In the process of developing a winter hardy culinary pea for Michigan (Markarian et al., 1968), it has been determined that the habit of plant growth necessary to accomplish over wintering is a rosette of spreading branches with short internodes, lying prostrate on the ground. Inheritance of number of stem-branches in peas sown on September 7, 1964, in East Lansing, Michigan, was studied by comparing inbreds, reciprocal hybrids, and their selfs and backcrosses. Parental inbreds were Jade, an early, upright, predominantly single stemmed culinary type and a F5 selection of a hybrid between Early Perfection and Austrian Winter which had the prostrate growth habit described above. A range of segregation from 1 to 8 branches observed in F2 and F3 populations indicates two major gene pairs acting in an additive manner.