Probable Base Number for Genus x = n=10
E. fistulosum n=10 ref Grant 1953; Lamont 1995; Watanabe et al. 1990 (listed as Eupatorium fistulosum)
E. maculatum n=10 ref Grant 1953; King et al. 1976; Lamont 1995; Watanabe et al. 1990 (listed as Eupatorium maculatum)
E. purpureum n=10 ref Grant 1953; King et al. 1976; Lamont 1995; Watanabe et al. 1990 (listed as Eupatorium purpureum)
E. steelei n=10 ref Lamont 1995 (listed as Eupatorium steelei)
References
Grant, W. F. 1953. A cytotaxonomic study in the genus Eupatorium. American Journal of Botany 40: 729-742.
King, R. M., D. W. Kyhos, A. M. Powell, P. H. Raven, and H. Robinson. 1976. Chromosome numbers in Compositae. XIII. Eupatorieae.
Annals of the Missouri Botanical Garden 63: 862-888.
Lamont, E. E. 1995. Taxonomy of Eupatorium section Verticillata (Asteraceae). Memoirs of the
New York Botanical Garden 72: 1-66.
Watanabe, K., M. Ito, T. Yahara, V. I. Sullivan, T. Kawahara, and D. J. Crawford. 1990. Numerical
analyses of karyotype diversity in the genus Eupatorium (Compositae, Eupatorieae). Plant
Systematics and Evolution 170: 215-228.