There is a different code for each type of farm - soy, goats, wheat, etc... You can look up your specific type of farm on the NAICS website here: https://www23.statcan.gc.ca/imdb/p3VD.pl?Function=getVD&TVD=1369825

To obtain your industry code based on your particular work, follow this link, and you can look up your designated industry code. 

Choose Agriculture, then continue by choosing what type of farming you do until you get to the 6-digit number needed.

Visit - 6-DIGIT NAICS CODE REFERENCE LIST