Meadow Deathcamas

Toxicoscordion venenosum is a bulb plant 20–70 centimetres (8–27+1⁄2 in) tall when flowering in the spring or early summer. The underground bulbs are egg-shaped (ovoid) and tunicate, made up of multiple layers protected by dried outer layers like an onion. The plant's leaves appear very early in the spring and are narrow. Most of the leaves are basal, springing directly from the ground, though a few much smaller ones may attach to the flowering stem. The length of the leaf blade is 12–50 cm (4+1⁄2–19+1⁄2 in) long while only being 2–10 millimetres (1⁄8–3⁄8 in) wide. The leaves are sharply folded into a "V" shape along their length, quite unlike the leaves of wild onions, with a keel, a ridge at the bottom of the fold.

Flowering. The inflorescence usually does not have branches and is a raceme, but will sometimes have one or two branches near the base and be a panicle. If a plant does have branches, they will be one tenth to one third the length of the stem. It may be as much as 20 cm (8 in) long, or as short as 2 cm (3⁄4 in). There may be ten to fifty flowers on the flowering stem. The top of the flowering stem will be pyramidal in shape when blooming begins with smaller buds and immature flowers towards the top and open flowers towards the base. The flowers are off-white and resemble six pointed stars. …

Meadow death camas is found through much of western North America. In Canada it is found in three western provinces: Alberta, British Columbia, and Saskatchewan. In the United States, it grows from the West Coast to the Rocky Mountains (with the exception of Arizona). This includes California, Colorado, Idaho, Montana, Nebraska, Nevada, New Mexico, North Dakota, Oregon, South Dakota, Utah, Washington, and Wyoming. It also grows in the Mexican state of Baja California. The meadow death camas grows in more open, sunny habitats. The variety venenosum grows in grasslands and open pine woodlands of the interior from 500 to 1,300 metres (1,600 to 4,300 ft). The variety gramineum grows in well drained grasslands and coastal areas from sea level to as much as 2,500 m (8,200 ft). They prefer wet areas, but can grow in much drier habitats than common camas (Camassia quamash) such as on hillsides in the Sierra Nevada. They may also be found in opening in coniferous forests and among the sagebrush of the interior.

The nectar is also poisonous; controlled experiments have shown that honeybees can be fatally poisoned by the flowers, and it or its relative are suspected in a few cases of honeybee poisonings. The plant is visited by a specialist miner bee, the death camas miner bee (Andrena astragali), which is likely the only bee that can tolerate its toxins. In turn the bee is an oligolege, a species that specializes in the pollen of only a few species of flower. The death camas miner bee specializes in meadow death camas and the closely related Toxicoscordion paniculatum. Seed production for the plant is also significantly increased by bees visiting the flowers. Theories as to what advantages specialization and toleration of the toxicity of the nectar and pollen provide include that the lack of competitors for the food resources provided by the flowers and that, as with the monarch butterfly, ingesting toxic food protects the bees from predators and parasites by making them toxic. Though the death camas bee is the only bee that feeds upon death camas flowers, a fly species, Earomyia melnickae, was described in 2022 which was discovered feeding on the meadow death camas flowers. As of 2024 it is unknown where or what the species may feed upon as a larva. Extensive searches were made on the bulbs in the area where the flies were discovered, but no signs of feeding or larvae were discovered. …

Though well aware of the poisonous nature of the plants, the indigenous Paiute people have made use of crushed bulbs as poultices for a range of ailments in an identical manner to Toxicoscordion paniculatum, which they called by the same name. It was used for burns, rattlesnake bites, rheumatism, and swellings. The naturalist Ira Noel Gabrielson dismissed the species and all of its relatives (except for Toxicoscordion fremontii) as a cultivated plant due to lacking "charm enough to take up room in a garden when so many more beautiful things are available". Despite this, the species is occasionally grown in wildflower meadows or perennial borders for its spring flowers in either full sun or partial shade. Due to the toxic nature of it and all its relatives, caution is urged to avoid planting it where herbivores would have access. In the Manual of Bulbs from the Royal Horticultural Society it is listed as tolerating winter temperatures at least as cold as −15 °C (5 °F). It is hardy in USDA zones 3b–9b.