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4.10 SR 06-03-2024The Elk River Vision A welcoming community with revolutionary and spirited resourcefulness, exceptional service, and community engagement that encourages and inspires prosperity Request for Action To City Council Item Number 4.10 Meeting Date June 3, 2024 Prepared By Tim Sevcik, Street and Park Superintendent Item Description Emerald Ash Borer Management Plan Reviewed by Justin Femrite Cal Portner Tina Allard Action Requested Approve, by motion, the Emerald Ash Borer Management Plan. Background/Discussion Staff and the City Council discussed the draft EAB Management Plan in a Regular Meeting Work Session on March 4 and April 15, 2024. Through these Work Sessions, staff and the Council modified and revised the draft plan and initiated a communication plan for members of the public. An open house was held on Monday, May 6, 2024, at City Hall to solicit input from the public on this draft plan. Based on input from the public and comments provided by the Council at the April 15, 2024, Regular Meeting Work session, staff recommends adopting the EAB Management Plan with implementation beginning in the fall of 2024. Financial Impact None Mission/Policy/Goal Meet changing needs - Agile Attachments 1. EAB Management Plan Page 45 of 464 1 Emerald Ash Borer Management Plan Policy Page 46 of 464 2 City of Elk River Emerald Ash Borer Management Plan Purpose The City of Elk River has determined the most appropriate management approach for emerald ash borer (EAB) is the systematic removal of ash trees on public property. The objectives of this plan are to educate the public on the effects of EAB, maintain public safety through timely removals of ash trees, minimizing the financial impact to the city by utilizing a systematic approach to treatments, and lowering the risk of future tree canopy loss through a diversified urban forest. Introduction Emerald ash borer (EAB), otherwise known as Agrilus planipennis, is native to eastern Asia. This insect was discovered in the United States in 2002 and has since spread to 36 states including Minnesota in 2009. In Minnesota, EAB has spread rapidly to 50 counties and has already killed millions of ash trees with some cities reporting a complete loss of all ash trees within five years of EAB becoming established. EAB was first identified in Elk River in 2023; however Minnesota Department of Agricultural staff determined it has likely been present since 2018 and is already widespread throughout the city. All species of ash (Fraxinus) trees native to Minnesota are susceptible to infestation by EAB. EAB is spread by adult beetles laying eggs on the bark of an ash tree which hatch into larvae that bore into the tree. The larvae tunnel into the phloem layer of the tree, just under the bark and disrupt the movement of water and nutrients, eventually killing the tree. The adult beetles emerge in the spring and can travel at least a half-mile on their own; however EAB is spread much faster through the movement of ash materials such as firewood, brush and logs. A tree inventory conducted in Elk River in 2013 found 9.2% of all trees within the city are ash with 9.1% of all public trees and 10.1% of all private trees being ash. Based on this survey, it is estimated that there are approximately 1,000 publicly owned ash trees in public rights-of-way, city facilities, and maintained areas of parks; this survey approximates the total ash population within the city at 4,800. Administration The City Administrator will be responsible for administering and implementing the provisions of this plan and keeping the City Council updated. EAB Identification Signs and symptoms of EAB include: ▪Bark splitting ▪Vertical fissures on bark Page 47 of 464 3 ▪Galleries exposed under bark splits ▪Blonding of the bark ▪Serpentine galleries and “D” shaped exit holes ▪The presence of EAB or larvae ▪Canopy dieback ▪Begins in the top one-third of canopy ▪Progresses until the tree is bare ▪Increased woodpecker activity ▪Sprouting of epicormic shoots from the base of the tree Management Strategy Treatment for EAB consists of two primary methods, chemical treatments to prevent ash trees from becoming infested and removal ash trees. Chemical treatments can be further broken down into three primary categories; soil drenches, stem injections, and granular treatments. Of these, granular treatments and soil drenches can be done by the property owner; however the effectiveness of these treatments is limited and both of these treatments can have negative impacts on groundwater, stormwater, and non-target species. Stem injections have shown to be effective for up to three years; however these treatments are cost prohibitive on a large scale with current estimates ranging from $7-$11 per diameter inch of stem at 4.5 feet above the ground and must be conducted every three years to protect the tree. Due to the financial unfeasibility of chemical treatments for publicly owned trees, this management plan will focus on the physical removal of ash trees. The number of public trees removed in any given year will be dependent upon the amount of human and financial resources available. The Street and Park Maintenance Divisions will conduct removals of publicly owned trees as time allows. Tree removals will generally take place from September to March each year. This period ensures that adult beetles have already emerged and transporting of infested wood will not further spread EAB to other areas of the city. Street and Park Maintenance Division staff will work systematically throughout the city conducting removals of ash trees. Based on population growth models for EAB, it is anticipated that 80% of ash trees will die within the next 4-6 years throughout the city which requires an average removal rate of 175-225 public trees per year. Due to this condensed timeline and the hazards posed to public and private property from dead trees, staff will work through neighborhoods removing all public ash trees regardless of their current infestation status. This approach will be the most cost effective while ensuring the necessary staff and equipment resources are available. Public trees are determined to be trees located within public road rights-of-way, city owned stormwater ponds and outlots, city campuses, and city parks. Staff will utilize plat documentation and measurements to determine the edge of the road rights-of-way and determine if the tree is public; trees will be determined public if all or part of the tree’s stem is within the right-of-way. Residents, at their own expense, may hire a surveyor to mark their property boundaries and determine tree ownership if they dispute the city’s assessment. Page 48 of 464 4 Trees located on city campuses and active use areas of parks will be removed, while trees in city outlots, stormwater treatment ponds and natural areas of city parks will be evaluated for their potential to cause damage to public or private infrastructure. If a tree in these areas is identified as a potential hazard to a target it will be removed; trees without potential targets will be left untreated to provide wildlife habitat and to be recycled into the soil. Removal of ash trees will be conducted in three phases; removal of tree, stump grinding, and restoration. During removal, staff will work through a neighborhood felling ash trees, loading brush and logs and transporting materials to the city compost site. This activity may require temporary traffic control and/or road closures to allow staff a safe work zone until the tree is felled and all material is removed. Stump grinding will be conducted by staff as time permits and may be done at any time during the year. Restoration will consist of black dirt and seed appropriate to the conditions. In areas where private landscaping, pet fences and irrigation systems are within the public right-of-way, staff will work to minimize impact to the landscaping during the removal and stump grinding process. The city is not responsible for damage to private landscaping within the right-of-way and it is the homeowner’s responsibility to restore any disturbed landscaping because of ash tree removal. Tree Replacement Due to the volume of public trees anticipated to be removed as a result of EAB, the city must focus its efforts on tree replacements in areas of greatest need. Trees on city campuses and public parks will be the priority for replacement to ensure aesthetics of public facilities and provide shade to the public. Tree replacement along public rights-of-way may be conducted as time and resources permit. Establishment of trees in public rights-of-way will be the responsibility of the adjacent property owner. The city will not conduct tree replacements in city outlots, stormwater ponds, or natural areas. These areas will be allowed too naturally regenerate. Replacement trees will consist of 1-1.5-inch diameter bareroot trees consisting of a variety of species to establish a more diverse canopy able to resist any future disease and insect pests. Tree species include hybrid American elm (sp.), white oak (sp.), maple (sp.) hackberry, Kentucky Coffee, American linden (sp.), river birch, honey locust, Ohio buckeye, ginkgo, black cherry, black walnut, butternut, northern catalpa, northern redbud, shagbark hickory, and bitternut hickory. These tree species meet current and projected frost hardiness zones for central Minnesota according to the University of Minnesota, Forest Resources Department. Private Trees The City of Elk River does not intend to treat or remove ash trees located wholly within private property, removal of these trees is the responsibility of the property owner. The city may inspect and conduct abatement of any nuisance trees in accordance with Chapter 46 Page 49 of 464 5 Section 46-34 of the city ordinance. Nuisance trees on private property are further defined in Chapter 82, Article II, Section 82-30 through 82-40 of the ordinance. In accordance with these sections, property owners are responsible to abate any trees that are dead, diseased, or otherwise not maintaining foliage on more than 50 percent of the tree during the growing season. In the event abatement is not conducted, the city may abate the tree to prevent further spread of EAB. The City of Elk River, at the direction of the Council, may establish master contracts for ash tree injections and/or removals. These contracts, if determined by the Council, may provide for bulk treatment pricing that could be extended to privately owned ash trees to reduce the cost to homeowners. Additionally, at the direction of the Council, the City may apply for grant funding to support the city’s EAB program. Through these programs, there is the potential for the city to provide assistance to private property owners for ash tree abatement. Wood generated from the removal of EAB infested ash trees may be disposed of at the Elk River Compost Facility located at 19000 Proctor Road, Elk River, MN 55330. Compost site passes are available in person at City Hall or online at Compost Site | Elk River, MN - Official Website (elkrivermn.gov). Residents are required to follow all compost site requirements when disposing of any tree or yard waste. Contractors may dispose of tree waste in the compost site only if performing work on Elk River residents’ property and utilizing the compost site pass of the property owner to gain access to the site. Materials from outside of Sherburne County are not authorized. Communication Communication and education of the public are key components of managing the impact of EAB. Public information will be available to residents through the City’s website, social media sites, newsletters, a public open house, and the local newspaper. Residents can also find information about EAB on the following websites: Emerald Ash Borer Program | Minnesota Department of Agriculture (state.mn.us) Emerald Ash Borer Information for Homeowners | Minnesota Department of Agriculture (state.mn.us) Does My Tree Have Emerald Ash Borer (EAB)? (state.mn.us) Ash Tree Identification (state.mn.us) Firewood Information | Minnesota Department of Agriculture (state.mn.us) Page 50 of 464 6 Emerald Ash Borer Management Plan Policy History Adopted by:On (date)Item # Page 51 of 464