To collect Birch sap
Access to a stand of Birch trees
A drill and plastic pipe or Knife and peg.
Choose a time when the sap is starting to rise up the trees between early mach and in this years case (2013) Mid April
Drill a small hole the size of the plastic pipe at an upwards 30 degree angle about 5 mm deep into the bark. Withdraw the drill and see if the sap starts to run. If not a little deeper. When the sap runs put the pipe in and let it collect in a plastic bottle.
When you have enough ( I can let you know later how fast it runs) remove the pipe and seal the hole with either mud or a wooden plug.
There are plenty of help on various bushcraft web sites.
I plan to 1 make some Birch syrup though it takes a lot of sap. 2 Maybe for personal consumption make some wine.