Halkaas waxay ka qaataan wadooyin kala duwan - dhanka harooyinka waaweyn, waqooyi bari iyada oo loo marayo dooxada St. Lawrence ilaa Quebec, ama xeebta bari ee sare.
Dabcan, nooc ka sii adag ee jumlada ayaa ah "Meeshaas, waxay inta badan qaataan dhowr waddo - dhanka Great Lakes, waqooyi-bari iyada oo loo marayo Dooxada St. Lawrence ee Quebec, ka baxsan Xeebta Bari ee sare, ama iyada oo loo marayo Rocky Mountains ee gobolka Oklahoma / Texas, ka dibna waqooyi-bari dhanka Great Lakes. "