Correct Cuts and Sap Flow
Not to be confused with the disease of wood called "wetwood". When pruning is done in late winter, sap may flow from the wound. This will contain some carbohydrates. This is a defense feature. Its a good thing. Squirrels and sap suckers seem to be well aware of this defense feature. Some people claim the tree is "bleeding". I wonder if they put blood on their pancakes?
More information on "Sapsuckers".
Here the sap has begun to flow on this Japanese Maple. The final correct cut would be along the red line.