Water caltrop
Trapa natans
Horned aquatic fruit, also called water chestnut in some languages. Invasive in some U.S. waters. Cooked seed is a food in some cuisines. Do not dump in lakes.

GROW → HARVEST → EAT → DRY → POWDER → CAPSULE → GUMMY — forms are not equivalent. Food first.
Identity
What it is
Horned aquatic fruit, also called water chestnut in some languages. Invasive in some U.S. waters. Cooked seed is a food in some cuisines. Do not dump in lakes.
Edible portions
- cooked seed where it is a known food
Absence of a portion from this list means it is not treated as food here — not that every other part is toxic.
Growing
- Climate. Aquatic; invasive in parts of the U.S.
- Light. Full sun water
- Soil. n/a — floating aquatic
- Planting. Do not introduce into U.S. waterways.
- Harvest. Where it is a traditional crop, not from a banned pond.
Preparation and culinary uses
- Boiled seed in cuisines that use Trapa
Safety
- Invasive status matters more than your recipe. Don’t spread it.
Next steps
Sources
- USDA PLANTS Database — taxonomy and range (verify current entries)
- No USDA FoodData Central nutrient profile is attached here. That is not a claim that the plant contains no nutrients.
- State cooperative extension growing guides — verify for your region
Honest incompleteness is preferred to fabricated completeness. If a section is missing, no record for it is attached here — not a claim that the plant lacks that characteristic, and not that it was omitted as a secret.
Internal quality class A. Strong page: distinctive plant facts plus practical growing or kitchen use.