Two species, and hybrids between them, are frequently cultivated in Michigan. A specimen of Chaenomeles japonica (Thunb.) Spach was collected in 1891 by O. A. Farwell, "near Ypsilanti" (Washtenaw Co.), but without indication of whether escaped or cultivated. It has young twigs hairy, becoming warty after the hairs are shed. Chaenomeles speciosa has the young twigs glabrous, never becoming warty.
All species found in Chaenomeles
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. October 23, 2017. http://michiganflora.net/genus.aspx?id=Chaenomeles.