Mid-winter is my favorite time to harvest birch for sweet-flavored food and warming beverages. Birch trees are easy to identify in winter thanks to their distinctive bark. The bark is an eye-catching white, or pale yellow, slashed with dark horizontal marks, and frequently found peeling off of the tree in papery strips. Older birch trees may have much darker bark, but the younger branches will still flash silvery pale hues. Check the leaf buds and you'll find that they are alternately arranged on the twigs (in a hand-over-hand pattern rather than in pairs). Birch trees can grow from 30 to 50 feet tall, depending on the species of Betula, but are often shorter. They often grow near water.
At this time of year, there are three ingredients I get from birch trees: tea from the twigs; a tea, spice, and flour from the inner bark; syrup from the sap.
Although you could prune off a few twigs here and there without harming the birch tree, you probably don't have to. Birch wood tends to be brittle, and smaller branches almost always break off the trees during winter storms. Just look on the ground soon after a storm and collect the windfall. That's also the best way to collect the cambium (inner bark). Take one of the thicker windfall branches and come in at an angle with a pocket knife. As you pare it down in a strip you'll be able to clearly identify the papery outer layer, softer inner bark layer, and hard central wood layer. It's that middle layer you want, but fine if the outer layer is clinging to it. Birch cambium is pale when first exposed to air, but then rapidly becomes a reddish-brown color. Note that stripping bark full circle around the main trunk can kill a tree, which is why I recommend collecting it from storm-broken branches instead. Both the twigs and the inner bark have a light wintergreen scent that is another one of the identification characteristics for birch.
Birch trees can be tapped just like maple for their sweet sap, and that sweet sap can be boiled down to make birch syrup. The birch "sugaring" season starts just as the maple-tapping season is tapering off, around late March. The reason you see more maple than birch syrup for sale commercially is that the ratio of sap to syrup is far greater with birch (you need about 100 pints of birch sap to get 1 pint of birch syrup, vs. closer to 40:1 for maple). There is a right and a wrong way to tap trees for sap. Done correctly, the tree will remain healthy and can be tapped again in following years. Done incorrectly, you could kill the tree. Instructions for how to do it right are here.
Break small twigs into short pieces. Simmer them in water for about 5 minutes. Strain out the twigs and enjoy as a hot beverage. When using the inner bark for tea, don't simmer it as you would the twigs – too much of the aromatic goodness evaporates away. Instead, put some of the inner bark (about a small handful per quart of water) into a heat proof container such as a canning jar. Pour boiling water over, cover, and let steep for 10 – 20 minutes. Strain, briefly reheat if necessary, sweeten if desired. To use the inner bark as a spice or flour, first dry and then grind it. Taste a pinch and decide if you think it is strongly flavored enough to use as a spice, or if you will combine it with other flours in baked goods. Use the syrup in any way that you would maple syrup...but expect a very different, unique, and pleasant taste! Also use it (or the sap) to make birch beer and wine.
Leda Meredith teaches foraging and food preservation skills internationally. You can find out about her upcoming classes and her books, watch her foraging and food preservation videos, and find her food preservation recipes and tips.