I thought I’d share this clip I filmed about a month ago, a birch tree I was pruning East of Seattle. Notice the sap dripping from this freshly cut branch.
It’s a fairly complex process that causes the sap to begin to flow in the spring. Simply put, as the tree is coming out of dormancy in the late winter and early spring water and sugars (sap) stored in the roots begin to move up the trunk to feed new leaves and buds as they emerge. This is the time of year that Sugar Maples (Acer saccharum) are tapped in the Northeast U.S. where the majority of maple syrup in this country is produced.
The sugar content of Sugar Maple sap varies between 2 and 5%, whereas birch sap is about 0.5-2%. The sap from a number of species of maple trees can be used to make syrup, as well as a few other species such as birch. In fact a quick online search yields several websites that sell birch syrup.
I collected a small cup of this sap, it had good flavor and was ever so slightly sweet. If you’re interested in harvesting the sap from your trees, small kits are available online. Our native Bigleaf Maple (Acer macrophyllum) might be a good candidate.
The tapping of trees to harvest the sap or cutting of branches which causes bleeding, hasn’t been known to cause any long term damage. The tree won’t “bleed out” or be killed by losing too much sap.