How high

[twitch]

How high is to high for a tap?

[MainelyMaple]

I don't believe you can tap too high, Ive got a few taps that I need to stand on the wheeler to tap. I needed the height to keep the grade

[DrTimPerkins]

On gravity, tapping lower is better. On vacuum there is less need to tap low, but lower is still better, although it is important in both cases to utilize the full tapping band to avoid cluster tapping.

In gravity sap collection, almost all of the sap movement during exudation (flow) is downward. Think of a tree as a hollow pipe stuck in the ground and filled with water. If you drill a hole half way up, you'll get a lot less water than if you drill the hole down closer to the ground. On vacuum, it doesn't matter quite as much because you can pull the sap upward too.

[twitch]

Thanks for the explanation Dr. Tim. The reason i asked is I remember A few taps that were already pretty high that i had to shovel down to last year and drill a tap hole down by my feet **** wind drifts I always hope for just a little rain on top of each snow storm.

[vikingHB]

On gravity, tapping lower is better. On vacuum there is less need to tap low, but lower is still better, although it is important in both cases to utilize the full tapping band to avoid cluster tapping.

In gravity sap collection, almost all of the sap movement during exudation (flow) is downward. Think of a tree as a hollow pipe stuck in the ground and filled with water. If you drill a hole half way up, you'll get a lot less water than if you drill the hole down closer to the ground. On vacuum, it doesn't matter quite as much because you can pull the sap upward too.

Dr
I'm on gravity, and we get quite a bit of snow so at my anchor maple the tap is approximately 48" off the ground (actual earth). What should the slope be in order to create some vacuum effect on my lines, which have 15 -20 taps per run? I currently have approx 5 degrees. Should I try to lower my taps for better sap volume?

[Flat Lander Sugaring]

my ex bro in law said when he was a young kid(now 51) him and his grandfather would have to take a 12' step ladder into wood after sugaring to get the buckets off the trees.

[DrTimPerkins]

I'm on gravity, and we get quite a bit of snow so at my anchor maple the tap is approximately 48" off the ground (actual earth). What should the slope be in order to create some vacuum effect on my lines, which have 15 -20 taps per run? I currently have approx 5 degrees. Should I try to lower my taps for better sap volume?

To get decent natural vacuum (which will only occur when sap is running), you need long laterals, running downhill, with lots of taps (25-50) per lateral (NOTE: this is VERY different than the recommendations for vacuum tubing). Slope is not terribly important except that it gains you a height differential. What is important is the difference in height from the inlet (spout) to the outlet of the lateral line. For each foot of drop in the line, you'll get a little less than 1" Hg, when the sap is running and the tubing (laterals) are full of sap. Ideal situation is to have your taps at the top of the hill, a long lateral run downhill after those trees, and the tank at the bottom of the hill at least 30' in elevation lower than the last tap on the slope (the tap closest to the tank). It is important that you don't vent....and that you keep the system very tight. A leak will kill your natural vacuum (or your pumped vacuum).

[SeanD]

Doc,

This helps a lot for the gravity tubing I'm going to try out for the first time this year. I have a cluster of about 20 taps about 200' from my barrel/SH. Then it's a very gradual drop in elevation, so I'm going to have to help it along in spots by putting the tubing up high, but I should be able to get 5%.

When you say not to vent, I assume you mean at the high end. Or should I keep the system closed at the barrel end too? I thought if I vented the barrel, it would keep the sap from having to push against the air in the barrel.

Also, will the number of bends make a difference on this kind of system? Or is there a certain angle to avoid making? On the way down to the barrel, I can veer off and pick up a couple of big producers.

Thanks,
Sean

[DrTimPerkins]

When you say not to vent, I assume you mean at the high end.

Also, will the number of bends make a difference on this kind of system?

Correct. Do not vent at the high end of the system (or anywhere along the system) except at the barrel end.

Number of bends not important (as long as you aren't crimping or heading back uphill).....it is the amount of height you have that is important.

[adk1]

good to know. I have well over 30' drop from start of mainline to end of mainline. Much more for the taps

[SeanD]

Yes, very good info. Thanks!

How far can 5/16" tubing be pulled between trees/support when it is full of sap to avoid sags at a 4-5% grade?

Thanks,
Sean

[DrTimPerkins]

How far can 5/16" tubing be pulled between trees/support when it is full of sap to avoid sags at a 4-5% grade?

Depends upon how tight you pull it, and how many trees you zig-zag around. You don't want to pull it so tight it'll come off the fittings (would require a LOT of pulling in most cases). Zig-zagging around trees (and using them as support) will help to avoid sags by providing some additional support. In some cases, it's also useful to do this because you can then adjust the height a bit by moving them up and down along the trunk as dictated by snow depth. Finally, there are some people who feel that you should only zig-zag on the south sides of trees, as putting lines on the north side may not allow them to thaw out in the shadow of a large tree, creating an ice blockage in that spout on marginal days. Going downhill will help alleviate any problems with minor sags (cause they're still going downhill even if they sag a little). Also, if you're ever going to be on vacuum, don't EVER spin the fitting on the tubing (harder or impossible with semi-rigid or grip tubing, easier on rigid tubing), as this will create a spot where there will be a leak. If ever in question, cut the fitting out, and put a new one on (and usually you shouldn't try to cut the fitting off the tubing, as you'll score it and create a place where it'll leak). These issues are more problematic the higher your vacuum level.

[SeanD]

Thanks. I have a tubing tool that should help avoid any spinning.

There are a couple of spots where the tubing could run across an open area for about 45-50 feet. Should I plan on a stake or something to help lift the line or plan another route? I'm picturing what happens with a rope or a clothesline where no matter how hard I pull there will be a sag. Is there a rule of thumb for the different types of tubing as to how far you can run without a tree or some kind of support?

Sean

[treehugger]

Dr. Tim or any other expert,
What you said about long laterals with a lot of taps falls in-line with what some of the "less techy" operations I have spoken with. I have been getting alot of flack from most Leader dealers and friends in the maple industry for putting 20+ taps on my gravity system. It actually made me cut back on my taps per lateral to keep it in the 20'ish range. Another thing I have been getting flack for is using 1/2" mainline which was recommended by a less techy leader dealer. Now after reading your comment I am wondering if I should have kept the laterals bigger, around 30-50 per line range. I have alot of gravity on my side. My mainline is around 1150' to the tank/saphouse with around 300' or more of vertical drop (per topographic map). The laterals come off some real steep faces (have to walk sideways to work the area) that connect to the 1/2" mainline positioned way below the laterals. I have 7 laterals connecting to mainline, most of which are on the top portion of the system. Do you think I have been steered in the wrong direction with the 20 tap average (they even wanted me to go less, like 10 taps per lateral) or should I have ran a very long zig zag for the laterals and cut the number of laterals in half? Thanks

[DrTimPerkins]

20 taps on a lateral is fine for gravity, and will result in some natural vacuum. You could add more, HOWEVER the problem is that when you get too high, you can restrict the amount of sap that CAN flow through the line. With 5/16" line, it is difficult to achieve a natural vacuum that is very high. Don't think you got bad info, just a tad on the conservative side.

[farmall h]

1/2" mainline is fine for gravity. 20 taps per lateral is probably the max I would go. We used to be on gravity for many years and had lots of 1/2" mainline throughout the woods that connected to 3/4" and into the sugar house. Very steep woods. Now we are vacuum and have been upsizing mainlines and reducing lateral taps to 5-10. Rome wasn't built in a day! Maybe if I had Ceazar's(sp) $. :lol:

[farmall h]

[QUOTE=DrTimPerkins;169857]Correct. Do not vent at the high end of the system (or anywhere along the system) except at the barrel end.

Make sure the tubing at the barrel is NOT submerged in the sap.