Tree Selection and Stock: Navigating Landscape Objectives
When it comes to selecting, planting and growing trees in urban environments, Benjamin Franklin's memorable idiom, in reference to fire prevention, "An ounce of prevention is worth a pound of cure" is worth consideration.
We have all seen, at one time or another, figurative and literal fires involving trees in relation to lack of diversity, physical threats and living pests as well as pathogens. Adopting an approach focused on biological needs and functions of trees can help mitigate threats while assuring long term successes in our work. Let's examine the objectives, variables and strategies that make up this approach.
As with soil, the sustainable urban forest involves building on a strong foundation with appropriately selected trees. The planting site should be also considered, modified and sometimes even redesigned, when possible.
The following point merits repetition: The investment we spend on setting the site up for success, will save us the effort intervening and replacing trees frequently, in perpetuity.
This week, we look at selecting, planting and growing urban trees as a process. This process starts with a solid understanding of the planting site, its potential, its limitations and its possibilities for remediation. Once a planting site can receive trees, the next step involves selecting species that are adapted to grow and thrive in this context. Lastly, once we arrive at a species decision, we move to selecting the individual tree, taking into account availability and production standards in the nursery.
This week's reading will focus on site assessment, species selection and a brief introduction to selecting nursery products. We will, however, continue a more in-depth discussion on nursery stock and practical considerations with Barcham Tree'sLinks to an external site. Keith Sacre, a little later into the course, on or around November 15th- stay tuned for more details!
Learning Objectives
By the end of this topic, you should be able to:
Understand objectives that drive tree planting decisions in cities
Identify variables that must be considered when planning for tree planting operations
Recognize planning approaches for tree planting, that can prevent long term problems and failures
Be aware of strategies and resources that can assist in tree planting endeavours
Topic Readings
Required Readings (Will reinforce course concepts but not covered on exam material)
Bassuk, N. (2017). Site Assessment: The Key to Sustainable Urban Landscape Establishment. Routledge Handbook of Urban Forestry. Routledge, London, (pp. 293–308) (Course textbook).
Sjöman, H., Hirons, A., and Sjöman, J.D. (2017). Criteria in the Selection of Urban Trees for Temperate Urban Environments. Routledge Handbook of Urban Forestry. Routledge, London, (pp. 339–362) (Course textbook).
Looking to get up to speed? Consider this optional reading for more background context and terminology.
Lilly, S.J. (2010).ISA Arborists’ Certification Study Guide. International Society of Arboriculture, Champaign IL (Chapter 6 - Tree Selection).
Want to dive a little deeper?
Petter, J., Ries, P., D'Antonio, A, and Contreras, R. (2020) A Tree Selection Survey of Tree City USA Designated Cities in the Pacific Northwest.Arboriculture & Urban Forestry. 46 (5): 371-384.
Petter, J., Ries, P., D'Antonio, A, and Contreras, R. (2020) How Are Managers Making Tree Species Selection Decisions in the Pacific Northwest of the United States?Arboriculture & Urban Forestry. 46 (2): 148-161.