(Sarg. ex C.K.Schneid.) Rehder
Mayhaw is the name given to the fruit of the species of Crataegus series Aestivales that are common in wetlands throughout the southern United States. The principal species are C. aestivalis, the eastern mayhaw, and C. opaca, the western mayhaw.
Mayhaws grow in moist soil in river and creek bottoms under hardwood trees. The fruit ripens in late April through May, thus the name mayhaw. The fruit is also found in bayous surrounding lakes, such as Caddo Lake on the Texas/Louisiana border. Mayhaws are often collected out of the water from boats, and the fruit is used to make jelly.
Families used to go on outings to collect mayhaws and create stockpiles of the jelly to last throughout the year, but the tradition has declined with the increasing urbanization of the South and the destruction of the mayhaw's native habitat. The fruit has also been cultivated to grow outside of wetlands, and this is increasing the source of the jelly.
In culture 
Many communities associate themselves with the fruit because of its reputation as a celebrated delicacy of Southern U.S. cuisine. For example, Colquitt, Georgia holds a mayhaw festival in April. Daisetta, Texas; El Dorado, Arkansas; Marion, Louisiana and Starks, Louisiana all celebrate a mayhaw festival each May.
"May-Haw" is also the name of a local variety show in Colquitt, Georgia that was developed by local theater group Swamp Gravy. The show is performed twice a year, in April and January; the April performance coincides with the mayhaw festival.
- Phipps, J.B.; O’Kennon, R.J.; Lance, R.W. 2003. Hawthorns and medlars. Royal Horticultural Society, Cambridge, U.K.