It is difficult to burn a heap of green leaves but not a heap of dry leaves. Explain why?

For any substance to burn, it must reach its ignition temperature first. Ignition temperature is the lowest temperature at which a material catches fire. Green leaves contain water/moisture due to which their ignition temperature becomes high (i.e. the temperature at which they will catch fire becomes very high) as compared to that of dry leaves which do not contain water content. So it is difficult to burn green leaves due to their high ignition temperature. On the other hand dry leaves easily reach their ignition temperature even on receiving small amount of heat, so they burn easily.