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| Authors: | Forest Service USDA |
| Year: | 2019 |
| Type: | Resource Update |
| Station: | Northern Research Station |
| DOI: | https://doi.org/10.2737/FS-RU-198 |
| Source: | Resource Update FS–198. Newtown Square, PA: U.S. Department of Agriculture Forest Service, Northern Research Station. 2 p. |