Portland Parks & Recreation’s (PP&R) Urban Forestry Team reminds the community that when temperatures soar, extra care is needed to ensure the well-being of Portland’s beloved trees. Not only are the trees a vital part of the city’s aesthetic charm, they also play a critical role in combating climate change and provide essential shade and habitat. Trees are an investment with long-term benefits; maintenance and ongoing care can help ensure their longevity.
Hydration is key, not just for humans, but for trees, too, in order to survive summer heat. During extended periods of high temperatures, it’s important to water trees adequately. Provide a deep, slow watering at the base of the tree to ensure moisture reaches the roots. Water in the early morning or late evening to minimize evaporation. For younger trees, consider using a five-gallon bucket with several holes drilled in the side at the bottom of the bucket. Fill the bucket and let the water trickle into the soil. Fill the bucket three to four times per tree.
Applying a layer of organic mulch around the base of trees can greatly benefit them. Mulch helps retain soil moisture, suppress weeds and regulate soil temperature. Make sure the mulch is spread evenly and keep it three inches away from the trunk of the tree.
Young or newly planted trees may need additional protection from the sun’s intense heat. Use a shade cloth or burlap to create a temporary shade structure that reduces sun exposure. Remove the shade structure once the temperature drops.
Watch for signs of heat stress such as wilting, yellowing leaves or premature leaf drop. If the signs are present, take action immediately by providing extra water and care.
Different tree species have varying tolerance levels to heat and drought. Understanding the specific needs of the trees in your area can help you tailor an effective care routine. Even drought tolerant trees need water when they are young (in their first three to four summers).
Finally, during heat waves, avoid pruning trees as it can further stress the tree. For a comprehensive guide on tree care throughout the year, visit portland.gov/trees/tree-care-and-resources.