One of the first things you need to think of before you ever start a fire is what exactly you are planning on burning. As you may know White Birch Bark and other dry hard woods are great for starting a fire. Other plants though, like the Cashew Plants or Anacardium occidentale give off toxic gases when set ablaze. There have been numerous reports of throat irritation, naseau, vomiting, unusual fatigue, blindness and even death. Never under any circumstances burn cashew plants or any type of plant from the Anacardium family which is the same family that has poison ivy and poison oak in it!
Cashew plants aren't all bad though, not only do they make a tasty treat when processed correctly, but their seeds can be ground up into a powder and used for snake bites! The nature oils in the nuts can also be used to heal cracked heels.