Sidalcea oregana (Nutt. ex T. & G.) Gray 

 Oregon checker-mallow 



A. DESCRIPTION 



1. General description: This is a large, showy, herbaceous 

 perennial in the Malvaceae (mallow family) . The leaves 

 usually vary on the same plant from nearly round and shallowly 

 lobed at the base to deeply palmately lobed or compound on the 

 tall flowering stems. The flowers are borne in showy racemes 

 and have five sepals, five pink-purplish petals, and many 

 stamens whose filaments form a tube around the pistil. The 

 fruit is composed of segments which separate and are arranged 

 around an axis, somewhat like a cut pie or round of cheese. 

 See slides 8 and 9 in Appendix D. 



2. Technical species description (quoted from Hitchcock and 

 Cronquist 1961) : 



Perennial from a stout taproot and branched crown, but 

 without rootstocks; stems 2-15 dm tall, from glabrous to 

 hirsute or stellate below, finely stellate above; racemes 

 simple to compound, from closely many-flowered and 

 spikelike to open and lax, the pedicels 1-10 mm long; 

 calyx 3.5-9 mm long, from uniformly finely stellate to 

 bristly with a mixture of longer, simple to 4-rayed, 

 spreading hairs sometimes as much as 2.5 mm long; petals 

 1-2 cm long, light pinkish to fairly deep watermelon 

 pink; carpel 2.5-3 mm long, from nearly smooth to 

 reticulate-alveolate on the sides and back; beak 0.3-0.7 

 mm long. 



3. Diagnostic characters (adapted from Hitchcock and Cronquist 

 1973): stigmatic surfaces along the lengths of the style 

 branches, not capitate; filaments connate in groups of 2-6; 

 leaves dimorphic, nearly orbicular shaped to deeply palmately 

 lobed but not shaped like maple or grape leaves. The leaf 

 shape can be used to easily distinguish this species (even 

 vegetatively) from Iliamna rivularis , a member of the 

 Malvaceae which is common along Hyalite Creek. 



B. GEOGRAPHIC DISTRIBUTION 



1. Species range: from central Washington to California, east 

 to Wyoming and Utah (Hitchcock and Cronquist 1973) and 

 Montana . 



2. Montana distribution: known only from Hyalite Canyon in 

 Gallatin County and the Mission Valley in Lake County. 



3. Occurrences on the Gallatin National Forest: I found two 

 subpopulations in Hyalite Canyon, one just above Hyalite 

 Reservoir, the other slightly further upstream in the meadow 

 below Window Rock Forest Station. Prior to this project, the 



25 



