Penstemon cardinalis ssp. Regalis
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Worthington, R.D. (2007) Lincoln National Forest, Inventory Completion Report, Field Notes. Guadalupe Rabbitbrush Surveys: 2007. Guadalupe RD, Lincoln NF, USFS. 3 p.
Worthington, R.D. (2007) Lincoln National Forest, Inventory Completion Report, Field Notes. Guadalupe Rabbitbrush Surveys: 2007. Guadalupe RD, Lincoln NF, USFS. 3 p.