About Ludwigia grandiflora (Michx.) Greuter & Burdet
Ludwigia grandiflora, commonly called water primrose, is an aquatic plant belonging to the order Myrtales. It is closely related to Ludwigia hexapetala, and the two species are easily confused with one another. They can be distinguished at the chromosomal level: L. grandiflora is hexaploid, while L. hexapetala is decaploid. They can also be told apart by morphological characteristics. L. grandiflora has villous hairs, smaller flowers, and smaller pollen grains. Some botanical authorities consider these differences too small to recognize the two as separate species, and instead classify these taxa as two different varieties or two different subspecies.
