STUDIES ON BEAN BREEDING. 165 



breeding seed again. But new crossing will take place every 

 year and consequently in spite of rigid selection the beans 

 become more and more mixed each year. To our knowledge 

 the bumble-bees have in this way put more than one large 

 grower out of business. 



The first thing that the bean grower must realize is that his 

 seed must be produced in an isolated field where there is little 

 opportunity for crossing with other varieties. In Circular No. 

 (510-5-15) of this Station we have attempted to give some direc- 

 tions which will aid the grower in producing and maintaining 

 pure breeding strains. But in order to do this successfully the 

 grower must limit himself to one, or at the most two varieties. 

 Each of these must be grown in fields separated not only from 

 his own but from his neighbors' beans. 



There seems to be no reason why the bean crop should not 

 become a very important one in Maine. Most of the varieties 

 of bush beans will easily mature in from 90 to 100 days. For 

 the southern and central parts of the State it is a practically 

 sure crop so far as frost is concerned. The return per acre 

 compares very favorably with that of the cereals. Further the 

 bean plant is a legume, belonging to the same general family 

 to which the clover belong. The great benefit brought to 

 soils by cropping with clovers lies in the ability of these plants 

 to gather nitrogen from the air through the agency of the 

 bacteria living in the nodules on the roots. The bean plant also 

 collects nitrogen from the air by similar means. Thus at the 

 same time that a profitable crop is being produced, the soil is 

 being enriched by the addition of nitrogen. For a large por- 

 tion of the State beans are an excellent crop to use in the rota- 

 tion. 



Yellow Eye Beans. 



The most popular varieties of beans grown in the State are 

 the so-called Yellow Eye. Of these there are two principal 

 classes, the Improved Yellow Eye and the so-called Old Fash- 

 ioned Yellow Eye. Conversations with growers within the 

 State have revealed the fact that there is a great difference 

 of opinion as to the distinction between these two types of 

 beans. Some growers are inclined to make the distinction upon 

 the shape of the bean without reference to the color pattern, 



