Heat and humidity play an important role in the spontaneous combustion of organic materials. In hay, it is less likely to ignite before 10 days following harvest and satcking, however it is not unusual for this to occur in about five days where high temperatures and high humidity levels are recorded. As a general rule though, it usually takes about six weeks or longer for the organisms to reaally fester!

Don't forget that the "clinker" is a tell-tale sign of spontaneous combustion and will usually be found inside the stack.

Glad I grew up in the country as well as having the experiences in major cities.

Howard Myers