Montana Field Guide

PLANTS: Mat-forming, herbaceous, perennial forb that grows from a branched caudex. Plants are short with ascending flowering stems, 4-20 cm tall. Foliage is gray from soft-matted hairs (tomentose)

LEAVES: All basal with long petioles and some persisting dead leaves (marcescent). Blades are oblanceolate to spatulate in shape, 1-3 cm long, and greyish from the tomentose hairs on both surfaces.

INFLORESCENCE: Capitate (head-like cluster of flowers atop a stem (scape) which lacks leaves or any branching). Consists of 2-5 (7) involucres which hold the individual flowers and are subtended by 2-6 linear to lanceolate leaf-like bracts. The 5 involucral bracts are erect, tomentose, and 3-5 mm long. Flowers are 1-3 mm long. Petals and sepals are undifferentiated (tepals), white- or rose-colored, oblong in shape, fused (connate) at their lower third, and pubescent. Stamens are exserted beyond the tepals and have long-loose hairs along the filaments.

Sources: Reveal in FNA 2005; Lesica et al. 2012.

Barren, rocky, sandy or fine-textured soil of badlands, steep slopes, and ridge crests in the plains and valleys of Montana (Lesica et al. 2012).

INVERTEBRATE-PLANT INTERACTIONS
The northern population of the Mormon Metalmark (Apodemia mormo) Butterfly occurs in the prairies of Saskatchewan, Canada and along the Milk and Missouri Rivers and their tributaries in the United States, but is disjunct (geographically separate) from the main distribution in the southwestern USA (Opler 1999; Pruss et al. 2008). Throughout its range this butterfly uses several species of Eriogonum (Wick 2013). In Saskatchewan Mormon Metalmark uses the Small-flowered Buckwheat (Eriogonum pauciflorum) as an obligatory food plant (i.e., host plant) for larvae and as a primary nectar source for adults (Pruss et al. 2008). Rubber Rabbitbrush (Ericamerica nauseosa) is used as a secondary nectar source, although it is not always present where butterfly colonies occur (Wick 2013). Adult butterflies use Small-flowered Buckwheat, Rubber Rabbitbrush, and Creeping Juniper (Juniperus horizontalis) plants, bare soil, and rocks for perching and mating (Wick 2013). Ashley Wick studied why the Mormon Metalmark Butterfly does not occur in many areas of Saskatchewan where the host plant, Small-flowered Buckwheat, is abundant (2013). Wick found that the female butterflies in the prairie population oviposit in small crevices in the soil and on rocks near Small-flowered Buckwheat, but not directly on the host plant as previously thought from studies of other populations (Wick et al. 2012). Thus, micro-habitat characteristics in addition to Small-flowered Buckwheat abundance interact to affect the butterfly’s distribution. Her study provided the first documentation of the oviposition of the Mormon Metalmark Butterfly in Canada and showed that this behavior diverges from that seen in other parts of the butterfly’s range (Wick 2013).

POLLINATORS
The following animal species have been reported as pollinators of this plant species or its genus where their geographic ranges overlap: Bombus bifarius, Bombus centralis, Bombus flavifrons, Bombus huntii, Bombus melanopygus, Bombus mixtus, Bombus ternarius, Bombus occidentalis, Bombus insularis, and Bombus flavidus (Thorp et al. 1983, Koch et al. 2012, Williams et al. 2014).

A recovery strategy was developed for the Mormon Metalmark Butterfly's Prairie Population in Canada (Pruss et al. 2008). This recovery strategy provides background information, recovery goals, and recommended approaches to promoting the recovery of the butterfly, its habitat requirements, and conservation efforts for other species that are part of its habitat, such as the Small-flowered Buckwheat (Eriogonum pauciflorum).