"Value" is in the eye of the beholder. For me, value is multi-dimensional and includes amount and quality of food produced, ease of harvest, resistance to diseases, insects, bird and mammal predation. I also like long windows for harvest and the ability to store the food in its raw form with little energy burden.
If a species does not produce food for man or beast it can still be of high value if it produces high-quality timber or rot-resistant woods. If it doesn't produce food or timber then it can still provide fuel.
Some ecosystems are niches that are difficult to fill.
Some types of bottomlands are inhospitable for many food-producing crops.
For example, one standard for the application of "riparian law" in Michigan is "land that has never had a successful crop of corn taken off of it."
Other types of bottomland are extremely favorable for corn and soybeans. For example, organic soils that are developed with artificial drainage and high-flats.
Zooming into the preferred species for the very wettest regions of a flood plain, the mast producers are Overcup Oak, Water Hickory and Persimmon. Among the timber producers, Baldcypress is the clear winner.
Source of information: Bottomland Hardwood Management from Mississippi State University