The combustion of cellulosic material and of related starch, starch components is followed using a simultaneous TG-DTA unit. The materials were characterized using solid-state NMR. It was found that the combustion proceeded via gaseous combustion. A study of the degradation in nitrogen on the thermal analysis equipment shows that the glowing combustion originated from carbonaceous residues of the degradation of the material during the gaseous combustion step. The alpha(r)-alpha(s) method of following the degradation in nitrogen was used to show the reactivity pattern on a comparative basis. This method was also used to study the reactivity pattern in the overlapping combustion reaction in air. In both the cases, the cationic material appeared to have higher reactivity than the unmodified native material.