A fourth step for a hybrid cross may comprise {HEAD ~ cross pollination} between {TAIL ~ the first and second parent pea plants} 
A fourth step for a hybrid cross may comprise { HEAD ~ cross pollination } between { TAIL ~ the first and second parent pea plants }
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL