Attributes / relations provided by
♦ 1Wood Janka Hardness Scale/Chart J W Morlan's Unique Wood Gifts
♦ 2Forest Inventory and Analysis DB version 5.1, May 4, 2013, U.S. Forest Service
♦ 3National Geographic Magazine - May 2016 - Yellowstone - The Carnivore Comeback
♦ 4Ben-Dov, Y., Miller, D.R. & Gibson, G.A.P.
ScaleNet 4 November 2009
♦ 5Jorrit H. Poelen, James D. Simons and Chris J. Mungall. (2014).
Global Biotic Interactions: An open infrastructure to share and analyze species-interaction datasets. Ecological Informatics.
♦ 6New Zealand Institute for Plant & Food Research
Plant-SyNZ™ database♦ 7Tamiasciurus douglasii, Michael A. Steele, MAMMALIAN SPECIES No. 630, pp. 1-8 (1999)