The Hastings-on-Hudson Street Tree Inventory engaged village residents in the creation of a dynamic database to facilitate caretaking of publicly-owned trees. One hundred volunteers served as neighborhood tree stewards receiving basic training in tree identification and observation collection. Around their blocks, the stewards recorded data on species, location, size, condition, and planting spaces. Analysis informed a planting and green infrastructure protocol for the village towards encouraging the evolution of a healthy and safe urban forest.
The Hastings-on-Hudson Community Street Tree Inventory
I began volunteering my services as a certified arborist in my hometown of Hastings-on-Hudson, New York to help ensure that future generations enjoy the tree-lined streets that I grew up on. I discovered that the village had an aging population of mature trees and no clear strategy for regeneration. Some streets were entirely devoid of trees and many tree pits had been filled with asphalt. I realized that I could contribute to a solution by conducting an inventory of trees and planting spaces. Some of my friends offered to help me, and the idea was born for guiding a volunteer-driven inventory that aimed to engage residents in learning about trees while creating a dynamic database for urban forest management.
Everything kicked-off on Arbor Day 2012 with a call for volunteers to help the Village Tree Board to conduct an inventory of street trees in their neighborhoods. I created and hung posters in shop windows downtown and posted announcements on the village web site. Residents were invited to attend two training sessions to learn about street trees and how to identify the trees on the blocks around their home.
I provided volunteers with basic instruction in tree identification for common trees and for recording specific criteria: location, size and type of planting space, tree diameter at breast height, presence of overhead wires, and noteworthy field observations. I made tree identification training materials, a data sheet, and basic guidelines to follow to assure continuity of data and coverage of all 33 miles of streets. The training sessions were held in the library and broadcast repeatedly on local television. I answered questions via email and made field visits by appointment. We had a range of teams from two young brothers to two grandparents.
I emphasized that it should be fun and that we can correct any mistakes. Participation required no prior experience to participate, only enthusiasm and a partner who was not part of the initial volunteer pool that attended the workshops. I thought that this strategy would enable greater participation and secure more territory coverage. It worked! We began the initial period of data collection during the month of May in 2012 with 50 teams.
Several residents served double-duty by inventorying multiple blocks and assisting in the distribution, collection, and processing of 77 neighborhood inventories. One volunteer remarked that she had never suspected that there were so many things to know about street trees. People enjoyed getting familiar with the trees and having a good reason to walk around their neighborhood. Most volunteers signed-on to be notified for future activities.
With help from a New York State Department of Conservation Urban Forestry Grant we completed the inventory over the summer of 2013 with the recording of tree and planting space locations in the global positioning system. On October 1, 2013, the village received the street tree inventory, an inventory report, and a companion booklet.
The Village-of-Hastings Street Tree Inventory Report provided analysis of the collected data and i-Tree calculations. Within the village’s right-of-way 1036 trees and 1217 planting spaces were inventoried. The stocking level of street trees to available planting spaces for inventoried streets is 45.98% of full stocking. Seventy-one different species were represented with Norway Maple (22.20%) and Callery Pear (10.33%) occurring most often. The estimated annual benefits as calculated by US Forest Service i-Tree software are $149,594, or $144.40 per tree, and replacement value of all inventoried street trees was $6,963,406. At the Board of Trustees meeting the mayor commented that the trees would be expensive and difficult to replace.
The Street Tree Companion, presented village officials with a narrative of the inventory process and a reference for street tree planting and for employing new green infrastructure. I defined the inventory as a tool for efficiently managing street trees while encouraging tree health, safety, and beauty. I included a planting strategy based on analysis of data collected on species diversity and a right-site for the right-tree philosophy. The village manager had suggested in a meeting that I provide a list of trees that he could choose from for future tree planting projects. Later he would point out that he never thought it would be so complex.
For trees to make the list they had to increase population biodiversity and be compatible with site conditions. Trees had to have had success of cultivars in similar communities in New York State and be available in the regional marketplace. Trees were divided into three categories: trees for small spaces with restricted rooting area and under utility wires, trees for medium spaces or tree lawns with no overhead utility wires, and larger trees for open spaces and parks.
I proposed that the village adopt a biodiversity rule of thumb whereas new trees would a contribute to goals of a total population of no more than 30% of trees in the same family, 20% of the same genera, and 10% of the same species. Trees with high populations like Norway Maple (22.20%) and Callery Pear (10.33%) were removed from the list of potential candidates.
The lists included a general mature canopy size and notes about habit, shape, flower, and benefits. The lists intended to be a guideline and updateable with changes in stocking percentages and evolution of the marketplace. In November, 2013, the village planted three Cercis canadensis, three Crataegus viridus ‘Winter King’, and three Malus spp ‘Adirondack’ from the lists. We are organizing the planting of six trees in tree pits downtown for the fall.
This moment is a waypoint for the urban forest. The inventory fulfills the first requirement for state funding towards future green infrastructure. New village improvements could include permeable pavements, structural soil, and stormwater infiltration. I used illustrations to help both officials and residents to visualize how these materials function to provide both sidewalk stability and increased available area for successful tree rooting in planting spaces downtown. Construction details demonstrated pervious forms of concrete and asphalt.
This inventory can help the village save money through planting appropriate trees for site conditions and tracking cyclic tree pruning. Continuing work with the village includes expanding the web site to include a champion tree registry and a pattern study of tree pits in two square blocks to facilitate conversation in a collaborative community design process.
The timing of the tree inventory was critical with an influx in damaged street trees due to repeated extreme weather and Hurricane Sandy. Residents were made aware of invasive threats such as the Asian Long-Horned Beetle and the Emerald Ash Borer and the importance of reporting sightings. Having volunteer tree stewards as “eyes on the street” provides fast, real-time response to these challenges and to any conditions noteworthy for maintenance. The inventory provides a factual basis for decision making and will assist the Village Tree Board to update the Village Tree Ordinance. Participants offered to help water new trees.
The Hastings-on-Hudson Street Tree Inventory was a springboard for community involvement in the caretaking of their urban forest. The trees inventoried are ecosystem service neighborhood powerhouses: improving air quality, reducing greenhouse gas emissions, cooling streets in the summer, reducing storm water runoff, and encouraging activity in outdoor public spaces. This project was the work of a student who volunteers on the Village Tree Board and with help from a university professor, a PhD, New York State, and lots of friends.