This is the "foo" tree (rhymes with screw) and is especially serious if the sap gets in your eyes. It has the unusual property that until it comes in direct contact with water it's only an irritant but as soon as one tries to wash it away it blinds the hunter immediately and can even cause death. The sap sadly has a horrible odor (like shit) and it is from this tree and it's unusual nature that the saying developed....."if the foo shits, wear it!