depth of tap hole

[ir3333]

Does the depth of the tap hole have any effect on the volume of sap flow?

[DrTimPerkins]

Yes.

On gravity, tapholes of 2.5" deep are recommended. On vacuum, tapholes of 1.75-2.00" deep are sufficient.

Those values include bark. If you're only tapping large, thick-barked trees, a little deeper is probably OK. Beyond that, any gain in sap is negligible, however you are making a larger wound in the tree that reduces tapping sustainability in the long-term.

There is an article coming out on relationship of tapping depth to sap yield and sugar content in the next issue of Maple Digest.

Several videos at https://www.youtube.com/c/UVMProctor...hCenter/videos have info on this and other variables affecting sap yield. I'd suggest https://www.youtube.com/watch?v=3wXxByeuc48&t=384s as a place to start

[berkshires]

Yes.

On gravity, tapholes of 2.5" deep are recommended. On vacuum, tapholes of 1.75-2.00" deep are sufficient.

Well now that is interesting!!! I had always thought that 1.5 - 2" was the limit (not counting heavier bark). I thought more than that and you don't get much benefit compared to how much more of an injury you do to the tree. Maybe I was following the limit for people on vacuum/tubing? Thanks for the tip!

And I'll look for that article when it comes out.

GO

[berkshires]

There is an article coming out on relationship of tapping depth to sap yield and sugar content in the next issue of Maple Digest.

Several videos at https://www.youtube.com/c/UVMProctor...hCenter/videos have info on this and other variables affecting sap yield. I'd suggest https://www.youtube.com/watch?v=3wXxByeuc48&t=384s as a place to start

I would love to learn more about tapping depth on gravity, but I don't think any of the videos you suggested mention that. Are there other resources you could suggest?

Thanks again,

GO

[DrTimPerkins]

I would love to learn more about tapping depth on gravity, but I don't think any of the videos you suggested mention that. Are there other resources you could suggest?

The North American Maple Syrup Producers Manual 2nd Edition (aka the Sugarmaker's Bible) https://holmes.osu.edu/sites/holmes/...full%20pdf.pdf
Tapping guidelines around page 85+

New version (3rd edition) coming out in a year or so (working on one of the new chapters today in fact), however most of the material on gravity sap collection (buckets, bags, tubing, not 3/16" gravity-vacuum) is still valid and not going to change much.

[ir3333]

Good video. Outside sapwood caries more and sweeter sap!
I'll be much more careful when i tap now.

[BoerBoel]

On gravity, tapholes of 2.5" deep are recommended. On vacuum, tapholes of 1.75-2.00" deep are sufficient.

Does 3/16" gravity-vacuum fall under the gravity or vacuum depths?

[DrTimPerkins]

Vacuum is vacuum is vacuum....however it is generated.

[edward]

[QUOTE=DrTimPerkins;389972]Yes.

On gravity, tapholes of 2.5" deep are recommended. On vacuum, tapholes of 1.75-2.00" deep are sufficient.

Those values include bark.

I will be using 5/16 taps with half on buckets and half on gravity. Tapping mostly old trees with thick bark. How far INTO THE WOOD should I drill for a gravity or bucket tap?

Thank you,
First-time tapper
Central Mass on NH border.

[DrTimPerkins]

On gravity, tapholes of 2.5" deep are recommended.

Those values include bark.

if the bark is really thick, you can scape a little off, or, if the trees have been tapped/overtapped for a while, go 2.5" deep including bark. If EVERY tree has thick bark, then you can maybe go 3" (INCLUDING BARK) if the trees haven't been tapped much previously.

Not sure what you mean by half on "gravity". When I say gravity, I mean buckets, bags, or gravity tubing, NOT tubing with ANY type of vacuum, whether pumped or natural vacuum.