Repurposing Urban Tree Wood into Play Structures

Do you wonder what to do with leftover wood from a tree care operation? Are the logs interesting, or massive, and are they free from decay? Perhaps the child in you or nearby sees this material serving a new purpose in furniture or a fixture or a play structure. Play structures can lie along a spectrum from primitive to elegant in nature. They can be simple, or intricate, or somewhere in between. Leftover wood you have available may offer a material possibility if you have a way to shape it to your needs. Perhaps that item you want is not available on the market, or it may be expensive to purchase, yet within your ability to prepare.

Stools created from sections of logs are a simple reuse of tree wood in a playground setting. Photo: Scott Sjolander, Penn State Extension.

Among simple ways to repurpose urban tree wood are as basic seating or as natural elements that encourage exploration. Logs could be cut into simple stools providing a resting place, or seats for an outdoor classroom. Longer logs laying on their sides could act as benches to sit on, or as an element in a play area for children to use as their imagination directs, whether as a balance beam, an elevated lookout, or even a hiding spot for a game of hide and seek. More skilled woodworkers might wish to take the logs and mill them into lumber for more intricate play structures.

Children at work exploring. Simple playground structures can incorporate natural materials into designs to encourage learning while playing. Photo: Katie Nowland, Buhl Park, used with permission.

Wood Durability and Service Life

How long will you need this creation to last? Planners label such lasting durability as service life. Different woods vary in durability depending on the species of tree they come from, the degree of decay or infestation from within or the environments they are exposed to. A species may produce wood that is durable in the northern United States, but it may perform poorly under tropical or marine conditions. Despite common expectations, wood density and other physical characteristics do not greatly determine pest or decay resistance. Many heavy and dense hardwoods show superior resistance, but this quality reflects their relatively high extractive content (e.g. resins, waxes) rather than greater wood density.

Decay and insect resistance can vary according to the position in the heartwood from which an item of wood is taken. In some species, the resistance of the outer heartwood increases greatly from the upper to the lower trunk. Decay resistance usually varies from the more resistant outer heartwood layers toward the less resistant center of the tree. We see this from hollow trees standing in the landscape.

Despite the variability of wood’s performance, texts usually consider species such as white oak (Quercus alba), black locust (Robinia pseudoacacia), and Osage orange (Maclura pomifera) to be very durable, while species including Tree of heaven (Ailanthus altissima) are considered very susceptible to decay and failure. It is important to select logs from durable species with little or no decay that are structurally sound. Logs used as structural components in projects should be inspected closely before use and should meet structural requirements spelled out in professionally engineered designs. Always consult a wood technologist or other expert to be sure of what you have and how it would perform in meeting your needs before starting your project.

Another option for wood reuse is to have logs milled into lumber that can be used to build a more intricate playground structure. Photo: Scott Sjolander, Penn State Extension.

Resources

Department of Defense Education Activity. 2011. Education Facilities Specifications. 4-6c-E-Outdoor_Play_Areas-ES-MS. Space Types & Requirements. 21^st Century Schools.

Factor, J. 2004. Tree Stumps, Manhole Covers, and Rubbish Tins: the Invisible Play-Lines of a Primary School Playground. Childhood 11(2): 142-154.

Higley, TL. Comparative Durability of Untreated Wood in Use Above Ground. International Biodeterioration & Biodegradation 35(4): 409-419.

Kaiser, J. 1998 Osage Orange Made its Name as Bow Wood. Wood & Wood Products 103(12): 36. Reprinted online at Woodworking Network (2011).

Olsen, H. and E Kennedy. 2020. Safety of School Playgrounds: Field Analysis From a Randomized Sample. Journal of School Nursing 36(5): 369-375.

Pollet, C., B. Jourez, and J. Hebert. 2008. Natural Durability of Black Locust (Robinia pseudoacacia L.) Wood Grown on Wallonia, Belgium. Canadian Journal of Forest Research 38(6).

Spiegal, B., T.R. Gill, H. Harbottle, and D.J. Ball. 2014. Children's Play Space and Safety Management: Rethinking the Role of Play Equipment Standards. SAGE Open 4(1):1-11.  

Szekely, I. 2015. Playground Innovations and Art Teaching. Art Education 68(1): 37-42.

Tang, A.M.C., P.P.L. Chu, M.W.K. Leung, L.M. Chu, and W.H. Liao. 2016. Evaluating Wood Strength Properties of Subtopical Urban Trees Using Fractometer II. Journal of Topical Forest Science 28(3):249-259.

Urban Wood Network. 2019. The Urban Wood Toolkit. 2019. 22 pp.