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Home My WebLink AboutCOW Agenda Item IV 07/08/2008 Mount Prospect ~ Mount Prospect Public Works Department INTEROFFICE MEMORANDUM TO: VILLAGE MANAGER MICHAEL E. JANONIS FROM: FORESTRY/GROUNDS SUPERINTENDENT SUBJECT: EMERALD ASH BORER UPDATE DATE: JULY 1, 2008 At the July 8, 2008 Committee of the Whole Meeting, Forestry/Grounds staff will provide an update on Emerald Ash Borer (EAB). As reported previously, EAB poses an ever- increasing threat to thousands of ash trees in Mount Prospect. The purpose of this memo is two-fold. First, it will provide information about the pest's current known presence in Illinois and recent state/federal control efforts. Second, it will provide an update on the Forestry/Grounds Division's recent efforts and upcoming plans for 2008- 2009. PART ONE: Where's EAB in Illinois and what are state/federal agencies doing now? The first Illinois find was in June 2006, near St. Charles. As of today there have been 27 USDA-confirmed finds announced in Illinois. Counties with known infestations now include Cook, Will, DuPage, Kane and McHenry (see attachment A). All Illinois finds are believed to have been brought in by human activity (transfer of ash logs or branches.) The closest find to Mount Prospect was in the town of Golf, approximately six miles from our eastern border. The Illinois Department of Agriculture recently stated that "Current survey data reveals that we are entering a period of time where EAB is on the verge of rapid spread, especially in areas where it has already been confirmed. This will be a significant management problem for every municipality with large ash inventories." Since our last update to the Village Board in March 2007, there have been some notable changes in the strategies of state and federal agencies combating EAB. Unfortunately some things have remained largely the same, in that much of the burden of fighting EAB will be placed on municipalities. On a positive note, the Illinois Department of Agriculture (IDA) has finally hired additional EAB personnel, they have vastly improved their website and they are actively reaching out to educate the public and tree care professionals. However, due to fiscal concerns they are limited in what they can accomplish. Specifically, we do not believe the state is currently paying for any more removals of infested trees (though there may H:\Forestry\EAB IN MP\COW UPDATE 7-1-08.doc have been an exception in one localized area where eradication seemed possible.) Just before the 2007 flight season the IDA did pay for voluntary removal of selected infested trees in certain areas, but it does not appear that that program will be repeated. It is true that legislation known as the EAB Revolving Loan Fund was proposed in 2007 and became law in June 2008. This legislation allows municipalities to borrow federal funds at a low interest rate to pay for certain EAB control measures. Eligible activities include certain surveying activities, removing and replacing infested trees, and purchasing capital equipment to perform those tasks. Recently the IDA has done an about-face on the timing of infested ash removals. After two years of stating that infested ashes must remain standing until after flight season is over, they are now saying that the trees should be promptly removed as soon as they are found. Also this year the IDA has moved on in their surveying efforts, now focusing more on the areas south and west of their current quarantine. (The quarantine has included Mount Prospect since April 2007.) They are now using large purple detection traps baited with Manuka Oil. These traps can detect the presence of EAB adult beetles and are a less destructive, cheaper method to detect EAB than the previous tree removal/bark stripping approach. A supply of these traps has been made available for Illinois municipalities where the state will not be actively surveying, so we in Mount Prospect have obtained and placed 16 such traps which we will be monitoring this summer. The IDA and USDA-APHIS have also backed way off from earlier statements implying they might require removal of even healthy ashes around confirmed finds. In fact, they have not yet required removal of even infested ashes on private property in Illinois, instead leaving that enforcement decision to individual communities. As far as we can see, the state is doing little to try to restrict the movement of firewood within Illinois. There is a state-quarantined area in northeast Illinois out of which ash materials may not legally be moved unless processed to a deregulated state, but realistically the chances of enforcement seem slim. Legislation was passed in 2007 that required the state to promulgate firewood regulations, but the latest word we've received is IDA is still suggesting that municipalities register and inspect firewood vendors in their own communities. The state regulations will apparently address firewood being imported into Illinois, which is somewhat puzzling since there is already a federal quarantine regulating interstate firewood movement. However the state indicated they may be doing some inspections of firewood imports, so that may be beneficial if it doesn't duplicate federal efforts. Federal agencies have been actively researching control measures, including biological controls, developing resistant species and testing various insecticides. Last year in Michigan after much study there was a trial release of tiny wasps that parasitize EAB; they will be closely tracked to see if they can establish populations in the U.S. Also in Michigan, the first native insect that seems able to effectively prey on EAB, at least under certain conditions, was discovered. Both state and federal agencies have become more open to the use of insecticides in the past year. Neither promotes insecticide use, but they acknowledge that individual property owners who can afford to may choose to treat healthy, high value ashes, with the hope that the trees can be kept alive until effective biological controls are discovered. H:\Forestry\EAB IN MP\COW UPDATE 7-1-08.doc PART TWO: What steps has the Village taken recently, and what is planned? The Public Works Forestry/Grounds Division has continued to remain actively involved in Illinois' EAB efforts, in spite of the fact that EAB has not yet been discovered here. Our activities continue to focus heavily on public education, staff training, early detection efforts and attempting to influence a regional approach to the problem. A detailed list of action steps taken since our last Village Board update can be seen on Attachment B. Our plans for the near future include continuing many of the ongoing activities and adding more. Specifically, for 2008 we are proposing adoption of a Village Ordinance change and the first step of an Ash Reduction strategy. For 2009 we propose to replace the removed ashes and further consider future opportunities for ash utilization. Additionally, we are currently seeking Village Board input on whether we should consider selected insecticide treatments as part of our EAB management plan. Details about each of these items follow. Proposed Ordinance Chanqe As a matter of public safety, the Village is responsible for the prompt removal of any public trees which die. In addition, our current ordinances allow us to require the removal of dead or diseased elm trees on private property within ten days of notification. If the tree is not removed, we can force its removal and place a lien on the property to recover the costs. Though extremely time-consuming because of all the follow up and hand-holding required, this enforcement is necessary in order to reduce the spread of disease to remaining healthy elms in our community. Enforcement of this ordinance is one of the reasons that, in spite of heavy disease pressure, we have been able to retain a healthy elm population for about fifty years after the arrival of Dutch Elm Disease. Much like DED, EAB will affect many private property ash trees as well as parkway trees. After a great deal of consideration, we are now proposing to add EAB to the current ordinance. This would give the Village the authority to require removal of infested private property ashes, within the same ten-day time frame, at the property owner's expense. It should be noted that there are a couple drawbacks to this plan. First, unlike DED, EAB has proven to be very difficult to detect in its early stages. Where EAB infestations have been found, it has usually been determined that the insects have been present for a number of years. Because we would not want to sample private ash trees, which is currently done by removing bark, even with this ordinance in place infested ash trees may go undetected for quite some time. Additionally, as with our current program for private diseased elm trees, enforcement will be extremely time consuming. If hundreds or thousands of trees become infested at once, enforcement will likely be unmanageable. Still, all things considered, we now believe this step will be necessary if we are to have any hope of protecting the Village's remaining uninfested ashes. We have become aware that some communities plan to allow property owners who can prove their private ash tree has been properly treated with an approved insecticide by a licensed tree care professional will be allowed to delay removal while their tree remains H:\Forestry\EAB IN MP\COW UPDATE 7-1-08.doc alive, even if it has signs of infestation. This approach would likely make the program more palatable to some ash owners, though it could also result in additional insects being allowed to spread to other trees. If the Village Board is in favor of an ordinance change, we will be happy to draft the recommended language for future adoption. Proposed Ash Reduction For communities with a preponderance of ashes (ie. most every community in northeast Illinois), ash reduction of varying degrees is being recommended by state and federal officials as a means of preparing for the arrival of EAB. The idea of reducing the number of ash trees to mitigate the overall effect of EAB can be traced back to lessons learned from Dutch Elm Disease, an introduced pathogen that decimated native elm populations. American elm trees were widely planted because of their adaptability to urban growing conditions, ease of transplant and superior form. Ash trees were recognized as a suitable replacement for many of the same reasons. The lesson learned from Dutch Elm Disease is that having monocultures can lead to future problems when a seemingly unthinkable pathogen or insect is introduced. Much like the American elm, native ash trees have no resistance to an exotic pest such as Emerald Ash Borer. The Village of Mount Prospect currently has 24,379 parkway trees, of which 4,251, or 17.5%, are ash trees (see Attachment C). The ash population is comprised of six different species and numerous cultivars. All our ash trees are susceptible to Emerald Ash Borer with the possible exception of European ash and Manchurian ash, which make up less than 1 % of our ash trees. The majority of our ashes, by far, are green ash (12% of all parkway trees), followed by white ash (4% of all parkway trees). It is generally accepted by most arborists that no one tree species should make up more than 10% of a community's tree population, in order to reduce the risk of widespread devastation in the event a pest attacks that particular species. The idea of reducing the number of ash trees by selectively removing poor quality trees throughout the Village really has several benefits. The first would be a mitigation of the devastating effect that EAB would have on our budget and the appearance of our tree- lined streets, should numerous trees become infested with EAB simultaneously. By starting to remove selected ash trees gradually over a number of years, we can possibility avoid the problem of having to remove numerous dead/dangerous trees all at once. The second benefit would be to reduce ash populations to a lower level, which will lessen the impact of species-specific problems in the future. Additionally, as planned removals happened throughout the years, replacement trees could be planted the following season. This would further diversify our urban forest by encouraging an uneven aged tree population, which is more stable and sustainable than a population of trees that are similar in age. In the 2008 budget, $25,000.00 has already been budgeted for ash tree reduction. Initially we propose to target ash trees that are under power lines especially those that have been pruned heavily by Com Ed's contractors. In following years we would prioritize other ashes that are in poor condition such as trees that have had recent storm H:\Forestry\EAB IN MP\COW UPDATE 7-1-08.doc damage or a have had a high incidence of broken limbs. We would notify adjacent property owners of our plans in advance. If objections were received we would defer removal of non-infested trees, as long as they were structurally sound. We are now in the process of preparing specifications for our first Ash Reduction Contract, with a planned bid opening date of August 18, 2008. Our proposed reduction contract will combine both tree and stump removal in one contract. This was done to simplify contract administration and perhaps attract a better price than separate contracts. Work would begin in September after Village Board approval, and would be completed some time in November. Plantinq In the 2008 budget, $15,000 was appropriated for ash replacement plantings. We are recommending that every tree that is removed as part of the ash reduction plan be replaced with a 1 %" diameter tree at no cost to the adjacent resident, as long as current spacing requirements are met. The Forestry/Grounds Division would choose the species from a list of those we currently consider underutilized. As with our current reforestation program, the property owner would always have the opportunity to upgrade to a 2%" cost share tree for $100.00 (in this program they would be able to choose the species from an approved list). There would not be adequate time to accomplish the tree/stump removals and plantings all in the same season. Therefore we would recommend a carryover of funds to the 2009 budget. If planting prices remain similar to this year's, next Spring we should be able to replace every tree that was removed as part of the 2008 ash reduction contract. Wood Utilization In general, urban wood has been an under-utilized resource in the past. With the introduction of EAB, the possible uses of ash wood have been increasingly explored. Following the lead of Michigan foresters, a municipal wood utilization team was formed for northeast Illinois. This group is comprised of members of the Morton Arboretum, IDA, the United States Forest Service, and municipal foresters including Mount Prospect Forestry Assistant Dave Hull. This group has started finding outlets and resources for utilizing the projected large volume of ash wood that will likely become available in northeast Illinois. Although most urban wood in our area has been used in the past for firewood, mulch and occasionally pallets, the goal of the team is to find the highest possible use for recycled ash wood. A few possible additional uses for urban wood include park benches, picnic tables, trailer decking, cabinets, furniture, flooring and side boards for trucks. There are also plans for a power plant in Robbins Illinois, which will be fueled by wood chips likely provided by some of the south suburbs. Some municipalities have worked with local sawmills to make furniture or cabinets for public buildings. In Mount Prospect most wood debris generated by Village crews becomes mulch. We maintain a woodchip pile at Melas Park that residents are able to access at no charge. Additionally, we deliver mulch to our residents upon request. Larger wood debris is taken to a local contractor where it is tub ground. Currently Public Works does not have H:\Forestry\EAB IN MP\COW UPDATE 7 -1-08.doc a storage facility for stockpiling larger wood debris, which could limit our opportunities to a certain extent. Should the Village decide to try to use some of the ash wood for future projects, Dave Hull has already been in contact with a local sawmill that can cut and dry the wood. Once the wood is dry, it would have to be designated for a specific use or stored at our facility. One idea to use some of our ash wood for office furniture or cabinetry for the new Emergency Operation Center. Insecticide Use Especially in the past year there has been a flurry of research and advertisement about various insecticides. No one can truthfully provide any guarantees. However, some of the products recently introduced have now been shown, in Michigan and elsewhere, to be quite effective in decreasing the likelihood of infestation if a tree is treated when it is still healthy. The various products have different pros and cons, as well as a variety of application techniques. Common application methods include soil drenches, basal or trunk injections, and trunk and foliar sprays. Most products need to be reapplied every year. There are a number of factors that need to be weighed before insecticide use is considered at all; many of these are spelled out in the attached U of I Extension document (Attachment D). Though this document does not mention the insecticide called Tree-Age (pronounced triage), that product was just approved in April 2008 for use in Illinois. Tree-Age has caused considerable excitement amongst some researchers, especially because it may only need application every other year. Some communities are now considering treating some of their ash trees preventively. Besides cost, part of the difficulty with this is determining which trees to treat. Tree size is one important factor. It is known that small trees under ten inches in diameter are more likely to be protected by insecticides than larger trees. However, does it make sense to treat a small tree annually for, say, 50-60 years until it dies a natural death rather than remove and replace it with a species that will require less maintenance and will fairly rapidly reach the size of the removed tree? On the other hand, even though larger trees are harder to protect, those are the ones whose loss is more devastating, plus it takes much longer for a replacement to achieve that size, and there are far fewer treatments to be paid for until the tree reaches the end of its natural life span. When parkway trees are involved, there is also the added difficulty of deciding which trees you will attempt to save, opening up staff to charges of favoritism no matter how objectively the treatment guidelines are crafted. In spite of these challenges, last fall in Mount Prospect we did try a small trial insecticide treatment. We hired a contractor to apply an imidacloprid soil drench at the base of 208 healthy parkway ashes, at a total cost of $4200.00. We chose White Ashes because they are in general more tolerant of EAB than Green Ashes, plus they are less susceptible to branch failure and often considered more attractive. We purposely chose trees that were not growing adjacent to residential properties, expressly to avoid the issue of perceived favoritism. Some of the trees were in highly visible locations such as the downtown streetscape. Of course it is too soon to know if the treatment had any H:\Forestry\EAB IN MP\COW UPDATE 7-1-08.doc effect, since EAB has not yet appeared in any of our trees, and it should be repeated this year if we choose to spend the money. Last month we surveyed local tree care companies to obtain cost estimates for the EAB preventive treatments they are currently providing. Depending on the product and application technique, prices ranged from roughly $4.00 to $8.00 per diameter inch. Then we used the diameter distribution of our parkway ash population, as seen on Attachment C, to project the extended costs if we were to try to treat our ashes. Though U of I Extension defined small trees as less than 10" in diameter, we used 12" as the cut-off for ease of calculation using our existing data. The resulting cost estimate to treat our 1682 "Smaller" ashes would be $46,694.00 to $93,388.00 annually. Cost to treat our 2666 "Larger" ashes would be $192,840.00 to $385,680.00 annually. Cost of all treatments would be $239,534.00 to $479,068.00 each year. Even if a product could be applied every other year, these costs would appear to be prohibitive. However, because of the improved efficiency of the newer products we felt it prudent to bring these updated projections before the Board, in case they wish to provide input or direction towards some type of treatment plan for our parkway trees. Additional Personnel In closing this memo, I must state my opinion that the full-blown arrival of Emerald Ash Borer will almost certainly tax our existing personnel beyond what is humanly possible, unless we discontinue existing duties. I doubt that our citizens would willingly accept a reduction in services, as they have become accustomed to a high level of service from our department. Even the preparation activities done thus far have often been completed after hours, and this is only the tip of the iceberg. I recommend that consideration be given to the addition of an additional arborist to our Forestry/Grounds staff, starting in 2009, to help us efficiently and proactively cope with this imminent crisis. I concur: I I ~~ '.../ Sandy Clafk c~ Attachments A. Map 0 f Illinois Finds B. Village Action Steps C. Village Ashes--Genus and diameter distribution D. U of I Insecticidal Guidelines (March 08) H:\Forestry\EAB IN MP\COW UPDATE 7-1-08.doc ~+~ ~ (! '>. 1-_ ' -------- \ i\ _____ " '~r- ( ..', ~---~\.- . \\P~------/-~ ~\ . r.f1 Jj1='=fP~ ) ~ I , . .nr7 D4=i~ 01 \ -,~~~ 01 I o .~1\ ~!~''- I ~ l ~r 0 \ p' jc---' -~'\-c-~iID;> '~'. ' fo 1(:- 18~ r-Jl l__ ~ · /' kl-j_~;r- ~ I ~~ ~ f@ 111~1.f(-~ 11 ~<l<__la.~_ i t o't of( 0 II , it _'3.~-- , . I ~', 00 I > N _ 0 _ Q ..- --- . l-:-I-i.-j ~ ~ II, ~ \'~ ~ o I {-ie. ~ . 0 ic)i..\ ,dj . 1\ ---> ~ i l.> tj' / · ~ L1--M-------.\ w /'''''' Zj; L --- 'I 1i : ;> /, _ _--,- ~ ~---- I \.w ~ -I' i J L --- ,1 \ 5 ~ \ I ---1 '1I!l> · a g 'I ---- "---~~'l ''<t ---Sl~.,_ IVI v___",_ -:- ~, M _ ~_~' _ , --.--,,- '~- 1 Q -- --::==~~\~ I N -T , 0 d I,"" ~ ~ ,_ ~ \ ~ ~ ,) \ ) \ , ~ I I ~ @) I ) 00 I~D~~ ~ r"',,- . 3 , J It. 1.),Ii'. __ I ',,- r .... ~ \~ I ~ . " -..---1 ~ 1_\_ "I ~ I I I ~@ 'l---------.f 1 I ~\\ I ~ ! I ! ~ ~ I ; t__~ 01, I lb' .).:;\ ~ I---T I 1 ! JI ~J ~ e!I (" ~, r----- !. , ' ~ ffi I '! 1 . -, : -iil , ~'I\ 1 >- I ><"C.!1 f-- 15 , " s ~ ~ I ~l I @. ~ iol H I ~, ", ~ ' ~ 11 .. ~-. '."r"'- " "~ r'\ \ I I '" ,~., ~ ~\ Q ,t ' Q I, ~" I ~ 1/. ~ 9iI ..' .~ .... ~. " " .... ,. @ o CJ> <3 ::;) o o g; -",,-eo,. .~~ J '\ -\ =-- t/) e t/) e <II OIl: e :::. Q.O 'iiil:l -a::: 1::_ <II III ~~ o III .~ :: I:: 0 L1J1:: ....0 o ._ :::. .!!! III .~ eQ :::. lXI . ;; ^l ., co Q) ~ Q) .~ co -0 Co ~N co _ :J..-- A>. -::; ~. L.. Q) Q) > -.- c_ -u mQ) <(:t:: UJUJ CJ> '0 C co o o ~ ..-- -- I'- ..... o III co III -c C <+= <( o CI) :::> -c Q) E <+= C o () ~ tl <II .~ e 0.; ... e o lXI .s::: t/) oq: 32 e <II ~ t/) '0 .5 == ~ ~r ~~ Attachment B Villaqe of Mount Prospect Action Steps for Emerald Ash Borer March 2007 throuqh June 2008 . Village Board signed IDA Compliance Agreement (March 2007). . Distributed updated news release/newsletter update (March 2007). . Required all landscapers/tree care companies under contract with Public Works to sign IDA Compliance Agreements. . Forestry/Grounds Superintendent helped organize/present EAB Session at APWA Chapter Conference (May 2007). . Forestry/Grounds Superintendent attended research seminar at Michigan treatment site (August 2007). . In recovery efforts after August 23, 2007 windstorm, assured that all debris was processed and hauled to meet terms of IDA Compliance Agreement. . Continued working with Morton Arboretum on trap tree project (Fall 2007). . Superintendent/Assistant continued participation in "EAB Municipal Team" meetings with state/federallresearch/municipal partners. . Continued inspecting public ashes exhibiting symptoms plus private ashes by request. . Updated/restocked EAB displays at Public Buildings. . Superintendent convinced Illinois Municipal League to host an EAB Session at their annual conference (October 2007). . Treated 208 trees with Imidacloprid in trial project (October 2007). . Discontinued $500.00 Reward offer for first find of EAB in Mt. Prospect (December 2007). . Peeled bark from all ash trees removed Winter 07-08 to look for larvae. H:\Forestry\EAB IN MP\Action Steps 7-1-08.doc . Superintendent/Assistant attended research seminar at Morton Arboretum (March 2008). . Village's Certified Arborists toured infested sites in Wilmette/Evanston (March 2008). . Updated Village website (March-April 2008). . Forestry Assistant attended Utilizer Training to learn about harvesting ash for reuse (March 2008). . Wrote Village newsletter article Spring 2008. . Updated EAB display for Downtown Block Party (Summer 2007), Earth Day (April 2008) and PW Open House (May 2008). . Placed 16 Manuka Oil "Purple Traps" in Village trees to detect EAB adults, if present (June 2008). . MPTV 17 taped "Purple Trap" Segment and aired on daily bulletin board (June- July 2008). . Began preparing specifications for first ash reduction contract, for Fall 2008. H:\Forestry\EAB IN MP\Action Steps 7-1-08.doc Attachment C Top 10 Genera in Mount Prospect Parkways April 2007 o MAPLE _ASH o HONEYLOCUST o LINDEN .ELM o CRABAPPLE iii OAK o HACKBERRY . PEAR I!I SPRUCE Parkway Ash Trees in Mount Prospect Diameter Distribution 800.0 700.0 600.0 # Parkway 500.0 Ash Trees 400.0 (4348) 300.0 200.0 100.0 0.0 1 -3 3-6 6-9 9-12 12-15 15-18 16-21 21-24 24-27 27-30 30-33 33 + Diameter Class (inches) Attach ment 0 EMERALD ASH BORER INSECTICIDAL MANAGEMENT UNIVERSITY OF ILLINOIS EXTENSION Entomology Fact Sheet, NHE-163 Department of Natural Resources & Environmental Sciences Efforts to manage the emerald ash borer on a large scale are primarily being conducted by federal and state agencies. There are many unanswered questions concerning the prevention or control of emerald ash borer, including the uncertainty of the effectiveness of any insecticidal control efforts on emerald ash borer. Current large scale activities being conducted to eradicate emerald ash borer or slow its spread . Nursery stock, lumber, wood product, and firewood quarantines . Infestation surveys . Tree removal . Outreach education . Research on the insect and its management options Factors when considering whether to attempt insecticidal control . The only certain method to control emerald ash borer is to remove the tree. . Healthy trees growing in a location with proper soil, fertility, light, wind exposure, and other environmental factors will survive attack longer than those in poorer health. . Weigh the value of the tree in the landscape against the cost of treatment. . If many trees are being removed in an area, it will probably be less expensive to have it removed than at a later date. . A tree in a regulated area is subject to removal by governmental agencies regardless of whether it has been treated or shows signs of borer infestation. . Cost of the purchase and planting of replacement trees not susceptible to emerald ash borer should be considered. . Only ash trees in the genus Fraxinus are susceptible. Mountain ash and all other trees are not susceptible to this borer. . Be sure that a variety of trees is planted in the neighborhood. This ensures that the loss of one or a few kinds of tree in the future will not be as devastating. Features of insecticidal control efforts . Preventative1y treat ash trees no more than 15 miles from known infestations. . Control is more effective on smaller trees, those with a trunk diameter of less than ten inches. . It is more difficult to keep a tree alive that is already infested with emerald ash borer, whether or not dieback is occurring. . Research is ongoing to determine how long treated trees survive and produce normal growth. . Follow insecticide label directions. Professional insecticidal control options . Imidacloprid (Merit) applied onto or injected into the soil around the tree annually within two feet of the trunk. Do not apply into mulch or other dead organic matter · lmidacloprid (Merit, IMA-jet, Imicide, Pointer) injected into the tree annually. · Apply dinotefuran (Safari) in Pentrabark onto the trunk. . Foliar and bark sprays ofbifenthrin (Onyx), cyfluthrin (Tempo), permethrin (Astro), or carbaryl (Sevin) in both mid May and mid June will control visiting beetles. Homeowner do-it-yourself insecticidal control option . Apply Bayer Advanced Tree and Shrub Insect Control, containing imidacloprid, onto or injected into the soil around the tree annually. · Soil treatments should be made within two feet of the trunk. · Do not apply into mulch or other dead organic matter Factors concerning treatment with imidacloprid · Soil injections take I to 2 months to move throughout the tree. · Trunk injections take about 2 weeks to move throughout the tree. · Applications can be made at any time of the year, but are most effective in the spring. · A higher level of control is achieved once the tree has been treated for at least 2 years. Certified arborists provide expertise in properly treating emerald ash borer as well as expertly maintaining the health of ash and other trees and are listed at: http://www.illinoisarborist.org/. More information on emerald ash borer is available at: http://www.IllinoisEAB.com and http:// www.emeraldashborer.info/. If you see emerald ash borer or its damage, contact your local University of Illinois Extension Office listed at: http://web.extension.uiuc.edu/state/ or the Illinois Department of Agriculture at (800)641-3934. Phil Nixon, Extension Entomologist University of Illinois Extension March 2008