Okay, say that title 5 times without tripping over your tongue.
Sapsuckers do, indeed, suck sap. It’s their main food source, though they also dine on insects, especially ones attracted to sap.
Sap wells are the holes that yellow-bellied sapsuckers drill into live trees. Once you’ve seen sap wells, you can’t mistake the lines of organized holes for anything else.
In the spring sapsuckers drill deep round holes (into the tree’s xylem for the botanically inclined) to catch the sap rising from the roots up to the branches.
Later, after the tree has leafed out, they drill shallow, rectangular holes (into the phloem) to catch the sap being sent down the tree to be stored in the roots.
Yellow-bellied sapsuckers are frequent visitors to our yard. For years they have dined on the sap from lilac, saskatoon and mountain ash.
This year, for the first time, I caught a sapsucker family feeding on a large aspen.
Search YouTube if you’d like to see these suckers in action. 🙂
Yellow-bellied sapsucker Sphyrapicus varius
Aspen Populus tremuloides