[R] Degrees of Freedom Not Allocated to Residuals in Reduced Model

##I am trying to test for fixed factor main effects in an unbalanced mixed effects model but when I fit the reduced model for mic factor effects, the extra degrees of freedom are being allocated to a nested term rather than the residuals. The model has inc, mic and spp are independent

[R] Degrees of Freedom Not Allocated to Residuals in Reduced Model

I am trying to test for fixed factor main effects in an unbalanced mixed effects model but when I fit the reduced model for mic factor effects, the extra degrees of freedom are being allocated to a nested term rather than the residuals. The model has inc, mic and spp are independent