I don't have to look up my family tree, because I know that I'm the sap.
It is daffodil time, so the robins all cry, For the sun's a big daffodil up in the sky, And when down the midnight the owl calls "to-whoo"! Why, then the round moon is a daffodil too; Now sheer to the bough-tops the sap starts to climb, So, merry my masters, it's daffodil time.
The larch ... is not only preserved from decay and the worm by the great bitterness of its sap, but also it cannot be kindled with fire nor ignite of itself, unless like stone in a limekiln it is burned with other wood. ...This is because there is a very small proportion of the elements of fire and air in its composition, which is a dense and solid mass of moisture and the earthy, so that it has no open pores through which fire can find its way... Further, its weight will not let it float in water.vitruvius