tinder-dry
From Longman Dictionary of Contemporary Englishtinder-dryˈtinder-dry adjective DRYextremely dry and likely to burn very easily The whole forest is tinder-dry.Examples from the Corpustinder-dry• He then threw them on to the ground in the tinder-dry hay loft without putting them out properly, it is alleged.• His prey is the charred remnants of a campfire set along a trail in the heart of this tinder-dry wilderness area.