A biology research paper, written in 1934, and published in the Journal of Mammalogy in 1936, discusses the diets and habitats of the Florida Marsh Rabbit. Unfortunately the paper is not available for public viewing, but I would like to share with you the information gleaned from the rabbits.
About 9 rabbits were captured from Newnan's Lake area, east of Gainesville, Florida, and fed plants found in the surrounding habitat. Sixty-four different species of plants were offered. Some were eaten right away, others eaten only when hungry, and others were not even on pain of starvation (yes, bunnies died during this experiment).
Trees and Vines Eaten Readily
French Mulberry (Callicarpa americana)
Dwarf thorn (Craiaegus uniflora)
Blackberry (Rubus betulifolius)
Dewberry (Rubus continentalis)
Sweet gum (Liquidambar styraciflua)
Common elder (Sambucus canadensis)
Red bud (Cercis canadensis)
Ward's willow (Salix longipes)
Yellow jessamine (Gelsemium sempivirens)
Water oak (Quercus nigra)
Groundsel tree (Baccharis halimifolia)
Saw brier, Green brier, wild bamboo, jackson brier, sarsparilla (Smilax spp.)
Herbs and Small Plants Eaten Readily
Centella (Centella repanda)
Marsh pennywort (Hydrocotyle spp.)
Cattail (Typha latifolia)
Rush (Juncus effusus)
Arrowhead (Sagittaria lancifolia)
Smartweed (Persicaria hirsula)
Ground cherry (Physalis floridana)
Nightshade (Solanum sisymbriifolium)
Water hyacinth (Piaropus crassipes)
Ruellia (Ruellia parviflora)
Golden club (Orontium aquaticus)
Violet (Viola esculenta)
Yellow woodsorrel (Xanthoxalis langloisii)
Sow thistle (Sonchus oleraceus)
Golden fumeroot (Capnoides aereum)
Cinnamon fern (Osmunda cinnamomea)
Bracken (Pteridium aquilinum)
Chain fern (Woodwardia arealata)
Eaten when no other food was available : Saw palmetto, Lizard's tail, Hackberry, Cabbage palm, Water starwort, mushroom
Absolutely refused : Papaw, Wild plum, Poison ivy, Persimmon, Magnolia (grandiflora), Holly, Muscadine grape, Red mulberry, Wax myrtle, Gallberry, Deer tongue, Spanish Moss, Bonnets, Pokeweed