About Tolmiea menziesii (Pursh) Torr. & A.Gray
Tolmiea menziesii has hairy, toothed leaves with five to seven lobes, and produces capsule fruit that contains spiny seeds. It produces many small flowers arranged in a loose raceme. Each individual flower has a tubular purple-green to brown-green calyx, and four linear or awl-shaped (subulate) red-brown petals that are roughly twice as long as the sepals. This species has unusual reproductive strategies: it grows new plantlets from the petiole near the base of every leaf. These plantlets detach, fall onto soil, and take root to grow new individuals. It can also reproduce via rhizomes and via seeds. When its leaves are crushed, they release a strong odour that resembles cucumber. The compound (2E,6Z)-2,6-nonadienal has been identified as the source of this odour. In its natural environment, the banana slug Ariolimax columbianus is a selective feeder, and has not been observed feeding on this plant. In controlled feeding experiments, banana slugs rejected lettuce leaves that had been treated with (2E,6Z)-2,6-nonadienal. Tolmiea menziesii is commonly cultivated as an ornamental plant. It is used as a houseplant, or planted as a groundcover in gardens. It requires moist conditions and cannot tolerate much direct sun or dry environments.
