Berula erecta aka Water Parsnip

Berula erecta, or lesser water parsnip, is in the Apiaceae family. This herbaceous perennial grows in wet ground and lives for years. Kew gives its native range as southern Canada to Guatemala. The RHS lists Britain and Ireland as native lands too. Plants For A Future gives a wider range. It lists Europe, Asia, and North America. Thus, these sources differ on the plant's range. It grows in ditches, canals, ponds, fens, and marshes.

The plant forms upright clumps about 3.3 feet [1 metre] tall. Grooves run down its hollow stems. Its pinnate leaves have parts set along a shared stalk. They give the clump a fine, feathery look. Crush the leaves to release a faint scent like parsley. The plant sheds its leaves; they do not stay green year-round. The RHS says it takes one to two years to mature. It gives no width for the clumps at that stage.

Small white flowers bloom from June through September. Each flower has five petals. They form groups shaped like small umbrellas. Their pale colour stands out against the split green leaves. The long bloom season spans summer and runs into early autumn. The source accounts give no facts about the fruit. Nor do they say how pollen or seeds spread.

The plant needs wet soil to grow. The RHS lists clay and loam with neutral or alkaline pH. It also lists soil that drains poorly. Its advice on light does not agree across the page. The table for site choice says full shade. The notes on how to grow it call for full sun. The RHS gives it a UK hardiness rating of H7. Plants For A Future gives USDA zones 3–7. It suits bog gardens and wet parts of informal gardens. The RHS lists wildlife gardens and bedding as uses too. Split clumps to make more plants. Remove old or dead leaves in late winter or early spring. The RHS reports few pest or disease problems.

Treat food-use records with care, given the concerns about safety. Plants For A Future records past food use of leaves and flowers. Yet it warns that the plant can kill grazing animals. Those food records do not prove it is safe to eat. The same source lists past folk uses on the body's surface. These aimed to treat rheumatism, rashes, swelling, and athlete's foot. These records show past use, not proof that treatment works.