I'd never heard of these before: http://nyis.info/invasive_species/water-chestnut/ http://nyis.info/invasive_species/water-chestnut/ The other common name ("wa

I'd never heard of these before: http://nyis.info/invasive_species/water-chestnut/ http://nyis.info/invasive_species/water-chestnut/ The other common name ("water caltrop") is illuminating.