Emerald Ash Borer in St. Louis A Strategy for Treatment, Removals, and Replanting

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1 Emerald Ash Brer in St. Luis A Strategy fr Treatment, Remvals, and Replanting Frestry Divisin - City f St. Luis June 12, 2016 Infrmatin available at: Intrductin: St. Luis has a rich histry as a natinally recgnized cmmunity frest, but faces the lss f a large prtin f its public and private tree resurce in the years ahead. An invasive and extic pest knwn as Emerald Ash Brer (EAB) has infested ash trees in St. Luis. The pest was discvered by a utility cntract crew wrking fr Ameren in the area near Calvary Cemetery n May 6, EAB is a very serius pest and has a track recrd f killing all untreated ash trees in infested cities since it was initially discvered in the US in 2002 near Detrit, Emerald Ash Brer (EAB) in Missuri Michigan and has spread t several thusand cmmunities in the US. Infestatins have killed tens f millins f ash trees thrughut the eastern United States. It was first discvered in Missuri in 2008 and is currently knwn t exist in the Kansas City area, and parts f sutheast Missuri, St. Charles Cunty and the City f St. Luis. St. Luis Frestry Divisin Preparedness - Since the arrival f EAB in Missuri, the City f St. Luis Frestry Divisin has been practive by updating its current inventry f trees and practively remving sme f the ash trees that are in pr cnditin frm ther causes. Street trees and mst park trees are nw mapped and listed in a cmputerized GIS database. Frestry Divisin develped a preparedness plan using this data and calculated the benefits that ash trees prvide t the city. N ash trees have been planted in the city since We als partnered with gvernment agencies and met with lcal utilities and ther cities t assess the threat f EAB. Residents f St. Luis can see a map f mst ash street and park tree lcatins n the web site shwmtrees.mytreekeeper.cm/ The site was develped by Davey Resurce Grup. Clicking n the small green bug icn will highlight ash lcatins.

2 Ash and EAB Facts: Updated inventry data indicate there are apprximately 14,000 ash trees alng St. Luis streets making it the mst cmmn species and cmprising 17% f all street trees. There are apprximately 450 ash trees in the mwed and manicured areas f nine f ur larger city parks, plus an additinal 1000 in Frest Park. (Frest Park is develping a separate respnse plan.) There are thers in smaller parks and publicly wned wdlands and natural areas. Ash trees are als fund n privately wned residential sites, campuses, cmmercial prperties, and in privately held wdland settings. Additinally, ash trees are fund n sme f the vacant prperties thrughut the city and near verhead utilities. EAB will kill all unprtected ash trees. The number f ash killed each year will rise dramatically sn after the pest invades an area. This is verified with experience in many ther cities with EAB infestatins. Dead ash trees becme extremely Ash Mrtality Curve indicating tree lss each year after EAB dry and brittle mves in t an area. EAB has likely been in St. Luis fr 3- creating high risk. 4 years. Ash and EAB Cnsideratins: The first cities t deal with EAB cast aside large scale cncerns and planned t simply remve trees as they died. They learned the hard way that they culd nt keep up with the munting numbers f dead trees n their hands. Pr strategies in ther cities created issues related t budgeting and public pinin. The Residential street lined with dead ash trees in 2012 cst f dealing with EAB is high, but the cst f nt dealing with it is even higher.

3 The Frestry Divisin cmmissined a study in 2009 that measured the benefits prvided by St. Luis' street trees. The study indicates that ash trees n St. Luis streets prvide annual benefits f $600,000 per year. Benefits include strm water reductins by capturing water in the tree canpy, shading and cling, air quality imprvement, and increased prperty values. A strategy which includes the prtectin f viable ash trees, the remval f ther ash trees, and replanting, will take a large effrt t deal with bth public and privately wned ash trees. The City will be a respnsible steward f publicly wned ash trees and prvide timely and relevant infrmatin t its citizens s that they are infrmed and prepared t deal with EAB. A prject f this size will need mnitring, crdinatin, and the transfrmatin f plans int actin. The City s Frestry Divisin will cntinue t seek assistance and partnerships with researchers and ther municipalities t ensure that its strategy is utilizing the mst current and best tls available ver time. Additinally, it is imprtant t understand that the lss f ash trees must be dealt with as a "new and cntinuing strm" while current critical frestry services will need t cntinue. Dealing with EAB has ften been referred t as the ice strm that lasts fr years. With gd planning and implementatin f a crdinated strategy, the impact can be limited t a temprary lss in tree canpy, with minimal risk t the general public. The City f St. Luis Respnse: Sme trees will be prtected with chemical treatments, but mst will be remved ver a five-year perid. With such a large scale remval f trees, the City will give strng cnsideratin t replanting enugh trees t cmpensate fr the impact f the lss f s many trees. The ideal gal is zer net lss f tree canpy. Treatment and Cntrl - Develp pririties abut which trees are the mst ecnmically feasible t treat and prtect. Frestry Divisin is planning t treat abut 1,000 ash trees that are 13 inches in diameter and larger that are in gd r better cnditin. This represents abut 7 percent f the ash street tree ppulatin. Treatments will be made

4 with a btanic injectable insecticide that is derived frm neem seeds. This rganic pesticide is effective and prvides a high degree f safety fr residents. Treatments are effective fr tw years and then need t be re-applied fr the remaining serviceable life f the tree. Treatments will begin during May f One-half (500) f ur street tree candidates will be treated the first year and the ther half will be treated the next year. Selected park trees will als be treated. Frest Park has an aggressive plan t prject its healthy ash trees as well. Residents with healthy ash street trees that d nt meet the Frestry Divisin treatment criteria can apply fr a n-cst tree permit t treat the tree at their expense. Tree Remval - Priritize and schedule trees t be remved. Apprximately 2600 ash trees will be remved each year fr the next five years. Remvals will begin in July f 2016 and cntinue fr the next five years. Treatments and remvals will begin in areas clsest t the riginal EAB discvery. Infested trees need t be remved as quickly as budgets allw as they will die within 2-3 years f being infested. Dead ash becme extremely brittle and create a public safety risk. Tree mrtality rates will increase rapidly each year and will likely peak in apprximately 6-8 years. Rather than waiting fr mrtality rates t reach levels that cannt be managed, mst cities find it's best t preemptively remve trees, even befre they decline. An aggressive remval prgram f untreated trees will insure public safety and reduce the need fr emergency remvals. EAB traps have been placed in 40 lcatins thrughut the city annually t mnitr the lcatin f infestatins. Inspectins by staff and reprts frm the public will assist in assigning areas where ash tree remval will be scheduled.

5 Re-planting and Recvery Re-planting will achieve cmplete replacement f all ash trees remved. Replanting will utilize aldermanic funds that have histrically been used fr tree planting. Many aldermen have increased funds cmmitted t tree planting in their wards. The City f St. Luis is cperating with a lcal nn-prfit, Frest Re-Leaf f Missuri t secure tree planting grants and prvide assistance with replanting and recvery effrts. A palette f apprximately 40 species will be utilized fr replacements. Educatin and Outreach Create a plan fr cmmunicating effectively with staff, elected fficials, the public, and the media. Tree issues can be emtinal with a large amunt f public interest. Facts and sund strategy will insure a sund prgram f treatment, large scale remvals, and replacements. Web site updates are underway t educate residents abut the city s EAB strategy and t prvide infrmatin fr residents t make infrmed decisins abut treating trees n private prperty. Frest ReLeaf will develp a neighbrhd utreach prgram t keep residents abut EAB activates in the area. Urban Wd Utilizatin Explre wd utilizatin markets t encurage highest and best use f ash wd. While lcal sawmills will likely have little interest, small scale custm sawmillers may have a use fr the millable lgs. With adequate funding, the city will explre the purchase f a small sawmill t make use f this resurce. Smaller pieces will be chipped and cmpsted r made in t mulch and made available t the public. Prper milling and chipping will nt spread the insect. All state and federal regulatins abut quarantined wd will be fllwed.