E. and Central U.S., S. Canada
Cedar waxwings (Bombycilla cedrorum) eat the pomes; seeds are not crushed or digested in passage through their gut... Hawthorn fruits do not provide complete nutritional needs for cedar waxwings. Hawthorn fruits appear to be eaten primarily as a readily available caloric and nitrogen source at a cost of extremely negative budgets for water and some common minerals. Ingestion of progressively more fruits places cedar waxwings in progressively more positive energy and nitrogen balance while simultaneously placing the birds in progressively greater water and mineral deficits." 
"Crataegus phaenopyrum is an important woody ornamental valued for its tree-like habit, glossy, ivy-shaped leaves, fine fall color, and brilliant, persistent vermilion berries." 
Dessication of bare-root nursery stock during storage and after transplanting is a leading cause of post-transplant tree death. A study of Washington Hawthorn found that the length of cold storage is inversely correlated with stem xylem water potential, and that dipping the entire shoot system in paraffin wax greatly ameliorated post-transplant water stress during storage. 
 Studier, E. H., Szuch, E. J., Tompkins, T. M., & Cope, V. W. (1988). Nutritional budgets in free flying birds: cedar waxwings (Bombycilla cedrorum) feeding on Washington hawthorn fruit (Crataegus phaenopyrum).
 Bates, R. M. (1994). Characterization of water stress during cold storage and establishment for Acer platanoides and Crataegus phaenopyrum (Doctoral dissertation, Virginia Tech).
 Phipps, J. B. (1998). Synopsis of Crataegus Series Apiifoliae, Cordatae, Microcarpae, and Brevispinae (Rosaceae Subfam Maloideae). Annals of the Missouri Botanical Garden, 475-491.