BIRDSFOOT TREFOIL AND BIG TREFOIL 11 



States who have used it for pasturage, and it is one of the qualities 

 that adds greatly to its value. 



ENEMIES 



Several of the common insect pests of clover and alfalfa have been 

 reported to occur on birdsfoot trefoil in Europe and Russia, although 

 no serious injury by them has been mentioned. These insects also 

 occur in the United States, but the only material injury by them 

 reported in this country was a case reported by Monteith and Hollo- 

 well (5) in which nursery rows "were heavily infested with the potato 

 leafhopper" and showed injury similar to that caused on alfalfa 

 by this insect. 



DESCRIPTION OF VARIETIES AND FORMS 



A number of varieties and forms have been described under both 

 Lotus uliginosus and L. corniculatus . L. corniculatus in particular is 

 extremely variable and, even from seed used for commerical plantings, 

 plants that differ widely are usually present. Under natural con- 

 ditions regional strains have developed, and these constitute the 

 many variants that have been given varietal and form designation. 

 For the most part shape of leaflets and habit and size of the plants 

 have been the basis of differentiation, but in some cases color and 

 number of flowers have been recognized. The following descriptions 

 and keys give the specific characters that separate species, varieties, 

 and forms and indicate the range of variation that exists. 



The characteristics that distinguish L. corniculatus and L. uliginosus 

 from all other Lotus species are as follows: 



Styles not dentate; flowers yellow; calyx campanulate; teeth equal and equaling 

 the tube; leaves not dotted or revolute; banner equaling the wings and keel; 

 bracts three; stem of keel shorter than the keel. 



The only characteristics definitely distinguishing the two species 

 are the rhizomes and flowers. The definite features of these are as 

 follows: 



Flowers usually 8 to 12 (rarely 6 to 7); rhizomes spreading. 



L. uliginosus Schkuhr. 

 Flowers 5, sometimes 6, and rarely 7; rhizomes not spreading. 



L. corniculatus L. 



L. uliginosus is only moderately variable and but two varieties 

 have been described. The following key gives the characteristics 

 separating these: 



Plants smooth or nearly so var. glabriuscul us Bab. 



Plants hairy var. villosus (Thuill.) Lamol fee. 



L. corniculatus is extremely variable, and a large number of varieties 

 have been described. Many of these were originally given specific 

 rank. The following key indicates the wide range of variation and 

 gives the principal characteristics distinguishing the different variel ies 

 and forms. 



