Monday, January 19, 2015
 
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Local Extension offers education of Emerald Ash Borer

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[January 19, 2015]  LINCOLN - On Thursday January 15th, the Logan County Extension Office hosted a class on the Emerald Ash Borer, an invasive insect that has now infiltrated Logan County and can cause death to select varieties of ash trees.

The Emerald Ash Borer (EAB) has been slowly making its way into the Midwest from the Eastern United States. In 2014, Logan County was officially added to the EAB quarantine list along with Sangamon and Menard Counties. According to Scott Schirmer with the Illinois Department of Agriculture’s Bureau of Environmental Programs, in the city of Lincoln four EAB traps were set last year, and of the four, three resulted in collecting the undesirable insect.

The meeting Thursday was hosted by the University of Illinois Extension Educator Jennifer Fishburn. Guest speakers included Schirmer, Aaron Schulz; a Certified Arborist with King Tree Specialists, Inc. from Tremont, and Reinee Hildebrandt, a State Urban Forester for the Illinois Department of Natural Resources.

Jennifer Fishburn, Universtiy of Illinois Extension Educator for Logan, Menard and Sangamon Counties

Fishburn began the morning talking about tree identification. She noted that there are several species of tree that have strong similarities to the vulnerable ashes, and there are also ash tree classifications that are not affected by EAB.

Fishburn said that folks should not automatically assume they have it. She said, often, the first step is to figure out for sure if a tree is a vulnerable Ash species. She said, for example, the Mountain Ash tree is not a true Ash tree. Fishburn said the trees that may be affected are the Green Ash, White Ash, Black Ash, and Blue Ash. In this area, most of the true Ash trees will be either Green or White.

She talked about identifying the tree in winter with no foliage as well as in the summer when the trees are leafed out.

In looking at a defoliated tree, look for a compound leaf stem. On a twig from the tree, there will be bud scales. She said the bud scale on the Green Ash will look like capital letter “D” turned on its side. The White Ash bud scale will appear to look more like a grin or smiley face.

When the trees are leafed out, the leaf will be in a cluster of seven with three sets being directly across from one another and a single leaf on the tip.

The bark of the Ash tree will be light and have somewhat of a diamond shape texture.



Fishburn also pointed out the varieties of “look-alike’s” that often confuse homeowners. She said trees such as Shagbark Hickory, Pecan, Mountain Ash, Dogwood, and Chestnut are often mistaken for Ash trees.

Scott Schirmer with the Illinois Department of Agriculture’s Bureau of Environmental Programs

Scott Schirmer was the next speaker of the morning. He said that to date, ash tree deaths in the United States is exceeding 350 million. In Illinois, approximately 290 communities have been identified as having an EAB presence. Currently, the scope of the infestation in the U.S. includes a geographical area eastward from New York State to Iowa and southward from Michigan to Tennessee.

Schrimer explained that the EAB is an Asian insect that has come across the ocean through various exported items. He said that part of the problem is that the Asian countries don’t do as good a job of monitoring the wood products they use for pallets and shipping materials. A number of insect species have entered the United States by that means. He warned that there would certainly be more in the future. He also noted that the Eastern European countries are more careful than Asian countries, and the U.S. sees fewer problems from that part of the world.

Once the insects make their way to the U.S., they search out living trees in which to take up residency. A chain reaction or cycle then begins where that the insects spread across an area via domestic wood products such as firewood.

Schrimer discussed the role of the Illinois Department of Agriculture’s role in monitoring the EAB. He said that the USDA identifies the situation as an EAB Emergency Program. The components of the emergency program include surveying and identifying the presence of the EAB. The agency is responsible for quarantining affected areas and monitoring quarantine compliance. The USDA also provides community education and outreach as well as doing research on the control and eventual eradication of the EAB.

He spoke of identifying a problem through the typical “D” shaped openings going into a tree and noted that these are hard to find. Other symptoms of EAB will more than likely be noticed before the “D”, and also after it is too late to do much to save the tree.

The EAB causes its damage by burrowing under the bark of the Ash tree where it lays its eggs for the next generation. It is the larvae that do the actual damage by eating the layer under the bark that transfers nutrients from the root system to the upper portions of the tree. The larvae travel upward in a snaking pattern that interrupts the nutrient transfer.

Schrimer said that it would take a large infestation of the EAB to cause significant damage. He said 10, 20, or even 30 individual larvae won’t kill a tree, which is why early detection is the most important aspect of saving a tree.

Schrimer pointed out some signs that a tree is in trouble. One significant indicator is Epicormic Growth. In that scenario, the tree will try to save itself by growing branches and leafing out below the EAB damage on the truck. Another significant sign is woodpecker damage. He said woodpeckers will go in search of the larvae that they know is there. The result is, they will completely peck apart the trunk of a tree.

And finally the tree will tell you it is in trouble through reduction of the leaf canopy. Schrimer said the reduction of the canopy will begin at the top and spread downward in most all cases. He offered a slide showing reduction of the canopy by percentages, 0 through 100. He told the group that trees with 10, 20, 30, or even 40 percent reduction can still be saved. When the reduction reaches 50 percent or more, he said the best action would be to fell the tree and replace it.

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He also cautioned that when one is trying to determine whether or not to save or destroy, consideration has to be given not only to the cost of each solution, but also to public safety.

With several members of the Lincoln Street Department on hand, Schrimer said that as the damage spreads, a tree will become brittle. Because of this, branches will break and fall easily, there are perils for workers in trying to trim the dead material from the trees, and catastrophes can happen.

Addressing the city staff, Schrimer said that it is very important for municipalities to have tree inventory records. He showed examples of inventory records. On the records, he identified the tree species, its location, and its condition. He uses a ranking system to help him know what stage of life the tree is in with a class 1.0 being a newly planted young tree to class 5.0 being a mature, but dead tree that needs removed.

It was also suggested that a municipality use a wide variety of tree species with population percentages on any one variety not exceed 10 percent or so.

He noted that EAB is not the first tree killer to come into the United States, and it will not be the last. He said there are other threats right now that will more than likely eventually become an issue in the Midwest. He specifically named the European Gypsy Moth and Asian Gypsy Moth that prey on Oak trees and the Gold Spotted Oak Borer, which he said was the "EAB of the Oak."
 

Aaron Schulz, Certified Arborist with King Tree Specialists, Inc.

Aaron Schulz was the third speaker. He discussed means of controlling EAB through the use of pesticides. As a professional who specializes in this area, he talked primarily about professional grade insecticides and how they are applied.

Like Schrimer, he cautioned that there is a point when treatment is not the best answer. Using the same slide Schrimer used, he told the group that he would not treat a tree that has exceeded 40 percent canopy loss.

Also, when considering treatment or removal, cost is going to be a factor he said. The products, Schulz spoke about the most, were Xytect, Safari, and Tree-age. The products are applied either as a drench at the base of the tree, soil drench or an injection into the trunk collar.

To determine the treatment cost; the tree is measured in diameter at 4.5 feet above the soil level. This measurement is then identified as the “DBH.” Pesticide treatment can cost between $6 and $12/one inch DBH depending on the type of treatment.

Removal of a tree includes a number of costs, from cutting and removal to stump removal and depending on the size of the tree can be very costly. Schulz said that for younger trees that have less than 40 percent EAB damage, annual or bi-annual treatments can be administered for a number of years before the cost would exceed the cost of removal.

Reinee Hildebrandt, a State Urban Forester for the Illinois Department of Natural Resources

Reinee Hildebrandt was the final speaker of the day. As a member of the Illinois Department of Natural Resources, she was representing the Tree City USA certification program. She noted that the city of Lincoln is already a Tree City and applauded the city for the investment it makes each year in sustaining its urban forest.

She noted that the city of Lincoln spends $5.41 per capita on its urban forest. She said the figure is well above national figures but below the state average. She too talked about the importance of having a tree inventory and also of having a wide variety of trees in that forest.

She suggested that the city create a volunteer tree board to assist in the inventory and management of the tree population. She also noted that the city's tree ordinance may need to be tweaked a bit. She specifically suggested that the ordinance not name the trees that are allowed or not allowed within city limits.

Currently, the city ordinance has a short list of approved for planting and a list of forbidden trees. Hildebrandt said the city should remove those conditions and replace it with “for a list contact the city forestry department.” She said this would give the forestry department the opportunity to amend the list as needed without having to go through the time and expense of amending the ordinance.

Finally, she talked about grant and other funding opportunities to help support the cost of EAB control. She suggested that there are grants available through the IDNR as well as a private corporation called Treefund.org. She said that the Illinois Financial Authority has low-interest loans available. She also suggested soliciting local groups and clubs such as garden clubs, 4-H and Boy Scouts. She noted that an urban forest project could be a great one for a Scout working toward Eagle status.

During the discussion period, one of the most significant questions came from the Lincoln Street Department and pertained to disposal of the trees once they are cut.

Once cut, it is safe to run the trees through a wood chipper for mulch, and it is also acceptable to burn the trees.

Another question: Once a tree is cut, how long would it take the insects to move out of the tree and into another?

The answer: When the tree is cut with the insect in its larvae stage, it cannot move. Eggs are laid in the fall, so if trees are cut and destroyed in the late fall, there would be no opportunity for the insect to escape to another tree.

[Nila Smith]

The University of Illinois has a vast amount of information, including illustrations, to assist homeowners in identifying EAB in their landscapes. To view the website follow this link:
http://web.extension.illinois.edu/firewood/eab.cfm
 

Past related article

Emerald Ash Borer Found In Logan, Menard, and Sangamon Counties
By John Fulton

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