This latest cold snap could kill some emerald ash borer populations in northern states like Minnesota. But in warmer states like Indiana, the invasive borer is one resilient bug.
“These guys are pretty good at burrowing in underneath the bark of the tree and that tree helps to insulate them from the bulk of the bad weather,” says Megan Abraham, director of the Indiana Department of Natural Resources Division of Entomology and Plant Pathology.
As a result, Abraham says it takes a long cold spell with really cold temperatures to kill off an emerald ash borer beetle. According to Purdue University, it would have to get down to about minus 28 degrees.
Kerry Bridges is an arborist with Tree Guy Incorporated in Bloomington. He says the emerald ash borer is not only used to Indiana winters, but it’s survived in much colder areas like Canada.
An adult emerald ash borer feeds off a leaf. (Purdue University Department of Entomology photo/John Obermeyer)
“I don’t foresee significant change or restriction of that bug’s reproduction and spread,” Bridges says.
What’s more, emerald ash borer and some other insects have a unique way of keeping warm.
Purdue entomologist Cliff Sadof says the reason your nose starts to run when it’s cold out is because your body is trying to keep it from freezing. Mixing mucus with water lowers the freezing point. Sadof says insects like the emerald ash borer do something similar.
“But they are changing the composition of the fluids inside their body, so they act like antifreezes,” he says.
According to the Indiana Department of Natural Resources, the emerald ash borer has devastated ash trees in every county in the state. Bridges encourages homeowners that are having problems with emerald ash borer to keep treating their trees…
The Emerald Ash Borer University is a collaborative effort of Michigan State University, Purdue University, the Ohio State University, Michigan University and Ohio University to provide comprehensive, accurate and timely information on the emerald ash borer to it’s viewers. As of September 21st, it has launched it’s Fall 2017 Webinar in order for the public to become more informed on Emerald Ash Borers. The schedule is as follows:
Imidacloprid, the active ingredient works by killing adults when they feed in the summer before they lay eggs. It slowly kills the two youngest stages of grubs that feed beneath the bark. The later and larger two stages are not killed. Material applied in the fall does not start killing beetles til spring. It takes twice the dose in the fall to get the same effect as a spring application. Trees with a trunk diameter of >20 inches at 4.5 ft above the ground can’t be controlled with imidacloprid.
So if your trees are starting to die I would suggest you skip the fall application of imidacloprid and switch to a professional injection of emamectin benzoate. See Protecting Ash Trees with Insecticides, Purdue Extension Emerald Ash Borer, for more information.
Cliff Sadof, Coordinator of Extension
Purdue University Department of Entomology
Take a look at the recent Indiana Woodland Steward Newsletter, a resource that’s full of a variety of valuable information to foresters, woodland owners, timber marketing specialists and any woodland enthusiasts. This issue includes topics such as a forest management, what private woodland owners are doing about invasive plants, the threat of callery pears, as well as much more.
Check out this IWS Newsletter to stay current in the world of forestry, and feel free to browse archived articles dating back to 1992 for more information.
Rapid growth in the craft brewing industry has created an opportunity for Hoosier farmers to start growing hops. Hops are the female flowers (also called cones) from the hop plant (Humulus lupulus). This high-value, perennial crop is used to flavor and stabilize beer. Now available in a free download is a new publication with a study focusing on growing hops along the fence lines of newly established forest stands. This publication titled Costs and Returns of Producing Hops in Established Tree Plantations is the first of two publications that analyzes the economic opportunities in forest farming for Indiana forest plantation owners. The economic analysis presented in this article is developed for two hops varieties, ‘Cascade’ and ‘Comet’, based on marketability and presumed adaption to low sunlight, respectively.
As part of a new educational video project, Purdue Extension offers essential tips on how to select veneer trees and logs that demand a premium.
The video features Dan Cassens, a professor of wood products at Purdue University, and Greg Hartog of Danzer Americus in Edinburgh, Ind. They give comprehensive details about preferred tree species as well as characteristics, including defects, that are important to the veneer industry.
The advice should be of particular interest to landowners, log brokers, sawmill operators and forestry consultants in Indiana and throughout the hardwood region. Indiana has had a long history of supplying the industry with quality veneer logs and veneer since the early 1900s, Cassens said.
What comes to mind when you think of Purdue Extension? Agriculture and natural resources? Maybe Indiana 4-H? Right on both counts, but perhaps you don’t know how #PurdueExtension helps build health coalitions statewide. Or how we’re revitalizing economic opportunity in Indiana’s rural regions, helping immigrants acclimate to life in our state, or offering parents programs that build confidence and strengthen families. Learn about all of this and more in the 2016 Purdue Extension Annual Report!
Woodlands provide a multitude of environmental (e.g., carbon sequestration, enhance water quality, wildlife habitat), economic (e.g., timber, wood products manufacturing, tourism), and social (e.g., recreation, aesthetics) benefits to Indiana residents. The sustainability of these benefits is strongly tied to stability of the resource. In Indiana, 75 percent of the 4.65 million acres of forestland is owned by families. Actions they take on their property can impact the benefits woodlands provide all Indiana residents. However, many do not understand available options or sources of assistance.
What Has Been Done
The Department of Forestry and Natural Resources, in partnership with many other organizations, helps produce and mail over 31,000 copies of the Indiana Woodland Steward to woodland owners three times each year. This 16-page, two-color publication includes in-depth articles on forest stewardship and health, invasive species and pests, wildlife habitat management, economics, and more.
Subscribers owned more woods (71.6 ac) for a longer tenure (33 years) than the average woodland owner in Indiana based on data from the National Woodland Owner Survey. As a group, they were also more active managers based on the proportion enrolled in assistance programs and who had a written stewardship plan. Fifty-four percent regularly utilized information from the Woodland Steward. In addition, 51 percent of respondents have implemented at least one practice they read about from The Woodland Steward, potentially impacting an estimated 1.2 million acres of forestland. His use of print media to communicate with woodland owners could be considered expensive, but clearly a large number of woodland owners regularly read and utilize the information making the average investment per landowner much lower.
This video explores the origins of Indiana’s state forest system that developed after pioneer settlers cleared the original forests and left behind a nearly barren landscape.
State forests were established to demonstrate how to use science to grow and sustain healthy forest systems. Beginning with just 2,000 acres at Clark State Forest in 1903, the DNR Division of Forestry has expanded to cover more than 156,000 acres at 15 sites.
In the video, IDNR Forestry professionals discuss how management practices contribute to forest health by mimicking natural disturbances. Those practices promote regeneration of oaks and hickories that are valuable food sources for many forest wildlife species. They explain that although timber harvests have increased in recent years, the selective approach they use removes less than 1 percent of the available trees in any given year.
Recently, questions and concerns have come to the Division of Forestry from forest landowners and Consultant Foresters regarding the sale of black walnut trees now, because of Thousand Cankers Disease (TCD).
First, an update on the status of TCD in Indiana.
The Divisions of Entomology & Plant Pathology and Forestry have conducted TCD surveys since 2011 following the first confirmed detection of TCD in the eastern United States – Knoxville, TN August 2010.
The annual surveys include two visual surveys for symptomatic trees and a trapping survey for the Walnut Twig Beetle (WTB), the confirmed vector of the TCD fungus, Geosmithia morbida.
One visual survey occurs in 10 urban areas/cities each year. The other visual survey is gypsy moth trap tenders reporting walnut trees (healthy or with dieback) near each trap location.
In 2015, the urban areas/cities survey examined 1,431 walnut trees and the trap tenders reported 842 walnut trees. Of these only 26 had dieback and none were confirmed with TCD. Since 2011 over 40 urban areas/cities totaling over 3,700 walnut trees and over 5,200 walnut trees reported by trap tenders have been surveyed and less than 2% reported dieback and none had TCD.
The WTB survey involves setting traps baited with the WTB lure. A detection survey sets traps at high risk sites (sawmills, veneer mills, log consolidation yards, green waste sites and along the Ohio border to Butler County Ohio). A delimit survey is conducted at the sawmill in Franklin County and the walnut plantation at Yellowwood State Forest in Brown County due to the detection of WTB and Geosmithia morbida, respectively, at these locations.
In 2015, 249 traps were placed in the detection and delimit surveys. 2,592 samples were examined from the traps. The only detection of WTB was from traps at the sawmill in Franklin County.
Results of the survey efforts are:
TCD has NOT been detected and confirmed from a black walnut tree in the state of Indiana.
There are NO dead or dying black walnut trees in Indiana from TCD.
There is NO widespread TCD mortality in Indiana and none is expected in the near future
The components of TCD – WTB and Geosmithia morbida – have been detected in Indiana.
WTB has been detected in traps, NOT in standing trees.
Geosmithia morbida has been detected from a weevil, Stenomimus pallidus, which was collected from a study tree in the Yellowwood State Forest plantation.
There are NO TCD infected walnut trees in the Yellowwood State Forest Plantation.
Also, there are NO reports of widespread walnut mortality from TCD in the infested states of Tennessee, Virginia, North Carolina, Maryland, Pennsylvania and Ohio.
Therefore, if you are approached to sell your black walnut trees now because the “Walnut Disease” (TCD) is coming and you should sell before it gets to your woods, the response and recommendation is to contact your consulting forester or district forester for advice, follow your current management plan and do not sell the walnut just because of TCD.
I do not anticipate rapid and widespread mortality of walnut once TCD is confirmed from an Indiana black walnut tree.