14 



coloration, the Colorado and Montana 

 populations are similar. 



Additional morphological comparisons were 

 summarized by Marriott (1990). The overall 

 appearance of the Wyoming plants ( A. 

 shultziorum ) is more open and loose than the 

 Montana and Colorado plants (currently 

 recognized as A_^ molybdenus ) , which are more 

 compact and low-growing in habit. In the 

 Wyoming plants, the flowers are consistently 

 cream-colored, with pale purple striations on 

 the banner, and a purple spot on the tip of 

 the keel. The Colorado plants have petals 

 that are creamy at the base and blue-purple 

 at the tips. In Montana, the flowers are 

 more extensively blue-purple. Fruit 

 morphology among the states includes the most 

 distinctive differences among the three 

 regional units. Fruits from Colorado are the 

 smallest, are shorter in relation to width, 

 and have short beaks that contract abruptly 

 from the main body of the legume. In 

 Montana, the fruits are larger, longer 

 relative to width, arcuate in shape, and 

 taper gradually into a longer beak. Fruits 

 from Wyoming appear to be intermediate in 

 morphology. They are intermediate in size, 

 but approach Montana material in relation of 

 length to v/idth. Beaks are similar to 

 Montana material, but the legumes are little 

 if at all arcuate. 



Rupert Barneby, New ^ork Botanical Garden, 

 also examined specimens from all three 

 states. In a letter to J.S. Shelly (10 

 January 1990), he stated that "(t)o my eye 

 the material all looks increasingly alike, 

 and I would now think that only one specific 

 taxon is recognizable, possibly divided into 

 varieties . " 



cpDNA ANALYSIS: Chloroplast DNA is a 

 circular strand of DNA contained in the 

 chloroplasts (photosynthetic organelles) of 

 plant cells. These circular molecules can be 

 isolated from the cells, and differences in 

 their genetic sequences can be studied by 

 fragmenting them with restriction enzymes; 

 these enzymes break the strands when they 

 "find" certain DNA base pair sequences. The 

 resulting fragments are then examined 



