of Duluth and the recent find in Martin County, the current EAB infestations in Minnesota are limited to the Twin Cities metropolitan area and the southeastern corner of the state.
Fortunately the spread of EAB in Minnesota has been slower than what has been experienced in other infested areas and the new finds in Dodge, Martin, and Wabasha Counties, and the expanded quarantines in Goodhue and St. Louis Counties are the only new areas that have been added to the Minnesota EAB quarantine in 2016 and so far this year (2017). Of course, this may change as this is a time of year when new finds are common as a result of woodpecker activity focused on EAB larvae in infested trees as was recently the case in Eau Claire County, Wisconsin. Although the spread of EAB and the number of trees that have been lost in Minnesota have been atypical compared to the more easterly infestations in other states, it is possible that EAB is beginning to spread more quickly. Beginning with the first EAB finds in Minnesota in 2009, six (6) counties were quarantined during the first six years (2009-2014) of the Minnesota invasion, but, including the most recent find in Martin County in August of this year, quarantines have subsequently been added in ten (10) additional counties since then (2015-August 2017). Whether this trend continues remains to be seen.
Emerald ash borer is also present in Iowa (mainly in eastern and southern counties) and a few counties in east-central Nebraska, but has not yet been found in North or South Dakota. The Minnesota and Nebraska infestations, plus infestations in a small number of counties just across the state borders in eastern Kansas, Oklahoma, and Texas, and an isolated infestation in Boulder County, CO, are currently the western-most infestations in North America. In Canada, the EAB infestation is currently limited to extreme south-central Quebec and southeastern Ontario and an isolated infestation in the Thunder Bay, Ontario, area approximately 45 miles northeast of the Minnesota border. The introduction of EAB in North America, which likely occurred in the early 1990s, was a human-mediated event and, more recently, the long-distance and initially-isolated infestations of EAB in the Minneapolis/St. Paul metropolitan area, the Duluth/Superior area, Thunder Bay (Ontario, Canada), Rhinelander (WI), the Kansas City (MO/KS) metropolitan area, the southwestern Arkansas/northern Louisiana/northeast Texas region, and in Boulder County (CO), were almost certainly human-mediated introductions. Along with other control efforts, all concerned must be constantly diligent and take great care to avoid moving EAB-infested materials, including firewood, to non-infested areas to slow the spread of this devastating insect pest.
Selected Links to Additional EAB Information
If you have questions or comments regarding this EAB quarantine update or the status of EAB in Minnesota and/or Wisconsin, contact Jim Calkins, MNLA Regulatory Affairs Manager, at email@example.com; 952-935-0682.
- General information about the Minnesota Department of Agriculture (MDA) emerald ash borer (EAB) program and links to more specific information about EAB in Minnesota are available on the MDA website at http://www.mda.state.mn.us/plants/pestmanagement/eab.aspx.
- The text of the Minnesota EAB quarantine (Version 11; May 9, 2017) is available at http://www.mda.state.mn.us/plants/pestmanagement/eab/eabquarantine.aspx. The quarantine addresses the use and movement of regulated materials which include the insect itself (all life stages); all plants and plant parts of the genus Fraxinus, including nursery stock, scion and bud wood, logs, branches, stumps, and roots, chips and mulch (composted or not); firewood of any non-coniferous species, and other materials deemed to be a risk for the spread of EAB by the Minnesota Commissioner of Agriculture.
- A new, interactive, searchable, ArcGIS online map of specific EAB finds and generally infested, quarantined, and biocontrol areas in Minnesota is available at https://mnag.maps.arcgis.com/apps/webappviewer/index.html?id=63ebb977e2924d27b9ef0787ecedf6e9.A summary of the status of EAB in Minnesota, along with information about some of the activities being pursued by the MDA to better understand and track EAB in the state, are available at http://www.mda.state.mn.us/plants/pestmanagement/invasivesunit/~/media/Files/plants/invasives/statusrpt-eab.pdf.
- Additional information about EAB in Wisconsin is available at http://datcpservices.wisconsin.gov/eab/article.jsp?topicid=20 (once again, updates to this information are expected in response to the new, statewide quarantine).
- And finally, additional information regarding the status of EAB in North America is available on the Emerald Ash Borer Information Network website at http://emeraldashborer.info and from the United States Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) at https://www.aphis.usda.gov/aphis/ourfocus/planthealth/plant-pest-and-disease-programs/pests-and-diseases/emerald-ash-borer.