Iris species: Iris

Family

Iridaceae

Common Names

Iris, sword lily, blue or yellow flag.

Plant Description

A genus of about 300 species of upright perennials arising from a tuberous root or bulb that are native to the northern hemisphere. Leaves are basal, leathery, linear, often arranged in a fan, and are deciduous in many species. Flowers are produced in terminal clusters of one to several, and are radially symmetrical. Some species have a ridge of hairs along the center of the petals and are referred to as bearded irises. Iris species have 3 sepals and 3 petals, and come in colors of white, blue, yellow, and purple (Fig. 221, Fig. 222, Fig. 223 and Fig. 224). Numerous hybrids have been developed. Fruits are oblong, 3 - 6 angled capsules with numerous seeds arranged in rows.

Figure 221. Iris reticulata.

Figure 222. Iris pseudacorus.

Figure 223. Bearded Iris hybrid.

Figure 224. Beardless Iris.

Toxic Principle and Mechanism of Action

All parts of the plant but especially the rhizomatous roots, bulbs, and seed capsules contain pentacyclic terpenoids such as missourin, missouriensin, and zeorin [1]. These compounds are irritants and cause gastroenteritis if ingested, and contact dermatitis in some people handling and contacting the sap [2,3].

Risk Assessment

Irises are commonly grown for their striking flowers and the rhizomatous roots, which grow at the soil surface, are readily accessible to pets. Rhizomes or bulbs stored over-winter in the house are always a potential source of poisoning to household pets.

Clinical Signs

Excessive salivation, vomiting, and diarrhea follow the ingestion of iris rhizomes. Treatment when necessary may require intestinal protectants and intravenous fluids to counteract the effects of dehydration.