Microcrystalline silicon with various crystalline volume fractions was prepared by plasma enhanced chemical vapour deposition. The material was studied by steady state and transient electron spin resonance in the dark and under light illumination. The observed resonances at g-values of 2.01, 2.0052, 2.0043, 1.998 can be attributed to the amorphous and microcrystalline constituents, and their respective intensities change as the ratio of amorphous to crystalline volume is varied. The origin of a fifth resonance at g = 1.995 remains unclear. Smaller crystalline volume fractions lead to lower spin densities and affect the recombination behaviour of photogenerated charge carriers. The recombination behaviour in highly crystalline material is also influenced by moderate Fermi level shifts, where differences show up between n-type (or undoped) and p-type samples. The differences are attributed to trapping of photo-generated holes in deep states within the disordered regions.