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Abstract
The third measurement of Iowa?s forests was completed in 1990 by the North Central Forest Experiment Station and the Iowa Department of Natural Resources (Brand and Walkowiak 1991). The inventory found that black walnut trees are common in the forests of Iowa. Two out of every hundred trees in the State are black walnuts. To accomplish the inventory, more than 12,769 potential sample points were examined on aerial photos. Of these, 632 forest plots were visited and measured. Although most of Iowa is farmland, 2.05 million forest acres covered 5.7 percent of the State. Field crews found walnut on 27 percent (192) of the plots they measured.
Citation
Vasievich, J. Michael; Kingsley, Neal P. 1996. Where are the Black Walnut Tres in Iowa? 1996. Walnut Council Bulletin. 23(1): 6-10. [Zionsville, IN]