PENNSYLVANIA — Nurseries across the U.S. grow over a billion tree seedlings each year for reforestation following timber sales, wildfire and other disturbances. The USDA Forest Service National Center for Reforestation, Nurseries, and Genetic Resources provides technical assistance to Forest Service and partner nurseries to help them produce high-quality, genetically appropriate seedlings. 

Most of these seedlings are intended for rural forests. Yet there’s a pressing need for seedlings suited to urban forests, an area that the RNGR team does not currently cover. That’s why the Forest Service is making new investments in the RNGR program to help connect urban communities with the reforestation pipeline. RNGR is a virtual team, distributed across the United States, and represents all three deputy areas of the Forest Service. Currently the team is composed of employees from State, Private and Tribal Forestry, National Forest System, and Research and Development. 

“Today, the reforestation pipeline focuses on rural landscapes, but the same principles apply to urban forest landscapes,” said Carrie Pike, regeneration specialist with Eastern Region State, Private and Tribal Forestry. “And urban forests bring similar health and environmental benefits for communities. RNGR can help ensure that these efforts are successful and tree planting goals are met.”

Handling tree seedlings requires expertise that may not be supported on tight city budgets. One way the RNGR team is addressing this disparity is by adding an urban nursery specialist position to help provide technical assistance to expand tree planting in urban areas.

Successful urban tree planting means overcoming other hurdles as well, including the fact that the most widely available plant materials aren’t suited to urban forests. In conventional reforestation in rural areas, one- to two-year-old seedlings are ideal. But seedlings need to be larger when planted in urban natural areas, waterways and parks, where native trees mingle with understory shrubs.

Nurseries that do grow trees for urban areas—usually private nurseries and garden centers—tend to focus on a large balled and burlapped stock of cultivars selected for their beauty or resilience in arid urban spaces. Yet these large, expensive trees are far from ideal for urban forests. Intended for planting along roadsides, they generally do not come from native, genetically diverse seed sources.

What’s really needed for planting in the wildland-urban interface are mid-size trees of locally sourced native species. Today, such mid-sized trees are difficult to procure and rarely sold at garden centers. Some cities will purchase small seedlings from state or private nurseries and grow them for an additional year in containers or longer to reach a target planting size. Gravel beds are also used to increase root system size of tree seedlings for planting.

As RNGR partners with nurseries to help produce appropriate seedlings for urban reforestation, they must address challenges like the lack of native tree seed, which is also a common bottleneck for rural reforestation. Urban environments can play a role in innovative solutions that also benefit rural forests. For example, seed from large, legacy urban trees may be readily accessible at cemeteries and local parks, where seed can be collected from the ground. Seed from these areas may be purchased by local nurseries and planted in rural areas.

Another challenge is that education and training are needed in cities where green jobs in the reforestation sector may seem distant and uninviting. To share ideas and build connections, this year’s Northeast and Southern Nursery Conference prominently featured urban reforestation. Sponsored by the State of Pennsylvania and the RNGR program through an agreement with Western Forest Nursery Conservation Association, the conference was held during July in State College, Pennsylvania.

"The Forest Nursery conference was an invaluable opportunity to connect with other nursery managers in our region, and to share ideas and troubleshoot common challenges in our specialized field. I really valued hearing about new initiatives and updates on best management practices during the conference sessions and seeing hands-on operations during the field day,” said Megan Palomo, Heritage Nursery director, Trees Pittsburgh.

The keynote speaker was Siyabulela “Siya” Sokomani, founder and owner of Nguni Nursery in Cape Town, South Africa, which produces native plants and trees for urban and rural environments. Staff from the RNGR program developed a pre-conference tour for Sokomani, with help from staff at the Northern Research Station field station in Baltimore, Maryland, to learn how communities accomplish reforestation in the urban context. Sokomani and RNGR staff also visited city employees in Philadelphia to learn more about TreePhilly and the city-run Greenland Nursery as well as other for-profit and non-profit nurseries that serve the region.

The RNGR team is also expanding to include three new full-time national specialists for nursery pests, urban and tropical nurseries. The team continues to work across deputy areas, and with partners, to help improve reforestation capacity across the U.S.