steep hill tubing

[briduhunt]

I have access to a large sugar bush with some old growth trees but my concern is how steep the hill is. I have a plumbing back ground and we were always having a problem with tdrain lines having to much of a pitch and we had to use 1/8" drop per foot. I know this is not drainage but I am concerned that it will not drain properly using gravity. Any suggestions would be appreciated.

[vtmaplemaker]

on gravity... let it fly.. there is no such thing as too steep. worse case, vent the end of the main line.

[ennismaple]

Steep is good. Set it up like you would for a wet/dry vacuum system so your trunk mainline goes straight uphill, your 3/4" mainlines go across the hill at a 2-5% slope and your laterals run straight up and down.

[maple flats]

In plumbing the steepness matered because the liquid could leave the solids behind. No such problem with sap. The steeper the better on laterals. Just run your main at 2-4% slope and run the laterals as steep as you can navigate.

[DrTimPerkins]

In plumbing the steepness matered because the liquid could leave the solids behind. No such problem with sap. The steeper the better on laterals. Just run your main at 2-4% slope and run the laterals as steep as you can navigate.

With gravity, steep lateral lines is good for developing natural vacuum. Along the same lines, keep the # taps on each lateral line high (15-30+ depending upon tree size). By doing this you will develop quite good natural vacuum in the system.

DO NOT VENT either the lateral lines or mainlines. If you do vent laterals, it will totally negate the natural vacuum effect. Venting mainlines will reduce the effect somewhat, but not have nearly as large a negative impact.

[vtsnowedin]

With gravity, steep lateral lines is good for developing natural vacuum. Along the same lines, keep the # taps on each lateral line high (15-30+ depending upon tree size). By doing this you will develop quite good natural vacuum in the system.

DO NOT VENT either the lateral lines or mainlines. If you do vent laterals, it will totally negate the natural vacuum effect. Venting mainlines will reduce the effect somewhat, but not have nearly as large a negative impact.
Glad to see you back Doc. How was your research season and how well did the kids do at the Odyssey of the minds?

[DrTimPerkins]

Glad to see you back Doc. How was your research season and how well did the kids do at the Odyssey of the minds?

Research season went quite well...despite the weird season. Will be presenting the results at various meetings over the next year, starting with Goodrich Open House (April 23), then Leader Evaporator Open House (April 30, May 1), then Bascombs Open House (May 7-8).

Odyssey of the Mind also went well. We had 110+ teams (5-7 kids + 1-2 coaches each) from all around the state and about 160 volunteers. 25 of these teams qualified and are headed to the Odyssey of the Mind World Finals at Michigan State University in late-May. My wife, daughter, and I, as well as 11 other Vermont volunteers go there for the week as officials. Great program if any of you have kids vt.odysseyofthemind.org www.odysseyofthemind.org Will be around 800 teams from all over the U.S. and about 25-30 other countries at World Finals.

[farmall h]

briduhunt, steep is goooood. Visualize it the best you can as ennismaple stated. You wanna see steep? Google Earth: Calendar Brook Road, Sutton, Vermont. I am located in the valley next to the brook...maple orchard straight up! You know its steep when you have to grab the trees around you to tap.:) From the sugarhouse my elevation starts at 940ft and climbs rapidly to 1200 ft with in a 10 acre stretch. My mainline goes directly into the sugarhouse from rafters.

[vtsnowedin]

Research season went quite well...despite the weird season. Will be presenting the results at various meetings over the next year, starting with Goodrich Open House (April 23), then Leader Evaporator Open House (April 30, May 1), then Bascombs Open House (May 7-8).

Odyssey of the Mind also went well. We had 110+ teams (5-7 kids + 1-2 coaches each) from all around the state and about 160 volunteers. 25 of these teams qualified and are headed to the Odyssey of the Mind World Finals at Michigan State University in late-May. My wife, daughter, and I, as well as 11 other Vermont volunteers go there for the week as officials. Great program if any of you have kids vt.odysseyofthemind.org www.odysseyofthemind.org Will be around 800 teams from all over the U.S. and about 25-30 other countries at World Finals.
A great program. Been there, done that. They are out of college now but two of three are working in the medical research labs at UVM. I want them to gene splice me a sugar maple with a sugar cane gene to get sap at nine percent.:) Failing that I've told them I would settle for a cross of witch grass roots with a beefsteak tomato top. Not any weirder then the stuff they are really working on.
Sorry to deflect the thread.
Mine is steep north facing and gravity and this weird year it just seemed to sit there bound up. Neighbors bush on vacuum and a south east pitch ran three to my one.

[Rhino]

Now i am wondering after i read 15-30 taps for each lateral if I am restricting our sap per tap. On our gravity tubeing, we run 5 taps per line and 3 lines per 18 gal. tote. The 3 lines all connect together where the tote sits, and we have 3 down spout lines that go into the tote. Would we be better off to have 15-18 taps on one line running into the tote? We don't have slope, but i could start the end line high and make slope. With only 5 taps per line i still wonder about venting the top ones. If you pull out the top tap right now after the season, a steady stream of sap runs out the end tap until the line clears. what is up with that? I would think if it was vented the lines would be more free in the morning so it wouldn't take so long to thaw out or the trees wouldn't have much sap to suck back into the holes. At 5 taps per line the natural vac. can't be much if any. I can understand with 20-30 taps per line there would be enough liquid to create vac. What would be the best way to get the most sap per tap. like i wrote, we don't have billy goat hills to work with so my slope would be 5 foot up in the tree running down to lets say 2 feet to the tote. Any feedback appreciated.

[DrTimPerkins]

<snip>If you pull out the top tap right now after the season, a steady stream of sap runs out the end tap until the line clears. what is up with that? I would think if it was vented the lines would be more free in the morning so it wouldn't take so long to thaw out or the trees wouldn't have much sap to suck back into the holes.

General rule (slight underestimate) is that 1 ft of water = 1" Hg. That is only when the sap is actually running though. With only 5 ft, you probably don't have enough natural vacuum to worry about it.

In terms of venting though, repeated research studies done in may places since at least the 1950s through the 1990s have shown that venting of tubing will result in the sap getting from the tree to the tank faster, but you'll get far less of it. This is due to two factors: natural vacuum, and venting pulling in microbe laden air which cause taphole drying.

A lateral line runs nice and fast when you pull a spout to vent it. This is because the line that was filled with sap empties quickly, and it looks like you're going to get so much more sap faster if you vent. You will, for about a minute. After the tubing empties, what you'll see if you watch for a while is that the tree drips sap into the tubing, and the sap drips just as slowly out the other end into the tank.

The decision is yours though....get your sap to the tank a little faster and get 33-50% less, or wait a little and get more.

[vtsnowedin]

Now i am wondering after i read 15-30 taps for each lateral if I am restricting our sap per tap. On our gravity tubeing, we run 5 taps per line and 3 lines per 18 gal. tote. The 3 lines all connect together where the tote sits, and we have 3 down spout lines that go into the tote. Would we be better off to have 15-18 taps on one line running into the tote? We don't have slope, but i could start the end line high and make slope. With only 5 taps per line i still wonder about venting the top ones. If you pull out the top tap right now after the season, a steady stream of sap runs out the end tap until the line clears. what is up with that? I would think if it was vented the lines would be more free in the morning so it wouldn't take so long to thaw out or the trees wouldn't have much sap to suck back into the holes. At 5 taps per line the natural vac. can't be much if any. I can understand with 20-30 taps per line there would be enough liquid to create vac. What would be the best way to get the most sap per tap. like i wrote, we don't have billy goat hills to work with so my slope would be 5 foot up in the tree running down to lets say 2 feet to the tote. Any feedback appreciated.

Sounds familiar. I have plenty of slope on the laterals with from ten to fifteen taps each but I may have shot myself in the foot by putting my main line on a minimum slope trying to catch as many taps as possible. I also have orphan lines that run straight into fifty five gallon barrels at the road side. some of these ran very well for one day then just sat there. As I am cleaning these lines from the top down I put about a quart of hot water into the top tap then plug it off. By the time I get to the third or fourth adding a quart to each tap when I pull the tap I can hear it sucking air and all I have to do is stick the tap into the five gallon pail of hot water for the gravity vacuum to suck up its quart. Maybe it was just a really really bad year and nothing but a good vac pump would work but I'm going to ponder my next move for quite a while.

[Brian Ryther]

I was a witness to natural vacuum this season. I have a few lines that have 30+- taps that go to barrels. I has a chance to walk one of these lines this season while it was running. As I walked the line I came to about the 25th tap when I heard a hissing. I had a tee fitting that the drop line was not perfect and the natural vacuum was causing it to hiss just like tubing on a vac pump. At that moment I became a believer.

[driske]

Rhino,
You got to go with Doc Tim on this issue. Any perceived benefits of venting are delusionary. I played around with all this stuff 25 years ago. Vented ground lines, vented and unvented suspended systems, sap suckers,etc.etc.etc. If somebody had an idea I tried it.
What you are seeing when you pull that tap and the sap moves away, is the same phenomenon witnessed when a tap on an active vacuum system is pulled. Only it takes place relatively slowly. Yet, faster than the slow creeping flow of an unvented natural vacuum line. Erroneous short term conclusion;vent the line to speed it up.
Go with sap in the tank at the end of the day as your guide. Any slight amount of vacuum, generated by negative head, will out yield vented lateral lines.
If it's any consolation, I've been unsuccessfully trying to sell the unvented concept to one of my neighborhood sap patrons for years. He patiently pats me on the shoulder, and tries not be be condescending to his dottering old misguided neighbor. Then proceeds to up his tap numbers, and whine about another poor year. :rolleyes: :lol:

[Rhino]

O.K......I'm sold on the idea of not venting any gravity lines, but what do you guys think about my 3 lateral branch lines going to a tote, instead of one longer one with the same amount of taps. (around 15-18). Sounds like i would get more natural vac. with the one longer line. I know I wouldn't hear hissing the way i have it now if a T came apart or a rodent took a bite out of it. Or would the work and time switching it over to one line networks really be worth it. Thanks

[SilverLeaf]

The decision is yours though....get your sap to the tank a little faster and get 33-50% less, or wait a little and get more.

This statement grabbed me. Dr. Tim - in terms of sap production, how might a vented system compare to a system all on buckets? I would have expected them to be about the same, because they're both relying solely on gravity, but this statement seems to indicate that a vented system would actually produce less per tap than if the thing were set up on buckets, because on buckets don't you get about 80% of what you'd get on vacuum?

Am I understanding this right?

[PerryW]

I would think that ...

In a typical sugarbush, UN-vented laterals may give you a few percent more sap, but probably not 33-50%.

My 600 tap gravity bush is ideal for natural vacuum with 300 feet of vertical over a hill about 1200 long, yet still I get little or no natural vacuum of about half of my taps for the following reasons:

1) Many of my laterals are 10 or less taps on the larger-diameter rigid tubing and the sap never gets going enough to fill the laterals and start the natural vacuum effect.

2) Even on the laterals with 20-35 taps, the lower taps do not generate nearly as much natural vacuum as the upper taps.

3) Many of the laterals simply don't have enough vertical to produce much head.

Also, the natural vacuum doesn't kick in until things start flowing well. On days where the sap weeps out over an extended run, the flow rates are minimal and again; the laterals just run like water in a gutter and don't fill the pipe.

BUt for me, a few percent is better than none and any vents are just another potential place for sap to leak out of when the laterals are frozen up downstream.

Another advantage for unvented gravity laterals is that...

You can find leaks by observing the percentage of air bubbles in the saplines. If there is mostly air in the laterals flowing fast with occasional pockets of sap; you have a leak. You can find it by walking up the lateral until you hear the hissing sound or notice that the lines are running slower with about one half sap and one half air in the laterals.

[DrTimPerkins]

This statement grabbed me. Dr. Tim - in terms of sap production, how might a vented system compare to a system all on buckets? I would have expected them to be about the same, because they're both relying solely on gravity, but this statement seems to indicate that a vented system would actually produce less per tap than if the thing were set up on buckets, because on buckets don't you get about 80% of what you'd get on vacuum?

Am I understanding this right?

I'm sorry if I was unclear. Buckets and vented gravity tubing will do about the same. Unvented gravity tubing on a good slope, set up properly with a good number of trees on each lateral (and typically longer laterals), will, on average, yield signficantly more sap than trees on a vented system. This is "primarily" due to natural vacuum. What you'll find though in a system like this, is that leaks will greatly reduce the effect, the same as with pump-derived vacuum. So if you have a decent site and setup for natural vacuum, you need to be diligent about fixing leaks in your system as much as the vacuum-pump producers.

[steve J]

My laterial lines currently all feed to 3/4 main line. But as I have read these treads I see that on a gravity system which I have having 25 or 30 taps is better then 10 or 12. I am assuming that if I put some Y connectors in and allowed some lines to merge into 30 tap runs that I probably would created more vaccum?

[PerryW]

DrTim,


I always figured that vacuum pump setup following all the rules would roughly double sap production but ....

Do you know if there is some some of chart that estimated Overall Sap yield vs. Inches of Vacuum?

[PATheron]

Perry- If you run 20 inches of vac your going to far out produce any gravity setup unless you just happen to have a great gravity year and even then youll beat it by a lot. Anything over 20 inches you gain 5% more sap for every inch over 20. Theron

[DrTimPerkins]

Do you know if there is some some of chart that estimated Overall Sap yield vs. Inches of Vacuum?

Yield will vary for a lot of reasons, vacuum being one of them. There are several studies that have been done. One of the more recent is available on the UVM Proctor Maple Res Ctr website. http://www.uvm.edu/~pmrc Click on
Vacuum Sap Collection: How High, or Low, Should You Go? on the "Recent Publications" link on the right side.

[farmall h]

Steve J, yes that would work with out too much hassle.

[adk1]

I have been told to stay away from Y fittings if at all possible

[3rdgen.maple]

I have been told to stay away from Y fittings if at all possible

Dont know why adk1 they are very handy and have a purpose.

[adk1]

Just stating what the good DR. has told me. I am sure he can/will provide an explanation. He didnt say dont use them, but said use them very sparingly.

[adk1]

I'm sorry if I was unclear. Buckets and vented gravity tubing will do about the same. Unvented gravity tubing on a good slope, set up properly with a good number of trees on each lateral (and typically longer laterals), will, on average, yield signficantly more sap than trees on a vented system. This is "primarily" due to natural vacuum. What you'll find though in a system like this, is that leaks will greatly reduce the effect, the same as with pump-derived vacuum. So if you have a decent site and setup for natural vacuum, you need to be diligent about fixing leaks in your system as much as the vacuum-pump producers.

I have a newly found patch of large maples (I ahve explained this in another post). There are 24 and the slope is pretty decent. Unfortunatly they are located the farthest away from my storage. Anyways, I have two options. Option #1. Run one lateral line from my mainline to an end tree that would be 280' that would pick up 5 trees. At about the 125' mark, I would add a Y and run a lateral off of that to pick up 19 more trees.
Option #2 is to run the one 280' lateral to pick up the 5 trees. then run a second lateral from the mainline to pick up the 19 trees.

Also, all of these trees are 2 tap trees.

[DrTimPerkins]

I have a newly found patch of large maples (I ahve explained this in another post). There are 24 and the slope is pretty decent. Unfortunatly they are located the farthest away from my storage. Anyways, I have two options. Option #1. Run one lateral line from my mainline to an end tree that would be 280' that would pick up 5 trees. At about the 125' mark, I would add a Y and run a lateral off of that to pick up 19 more trees.
Option #2 is to run the one 280' lateral to pick up the 5 trees. then run a second lateral from the mainline to pick up the 19 trees.

Also, all of these trees are 2 tap trees.

Run two laterals. You've got 19 tree, with 38 taps on one line, and 5 more trees, with 10 taps. You should be looking for 25-40 taps per lateral line on gravity tubing. With more than that (if you used a Y), you'd be overtaxing the lateral line (nobody likes to be overtaxed :) ). Would be better if you could make it closer to 25/25 for the two lines.

We have 2,707 taps in our sugarbush....not a single Y on any lateral lines (although ours is a vacuum setup). Many of these lines were done by commercial installers, so it isn't just us doing it this way.

[adk1]

ok, will do my best. I would only be saving like 50' of lateral line and another saddle by running the one line, but if it will be more efficient for sap flow to run two then that is what I will do.

[WESTVIRGINIAMAPLER]

ok, will do my best. I would only be saving like 50' of lateral line and another saddle by running the one line, but if it will be more efficient for sap flow to run two then that is what I will do.

Which would only save you about $ 7.