Originally Posted by
DrTimPerkins
Tapholes on gravity buckets/bags typically last about 6 weeks unless you get really hot weather during that time, which could dry out tapholes abruptly. That timeframe is true of red maple and sugar maple. I suspect that some of you are at or past that time if you tapped in early-February. In short, those tapholes are done for the season. Tubing (with good sanitation) will get you a bit more. Vacuum tubing with excellent sanitation will almost double that time as long as weather conditions are not terribly unfavorable.
One thing we've found in our measurements of red maples on vacuum over the past few years is that they are extremely variable (it is likely to be the same for gravity collection). One taphole will produce huge amounts of sap, the next one very little. This is true for trees that are next to other, or even in two tapholes in the same tree. Why is this? We aren't sure yet, but it has nothing to do with direction of tapping or whether we tap higher or lower (above or below the lateral line). UVM PMRC (mostly Dr. Abby) will be doing a good amount of more research with red maple over the next couple of years.