The Schenley Park Tree Research Grove To Grow A More Resilient Urban Forest

In our continued effort to support the urban tree canopy, and to absorb stormwater as it flows through our parks, the Pittsburgh Parks Conservancy is excited to announce The Schenley Park Tree Research Grove. Growing soon on Frew Street near the Westinghouse Memorial and Pond, this new project is planted in partnership with the City of Pittsburgh and Tree Pittsburgh.

Trees, like human beings, are genetically diverse. One of the strongest defenses our urban forest can hope for as an increasing number of diseases and non-native insects threaten at least 60% of our tree canopy is greater genetic diversity.

Most of the trees sold in nurseries, however, are clones. Because of this, a threat to the health of one of these trees could be a threat to them all because they are genetically identical. Our parks are full of mature trees that are thriving, telling us that they have the perfect genetic makeup to survive in Pittsburgh. The Schenley Park Tree Research Grove (affectionately called “Fezziwig Grove” by the project’s benefactor) will provide a space to plant native trees gathered from seed in our parks and identify those that thrive.

Sorting for Resilience

Pittsburgh Parks Conservancy horticulturalists have identified trees which show strong resilience to conditions in our region. Seeds gathered from these parent trees are taken to Tree Pittsburgh Heritage Nursery where they are scarified, germinated, and grown to a two gallon container size. Once they are big enough, the tree will be transplanted into the Tree Research Grove where our horticulturalists will care for the trees and carefully monitor them for disease and deformity.

It will likely take a period of 7-10 years for the trees to fully mature within the grove. For the duration of that time they will mitigate stormwater that would eventually run into Carnegie Mellon University, the Westinghouse Memorial Pond, and Panther Hollow Lake. Each individual tree will remove thousands of gallons of stormwater each year, keeping that water from entering our combined sewer system.

Trees that are unsuccessful will be removed from the grove and transplanted as restoration trees in park woodlands, while those that present as ideal candidates for landscape plantings will be made available to the public at nurseries for future plantings in our region. This will diversify the trees available on the market and ensure that trees that are genetically likely to survive Pittsburgh’s unique weather are available for us all.

Rooting the Grove in Research

The first tree species identified for this research is the yellowwood tree. Yellowwoods are large trees with stunning cascading white flowers in the spring, and yellow fall foliage. Yellowwoods have been a challenging tree to grow in our park landscapes because they become diseased or can’t survive the frost. But we have reason to believe they can do well here and further diversify our tree canopy because there are several older yellowwoods with perfect form in Schenley Park. Our hope is that by collecting seed from these trees we will find a good match for Pittsburgh.

Formal site preparation for this new project will begin in spring 2019, including the installation of the berms and infiltration basins similar to the ones installed uphill in the golf course, and deer fencing. We expect the first plantings of yellowwoods to go in fall of 2019.