CITY OF MORDEN ASH STRATEGY. Emerald Ash Borer Management

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1 CITY OF MORDEN ASH STRATEGY Emerald Ash Borer Management Parks Department December 2017

2 Table of Contents 1.0 Executive Summary Inventory, Monitor and Assessment Public Education and Communication Removals Treatment Tree Planting Wood Waste Disposal Management Options for EAB Management Option 1 Do Nothing Management Option 2 Treat All Management Option 3 Hybrid Recommendations Appendix A: Option 1 Do Nothing Appendix B: Option 2 Treat All Appendix C: Option 3 Hybrid P a g e

3 1.0 Executive Summary The City of Morden is known as a community with a well treed landscape. This treed landscape, better defined as the Urban Forest, positively contributes to the look and feel of the community. The contributions of the Urban Forest go beyond aesthetics to include storm water reduction, energy savings, air quality improvements, and an increase in property values. As identified in the City of Morden Urban Forest Management Plan (UFMP), public trees in the community provide and average annual benefit of $ per tree. Urban Forestry is identified in the Corporate Plan through the Environmental Action section. Data gathered from a city wide public tree inventory was used in the development of the Ash Strategy. The inventory has 5, 330 trees surveyed to date but does not include the 35 acres of natural woodlot or forested stands. Ash, Linden, Maple, Elm, Hackberry, Oak and Spruce represent leading species. Based on the inventory there are 1, 980 ash trees comprising 37% of the City s public trees. Ash represents the largest number of trees by percentage with Linden second at 15%. The Province of Manitoba conducted an ash tree inventory to estimate the distribution of ash across the province. Rural communities such as Winkler and Carman were part of that inventory. With the information from the provincial survey it can be estimated that approximately 1 ash tree exists per resident. For Morden, an estimated private ash tree component could be close to 6,000 trees. Combined Morden is host to approximately 8,000 ash trees. Emerald Ash Borer has moved into Manitoba. In a news release on December 7 th, 2017 EAB was positively identified in the City of Winnipeg by the Canadian Food Inspection Agency. This invasive species has moved westward from its last know location 700km away in Thunder Bay, where it was identified in June of The beetle may be present but undetected in a community for years before positively identified. The visual signs and symptoms of EAB in ash may only occur several years after the beetle arrives. Given our proximity to Winnipeg, the delays in early detection and the abundance of ash trees, the City of Morden is at imminent risk of hosting Emerald Ash Borer. Once discovered, EAB could destroy all ash trees within 10 years. The City of Morden is fortunate to be able to review plans and strategies from other EAB affected communities to aid in the development of an ash strategy. This information guides Morden s ash strategy towards a proactive and hybrid approach of monitoring, removing and treating ash trees. This hybrid approach ensures selective ash tree protection; preserving annual tree benefits, public safety; identification and timely removal of infected trees, and renewal; tree planting with a selection of non-ash species. The activities and costs outlined in this strategy will start in 2018 and continue to The ash strategy will require annual reassessment with recommendations to council. Operational 2 P a g e

4 information on EAB management activities will be contained in the Parks Department Monthly Report to council starting in December The proposed ash strategy that will guide the City over the next 10 years includes: Inventory, monitoring and assessment Public education and awareness Removals (including stump grinding) Treatments Tree planting Wood waste disposal 2.0 Inventory, Monitor and Assessment The inventory completed by the Parks Department includes the physical location and attributes such as; species, height, diameter, condition, and location. From the inventory, the total number of public ash trees is 1,980 and further divided by 1, 711 green ash (Fraxinus pennsylvanica) and 271 Manchurian ash (Fraxinus mandshurica). Ash trees account for 37% of the total number of public trees inventoried. Map 1: Illustrates the distribution of Ash trees throughout the city as of December P a g e

5 As stated in the Urban Forest Management Plan a standard rule of is applied in the context of tree diversity:30 equaling the percentage of trees from a family group, 20 percent from a genus, and 10 percent from a single species. Based upon the even aged monoculture of ash planted post Dutch elm disease the City is left with a higher than recommended family, genus, species composition. For the last five years the City has used prism traps and lures to monitor for EAB. In 2017, four prism traps with lures were distributed throughout the City. Parks crews maintained and inspected the traps mid and post season. In 2017, EAB was not found in any of the traps. Photo 2: Shows a EAB prism trap Another monitoring and assesment method is by way of branch sampling. Natural Resource Canada, Canadian Forest Service publication Detection of emerald ash borer in urban environments using branch sampling provides methods of how to conduct branch sampling. In a visually non-sympomatic ash tree branch, sampling is a way of detecting EAB larval activity. City of Morden Parks crews will start branch sampling in January A plan is being developed for determining the location and frequency of branch sampling. Sample trees will be recorded in the inventory. Photo 3 &4: Shows branch sampling techniques and early stages of larval activity. 4 P a g e

6 Assessments will occur once EAB has been positively identified. These assessments will look at larval activity and trapped adults to determine the hotspots of beetle activity. With identified hotspots, crews can focus on management closer to the higher population levels. 3.0 Public Education and Communication The City will start immediately with public education and communication on both the beetle and the activities undertaken by the City to manage EAB. Most ash trees occur on private property; therefore, education and communication to the public will be important as private tree management will impact the city s ash strategy. This will also help with decision making for private ash tree owners. The City will employ the following methods as part of the public education and communication portion of the ash strategy: Social Media and Website o Dedicated EAB page under the Urban Forest section of the website and facebook announcements. Private Tree Inventory App o Survey123 is being developed for private residents to identify and map private trees. Community Information Session o Host in person information workshops. Tree Banners o Plastic banners that wrap around trees with important info. Provincial publications o Distribute already printed EAB awareness materials, posters, pamphlets, kid s tattoos, identification tags. 5 P a g e

7 Photo 6: Public education tree banner from Duluth and treatment banner from Minnesota 4.0 Removals When it comes to EAB we understand there is no zero cost option. Dead or dying trees are categorized as high in a tree risk assessment and pose a public safety threat requiring immediate removal. It is also understood that ash is a straight grained wood and has a low moisture content compared to other hardwoods. Once attacked by EAB, water transportation in the sapwood is compromised drying out the wood further. Therefore, the risk of branch or catastrophic (at the base) failure is higher in ash trees. If left defoliated and dead standing, the brittle wood becomes unpredictable for tree removal workers increasing the safety risk to removal crews. From a recent EAB workshop held in Winnipeg, arborist companies have a no climb policy once the infected tree looses 20% of the foliage. Knowing that EAB is immanent and removals of infected trees will be required, the City can take a proactive and systematic approach towards removals before EAB is arrives and before infected trees become unsafe. 6 P a g e

8 Number of Photo 7: The above photos were taken of before and after tree removal due to EAB from a boulevard in Colorado. The systematic approach to removals is to use the condition rating of each tree. Condition rating is based on the ISA standard for Assessing Shade Trees and categorized into Good, Fair, Poor, Dead/Dying. Currently we have 1,535 good condition, 292 fair condition, 55 poor condition and 6 dead/dying. Ash Condition Rating Good Fair Poor Dead/Dying Condition Graph 1: Distribution of ash trees based on condition rating. 7 P a g e

9 Removing the poorer condition trees supports the need to increase tree species diversity, reduce treatment costs for Cottony Ash Psyllid and helps to slow the spread of EAB. 5.0 Treatment There are various treatment options for EAB based on infestation levels and budgets. There are some lessons we can learn from others experiences and recommendations. When EAB was first detected in Windsor, Ontario, large swaths of trees were removed to control the spread. Later this method was proven ineffective. Eradication of EAB is unrealistic and most municipalities have turned to prevention initiatives and measures to slow the spread. EAB affected communities who reacted to trees already infested had fewer options when it came to slowing the spread and reducing the overall impacts. Treatment using a systemic insecticide injection of TreeAzin TM (or other approved pesticides) for protection against EAB has proven to be effective. Treatments can be invaluable in managing the outbreak and spread of EAB by suppressing local populations of the insect. TreeAzin TM, a biopesticide derived from plant extracts, is the chemical used almost exclusively by municipalities. To date it has proven 95-97% effective when injected before the tree reaches pre-determined levels of damage. Photo 5: The above photo shows the comparison of an injected tree and untreated tree. 8 P a g e

10 Determining trees to receive treatment is a combination of the following criteria: Condition Rating o Trees of good health, structure/form, free of insect and disease and damage. o If EAB is present, research shows that success rates are low in trees with more than 30% crown dieback. Size o Trees less than 20cm in diameter are more cost effective to remove and replant. In general, larger trees provide more benefits. Location o Trees in restrictive environments have a lower life expectancy and are more stressed for resources compared to open grown trees with no restrictions. Permanence o Property management and future development plans should be considered in choosing trees for preservation. GOOD CONDITION TREES BY SIZE 0 20cm 20 30cm 30cm Diagram 1: The above diagram shows the number of good condition ash trees by diameter. Trees of good condition and greater than 20cm DBH are candidates for treatment. 9 P a g e

11 6.0 Tree Planting Over the last five years the City of Morden has not planted a single ash tree. This practice will continue with the intentions of planting a variety of genus utilizing the largest possible tree given the space provided. The approved planting list for boulevards contains; maple, elm, and linden as large trees, hackberry, Japanese elm, alder, and birch as medium trees and maple, cherry, lilac, catalpa, and ornamental crab apple as small trees. Parks and natural areas have additional species approved which may have been undesirable boulevard trees based on fruit or traffic visibility. In addition to the boulevard trees listed above park and natural plantings may also include: oak, pine, spruce, balsam fir, poplar, cottonwood, butternut, and black walnut. Prior to the inventory and UFMP the rate of planting was variable based on the number of homeowner requests for boulevard trees and annual work plans by the parks department. City wide planting is now determined annually by the number of removals in the previous year (1:1 ratio), homeowner requests (in advance), capital and operating projects, and voids in the inventory. Given the percentage of ash trees in the community and the threat of EAB, planting of non-ash species will continue. Trees removed in one year will be replanted by the end of the following growing season with priority given to residential boulevards. The city will work with nursery growers to trial new species to increase diversity. The city may consider adding some species from the park and natural areas list to the boulevard list. 7.0 Wood Waste Disposal An EAB outbreak will add to the current tree waste disposal system. It is assumed that disposal will be the responsibility of the City. The City will communicate with the appropriate government agency and follow regulations for disposal. Within the Provincial Emerald Ash Borer Strategy, the following information is provided: Options to consider for disposal: Disposal via burning or burying: This would likely have to be done at designated municipal waste disposal sites. The CFIA federal regulations, as well as Manitoba s, would have to be adhered to. It would be preferable to establish these sites within federally regulated areas, but if the site was outside of the federally regulated area, federal requirements contained in CFIA s Plant Protection Directive, Phytosanitary Requirements to Prevent the Introduction Into and Spread within Canada 10 P a g e

12 of the Emerald Ash Borer, Agrilus planipennis Fairmaire (D ) would have to be met. Regular inspections by Forestry Branch officers or inspectors would be necessary. Chipping: A large chipper or tub grinder could be purchased or rented by the province or municipality, and removed trees could be chipped immediately at the site or at a loading site. In wild and riverbank areas, trees could be felled and then burned at the site as is done with Dutch elm disease infested trees in similar areas. 8.0 Management Options for EAB Trees in our parks, along our boulevards and surrounding our homes help to make Morden an attractive and vibrant community. It is estimated that once EAB is found in a community all ash trees could die within 10 years. For Morden, losing 37% of the treed canopy will have social, economic and environmental impacts. The threat of EAB to our Urban Forest health is significant and a hybrid proactive approach of monitoring, public education, removals, treatment and planting should be considered. For comparison, three management options were explored. Option 1 is to do nothing, wait for the arrival of EAB and react by removing trees as they decline. Option 2 involves removing a small number poor and fair condition trees and treating the rest by way of systemic insecticide injection. Lastly, Option 3 is a hybrid approach of annually removing a small percentage of trees, treating 50% of good condition larger diameter trees, replacing removed trees with non-ash species while spreading the program costs over 10 years. 8.1 Management Option 1 Do Nothing As visual symptoms occur, such as foliage dieback, trees in public spaces must be removed. After 10 years it is estimated all 1,980 ash trees will die and require removal. If this option is employed consideration must be taken in terms of the timing, budget and qualified labour available for removals and waste disposal. EAB is slow to start and after a few years ramps up significantly causing a spike in removals over a short period of time. 11 P a g e

13 The above chart, taken from the City of Peterborough EAB Management Plan, illustrates the spike in ash tree mortality. Operationally city crews would wait for visual symptoms or positive identification to occur and start removals based on tree risk assessment, public safety, and potential infrastructure damage. This option has zero tree benefits after the 10 year term. 8.2 Management Option 2 Treat All Prior to the treatment of ash trees, a total of 447 poor and fair condition trees would require removal. This would leave 1,533 good condition trees available for treatment. Based on product recommendations ash treatments would be conducted once every two years. This option provides the highest retention of benefits but is also the highest cost option. Annually, 766 ash trees would require treatment. This would leave the City with a 28% ash tree component whereas the goal for a single genus is 20% and single species is 10%. It should also be noted that with the distribution of ash outside the City in neighbouring communities and shelterbelts, the treatment program may be extended beyond the 10 year period. 12 P a g e

14 8.3 Management Option 3 Hybrid This option is considered the middle ground with a combination of removals, treatments and plantings helping to slow the spread of EAB. Treatments are determined through criteria that select the healthiest and largest trees retaining approximately 50% or 768 ash trees. This option allows for a more accurate annual budget estimate and would spread the costs equally over the 10 years. This option has the greatest impact on slowing the spread of EAB. 9.0 Recommendations All of the EAB management options require some level of monitoring and assessment, public education and communication, tree planting and waste disposal. The decisions surrounding removals and treatments play a larger role in the selection of one option over another. When comparing the three options and the associated budgets and cost/benefit, it is recommended that the City of Morden employ management option 3. This hybrid option allows for removal of poor and fair quality trees with retention via treatment of healthy trees. This option helps to slow the spread of EAB, retains annual benefits from select ash trees, reduces 13 P a g e

15 other ash tree pest problems and helps to reduce the percentage of ash to within target levels for species diversity. Table 1: Benefit and Cost of EAB Management Options Option Cost of Option Remaining Ash Tree Remaining Benefit/Cost Annual Ash Benefits Appraisal Ratio Benefits at During Term Value End of Term Option 1 - Do nothing $1,385, $1,131, $0.00 $0.00 Option 2- Treat all $1,505, $2,197, $194, $2,146, Option 3 - Hybrid $1,418, $1,758, $97, $1,071, *average tree benefit is $127 annually *average appraisal value is $1,400/tree 10.0 Plan Implementation Implementation of the ash strategy will begin in A certain level of public education and communication will need to lead any removal activities. At the same time, monitoring by way of branch sampling can occur during the winter months of Branch sampling methodology developed by the Canadian Forest Service will be used and all samples will be tracked using our tree inventory data collection system. In 2018, 155 trees will be removed (6 dead/dying, 55 poor, and 94 fair Manchurian ash). The 155 trees removed in 2018 will be replanted in In 2019 and 2020, 146 fair trees will be removed each year and replanted in the following years. For the remaining program years, 94 trees will be removed annually. Treatment of 20 trees in 2018 will allow staff to become familiar with product use, costs and labour. Initial treatment may also be used to educate and inform the public. A total of 768 trees will be treated every two years. Starting in 2019, the first half will be treated, and in the second half will receive treatment. Outside of the 10 year plan, potential removals will be guided by tree risk assessment considering public safety and operation efficiencies. Annual review of this plan during implementation will be required as will monthly reporting on all EAB management activities. This strategy will also be amended if government regulations arise during the course of implementation. To date no funding has been identified for assistance with EAB management. 14 P a g e

16 Appendix A: Option 1 Do Nothing Year Number of Trees Removed Inventory, Monitoring and Assessment, Number of Trees Treated Treatment Costs Removal Cost Replanting Cost Public Education and Awarness ($) Waste Disposal Yearly Totals ($) $2, $0.00 $0.00 $0.00 $5, $0.00 $7, $2, $0.00 $0.00 $0.00 $5, $0.00 $7, $2, $0.00 $15, $0.00 $5, $3, $25, $2, $0.00 $30, $15, $1, $7, $56, $2, $0.00 $75, $30, $1, $18, $127, $2, $0.00 $150, $75, $1, $37, $266, $2, $0.00 $180, $150, $1, $45, $378, $2, $0.00 $121, $180, $1, $30, $335, $2, $0.00 $15, $121, $1, $3, $143, $2, $0.00 $7, $15, $1, $1, $27, $2, $0.00 $0.00 $7, $1, $0.00 $11, Totals 1980 $22, $0.00 $594, $594, $27, $148, $1,385, (1) 2018 removals are dead/dying and poor condition trees 155, 2019/20 fair condition trees 146, good condition trees less than 20cm dbh. (2) 2018 treatment ahead of detection as a tool for public education, staff training, future cost/time estimates, and proactive approach (3) Planting costs at $300.00/ tree includes stump grinding Planting will not occur for EAB removals, 150 removed trees in 2017 are planned to be planted in EAB Planting will occur on a 1 to 1 ratio. (4)Treatment cost is estimated $5.00/cm, treated every 2 years with TreeAzinTM. Number of treated trees is 50% of good condition 25cm DBH trees. Average DBH of treatment group is 30cm. (5) Removal cost at $300/tree based on average DBH of 30cm. (6) Waste Disposal includes chipping, hualing, burning or grinding at $75/tree (7) Inventory, Monitoring and Assessment cost is only estimated and can be tracked and in subsequent years be adjusted (8) Public Education and Awareness cost is only estimated and can be tracked and in subsequent years be adjusted 15 P a g e

17 Appendix B: Option 2 Treat All Year Number of Trees Removed Inventory, Monitoring and Assessment, Number of Trees Treated Treatment Costs Removal Cost Replanting Cost Public Education and Awarness ($) Waste Disposal Yearly Totals ($) $2, $3, $46, $0.00 $5, $11, $68, $2, $115, $43, $46, $5, $10, $223, $2, $115, $43, $43, $5, $10, $220, $2, $115, $0.00 $43, $1, $0.00 $162, $2, $115, $0.00 $0.00 $1, $0.00 $118, $2, $115, $0.00 $0.00 $1, $0.00 $118, $2, $115, $0.00 $0.00 $1, $0.00 $118, $2, $115, $0.00 $0.00 $1, $0.00 $118, $2, $115, $0.00 $0.00 $1, $0.00 $118, $2, $115, $0.00 $0.00 $1, $0.00 $118, $2, $115, $0.00 $0.00 $1, $0.00 $118, Totals 447 $22, $1,155, $134, $134, $27, $33, $1,505, (1) 2018 removals are dead/dying and poor condition trees 155, 2019/20 fair condition trees 146, good condition trees less than 20cm dbh. (2) 2018 treatment ahead of detection as a tool for public education, staff training, future cost/time estimates, and proactive approach (3) Planting costs at $300.00/ tree includes stump grinding Planting will not occur for EAB removals, 150 removed trees in 2017 are planned to be planted in EAB Planting will occur on a 1 to 1 ratio. (4)Treatment cost is estimated $5.00/cm, treated every 2 years with TreeAzinTM. Number of treated trees is 50% of good condition 25cm DBH trees. Average DBH of treatment group is 30cm. (5) Removal cost at $300/tree based on average DBH of 30cm. (6) Waste Disposal includes chipping, hualing, burning or grinding at $75/tree (7) Inventory, Monitoring and Assessment cost is only estimated and can be tracked and in subsequent years be adjusted (8) Public Education and Awareness cost is only estimated and can be tracked and in subsequent years be adjusted 16 P a g e

18 Appendix C: Option 3 Hybrid Year Number of Trees Removed Inventory, Monitoring and Assessment, Number of Trees Treated Treatment Costs Removal Cost Replanting Cost Public Education and Awarness ($) Waste Disposal Yearly Totals ($) $2, $3, $46, $0.00 $5, $11, $68, $2, $57, $43, $46, $5, $10, $165, $2, $57, $43, $43, $5, $10, $163, $2, $57, $28, $43, $1, $7, $140, $2, $57, $28, $28, $1, $7, $125, $2, $57, $28, $28, $1, $7, $125, $2, $57, $28, $28, $1, $7, $125, $2, $57, $28, $28, $1, $7, $125, $2, $57, $28, $28, $1, $7, $125, $2, $57, $28, $28, $1, $7, $125, $2, $57, $28, $28, $1, $7, $125, Totals 1214 $22, $579, $364, $335, $27, $91, $1,418, (1) 2018 removals are dead/dying and poor condition trees 155, 2019/20 fair condition trees 146, good condition trees less than 20cm dbh. (2) 2018 treatment ahead of detection as a tool for public education, staff training, future cost/time estimates, and proactive approach (3) Planting costs at $300.00/ tree includes stump grinding Planting will not occur for EAB removals, 150 removed trees in 2017 are planned to be planted in EAB Planting will occur on a 1 to 1 ratio. (4)Treatment cost is estimated $5.00/cm, treated every 2 years with TreeAzinTM. Number of treated trees is 50% of good condition 25cm DBH trees. Average DBH of treatment group is 30cm. (5) Removal cost at $300/tree based on average DBH of 30cm. (6) Waste Disposal includes chipping, hualing, burning or grinding at $75/tree (7) Inventory, Monitoring and Assessment cost is only estimated and can be tracked and in subsequent years be adjusted (8) Public Education and Awareness cost is only estimated and can be tracked and in subsequent years be adjusted 17 P a g e

19 Appendix D: List of Approved Trees Large Sized Trees Medium Sized Trees Small Sized Tree Species Common Name BLVD PARK NAT AREA Picea glauca White Spruce N Y Y Abies balsamea Balsam Fir N Y Y Pinus ponderosa Ponerosa Pine N Y Y Larix laricina Eastern Larch/Tamarack N Y Y Acer saccharinum Silver Maple Y Y Y Tilia americana Basswood Y Y Y Acer negundo Baron Maple Y Y Y Acer negundo Manitoba Maple N Y Y Quercus macrocarpa Bur Oak N Y Y Ulmus 'Morton Glossy' Triumph Elm Y Y Y Populus deltoides Eastern Cottonwood N Y Y Populus tremuloides Trembling Aspen N Y Y Populus XACW151 Sundance Poplar N Y Y Species Common Name BLVD PARK NAT AREA Aesculus A. glabra Ohio Buckeye N Y N Celtis occidentalis Delta Hackberry Y N N Betula platyphylla Dakota Pinnacle Birch Y Y N Ostrya virginiana Ironwood Trial Juglans cinerea Butternut N Y Y Juglans nigra Black Walnut N Y Y Ulmus davidiana var.japonica Discovery Elm Y Y N Alnus hirsuta 'Harbin' Prairie Horizon Alder Y Y Y Species Common Name BLVD PARK NAT AREA Cornus alternifolia Pagoda Dogwood N Y Y Syringa reticulata Japanese Tree Lilac Y N N Acer ginnala Amur Maple Y Y N Acer tatarica Hot Wings Tatarian Maple Y Y N Malus adstringens Gladiator Crab Apple Y Y N Elaeagnus angustifolia Russian Olive N Y N Malus spring snow Spring Snow Crab Apple Y Y N Sorbus aucuparia Russian Mountain Ash N Y N 18 P a g e