318 Annual Report Agricultural Experiment Station . 



showed 92 percent of all plants having zero length of the first inter- 

 node, 66 percent having zero length of the first and second, and 1 

 percent having zero length of the first, second and third internodes. 

 This leaves 8 percent having two primary leaves. Then 92 percent 

 of 66 percent, or 61 percent, of all plants should have had four or 

 more, thus leaving 92 less 61, or 31 percent, of all plants with three 

 primaries. Also 1 percent of 61 percent, or 0.6 percent, of all plants 

 should have had five primary leaves, leaving about 60 percent with 

 four primaries. Table VII shows how nearly the actual count in 

 one race approaches the theoretically expected. 



TABLE VII. — NUMBER PRIMARY LEAVES 



A number of pure races of teparies were planted in the screen 

 garden on the campus during the last spring and summer wdth the 

 plan in view to obtain a number of reciprocal crosses in order that a 

 new set of hybrids might be produced. Considerable efforts were 

 expended in developing a practical and effective method of open 

 field cross pollination of beans. 



An interesting segregation appeared this year coming from 

 the Fi seed of a cross between a taine and a wild tepary. A further 

 investigation wnll be made with the various segregates. 



ALFALFA 



The work with alfalfa has been with three series of plots. One 

 of these plots is located in the screen garden on the campus, and 

 the other two are on the Salt River Valley Farm, 



The plot in the screen garden consists of 342 transplanted plants 

 from various sources. Most of these plants were taken from the 

 best plots of the Evergreen Nursery when the work at that place 

 was discontinued in 1916. About twenty-five of these plants were 

 taken from the Hairy Peruvian alfalfa which w-as growing on the 

 north side of the Salt River Valley Farm in the fall of 1917. An 

 individual plant study has been made of (1) heat resistance, as indi- 

 cated by rapidity of growth and yield of consecutive cuttings as the 

 heat of the summer comes on, and (2) quality, as indicated by size 

 of stems and percentage of leaves. The work was confined mostly 

 to the study of heat resistance. The entire plot was irrigated about 



