On a healthy tree if you keep within the tapping guidelines, you can tap every year. Issues come in to play if you get hit hard with Forest Tent Caterpillars, but even then, if it's only a light concentration you can tap, if the trees are hit 2 years in a row, let that tree rest a year before resuming tapping.
Dave Klish, I recently ordered a 2x6 wood fired evaporator from A&A Sheet Metal which I will be converting to oil fired
Now have solar, 2x6 finish pan, 5 bank 7x7 filter press, large water jacketed bottler, and tankless water heater.
Recently bought another Gingerich RO, this one was a 125, but a second membrane was added thus is a 250, like I had.
After running a 2x3, a 2x6, 3x8 tapping from 79 taps up to 1320 all woodfired, now I'm going to a 2x6 oil fired and a 200-425 taps.