27 



2. Reproductive biology: Reproduction is by seed. The 



flowering period is in July. All plants seen at the Rocky 

 Hills site were mature reproductive adults; the plants are 

 probably relatively long-lived. Many inflorescences were 

 infected with a fungus, but its effect on reproduction is 

 not known. 



F. Management considerations: 



In the study area, Sphaeromeria argentea seems to be confined to 

 a particular rock type (limestone). The large population here 

 was in near pristine habitat; future disturbance by cattle is not 

 likely either, due to the steep, rocky ground and prostrate 

 growth habit of the plants. The site near Bannack is likewise in 

 well protected and pristine habitat. However, at the bottomland 

 site where the species grows in the upper Big Sheep Creek 

 drainage, the site is impacted by cattle. Chicken sage is rare 

 and peripheral, with a very limited distribution in Montana, and 

 its abundance elsewhere is poorly known at this time. Four of 

 the five Montana occurrences are on BLM land. As a proactive 

 step to insure that this species is considered in future 

 management decisions, designation of Watch status by the BLM in 

 Montana is appropriate. Populations could potentially be 

 impacted by mining, which has often been centered in areas with 

 outcrops of limestone. Preservation of the Rocky Hills site is 

 also important because another plant species of special concern, 

 an undescribed Lesquerella (also treated in detail in this 

 report), also occurs there. 



Sphaeromeria capitata Nuttall 

 Rock-Tansy 



A. Description 



General description: This is similar to Sphaeromeria 

 argentea (see previous synopsis). The deeply lobed leaves 

 are mostly at the woody base of the plant and form dense 

 cushions over rocks. The inflorescence is a tight, 

 spherical cluster of heads of yellow, tubular flowers which 

 lack pappuses. 



Technical description: (quoted from Welsh et al . 1987) 

 Pulvinate-caespitose herbs, herbage canescent with 

 malpighian hairs; stems subscapose, 2-12(20) cm tall; leaves 

 mainly basal, 4-10 mm long. 1- or 2-palmately lobed, the 

 cauline entire and reduced upward; heads few to numerous in 

 a compact head-like cluster; involucres 3-5 mm high, the 

 broad bracts with hyaline margins; corolla 2.5-3 mm long. 



