In order to carry out the provisions of this chapter, the uses of buildings or other structures and of land are hereby classified and combined into use groups listed below. A lower number of a use group indicates a more restricted use group.
A. 
Use Group 1: uses first permitted in the R-1 District.
B. 
Use Group 2: uses first permitted in the R-2 District.
C. 
Use Group 3: uses first permitted in the R-3 District.
D. 
Use Group 4: uses first permitted in the R-4 District.
E. 
Use Group 5: uses first permitted in the R-A District.
F. 
Use Group 6: uses first permitted in the R-C District.
G. 
Use Group 7: uses first permitted in the C-1 District.
H. 
Use Group 8: uses first permitted in the C-2 District.
I. 
Use Group 9: uses first permitted in the M-1 District.
J. 
Use Group 10: uses first permitted in the M-2 District.
Unless otherwise provided:
A. 
When a use is first included in any use group, such use shall be interpreted as being excluded from any use group with a lower number.
B. 
A use which is not listed in any zoning district shall be interpreted as being excluded from all use groups until this chapter has been amended listing such use as a permitted use in the appropriate district.