It is not uncommon for a fire to occur when transporting hay.

Most hay fires on farms are normally caused by spontaneous combustion.

Such fires damage or destroy buildings and equipment in addition to the hay consumed.

Oddly enough, wet hay is more likely to lead to a spontaneous combustion fire than dry hay.

If hay is put into a barn or stack when it has more than about 22 percent moisture, not only does the hay lose forage quality, but also it has an increased risk of spontaneous combustion.

To avoid hay fires, small, rectangular bales should not exceed 18 to 22 percent moisture, and large round or rectangular bales should not exceed 16 to 18 percent moisture for safe storage.

Watch for the following temperatures:

--150 degrees F (65 degrees C) is the beginning of the danger zone. After this point, check temperature daily.

--160 degrees F (70 degrees C) is dangerous. Measure temperature every four hours and inspect the stack.

--At 175 degrees F (80 degrees C), call the fire department. Meanwhile, wet hay down and remove it from the barn or dismantle the stack away from buildings and other dry hay.

--At 185 degrees (85 degrees C) hot spots and pockets may be expected. Flames will likely develop when heating hay comes in contact with the air.

212 degrees (100 degrees C) is critical. Temperature rises rapidly above this point. Hay will almost certainly ignite.