Number of taps per tree review, please.

[jimmol]

With the frigid weather in southern Michigan, I am spending time reading articles about tapping since I do not want to tap till it warms enough to flow, probably the March 8th weekend. There is a vast difference in the size of the tree for the 2nd tap, 18 - 24 inches, from my readings. Even articles as recent as 2016 have said 18 inches. I have some maples that have reached the 18 inch mark, but I thought years ago I read a thread that suggested waiting till 20 inches. Since the search engine is limited - I tried searching taps per tree - I am turning to those who have more experience and expertise.

What is the recommendation for tree size to add a second tap?


Thanks for your input.

[Cjadamec]

Along the way reading things here I found an easy rule to follow on the second tap per tree. It is not as scientific as you might want but it works for me.

If you hug the tree and your hands touch its too small for a second tap. If you cant touch your hands when you hug the tree it's big enough. If your hands are a mile apart you can probably do 3 taps if you want.

[berkshires]

Along the way reading things here I found an easy rule to follow on the second tap per tree. It is not as scientific as you might want but it works for me.

If you hug the tree and your hands touch its too small for a second tap. If you cant touch your hands when you hug the tree it's big enough. If your hands are a mile apart you can probably do 3 taps if you want.

This is what I use, and my guess is that this is probably as good a rule as any, since the "real" rule would be much more complicated than a single number.

I suspect that if you wanted to have a real rule, the main other factor that would affect it is how quickly the tree is growing. If it's in dense forest, I'd guess closer to 24" or more might be best, whereas if it's all alone, on a south-facing slope, you could probably put in a second tap at 18" with no problem.

[maple flats]

While not an official rule (mine are all on vacuum) 10" thru 19" 1 tap, then if the tree looks healthy I put 2 taps at 20" plus, if not a good looking tree (major broken off limb or damaged area) it still only gets 1 tap. I never on vacuum have more than 2 taps.
Back when I was on gravity, I did 1 on 10-17", 2 on 18-27" and 3 on over 28". I still used my trees with defects guideline.

[Hop Kiln Road]

Obviously each tree is a little different, but I think generally there is a tendency to over tap. Studies have also shown the yield from a second tap is less than the first.


Surface Area of a Cylinder

Length of Cylinder 18"
Tree Diameter 8 10 12 16 20 24
Sq In of Surface 553 772 904 1307 1759 2262

Length of Cylinder 24"
Tree Diameter 8 10 12 16 20 24
Sq In of Surface 703 911 1130 1608 2136 2714

Average Area of Stain (3X18?) 54
Average Growth Rate 2" in 20 yrs
Sustainability of 24" Cylinder One Tap 12"
Two Taps 20"

Factors to Increase Tapping Sustainability of Orchard:

1. Tree Growth Rate; Highly Variable - Site Index, Crown Area, Diameter Class
2. Tapping Depth
3. Tap Diameter

[DrTimPerkins]

Studies have also shown the yield from a second tap is less than the first.

That is correct for trees on vacuum. On gravity the yield from a second tap (assuming the tree is large enough) is nearly double the first tap. Because vacuum will pull sap so much further within the tree, a second tap will not yield a doubling of sap yield. Rather, the amount of sap increase depends upon the vacuum level and the size of tree. So at good vacuum (mid-20s), the yield from a 16" tree might run around 60-65%, but increases as the tree diameter increases. Then again, the yield from the first tap for a tree on vacuum will far exceed the yield from a tree on gravity (for the same size tree).

[jimmol]

Many thanks for information. Now that someone said it, I remember someone saying about the health of a tree. Based on all that is said I may have one more tree I can add a second tap.

Thanks for the update on vacuum, though I do not know how much my Aquatech 8800 really contributes but it cannot hurt.

Just waiting for a few days above freezing.

[DrTimPerkins]

Just waiting for a few days above freezing.

Aren’t we all.