Mainline questions, wet/dry advantages?

[Atgreene]

I'm upgrading our largest sugarbush. Currently have 1000' of 3/4" that's been there for 15 years or more. Numerous 3/4 and 1/2" laterals run into it, one leg crosses under a road and does the same. All told 500 taps or so. Last year I ran my vacuum on generator at the tank. This year I've bought 1000' of 1-1/4" black to carry my vacuum diwn to the relaser and my pump can be up at my power source. What is the advantage of a wet/dry line system over keeping the vacuum line independent all the way to the releaser? Better vacuum distribution?

Also, the leader hd mainline is what I'm considering using. I didn't plan to rebuild my whole system but I went in and logged out a large area and removed everything but maples. In doing so I've decided I may as well straighten it all out now rather than put it off.

Opinions appreciated.

[unc23win]

Better vacuum distribution is the number one reason if your only running one line you can’t get maximum vacuum because the sap in the line limits the vacuum transfer. If you add a 1.25 line you will be more than doubling the amount of vacuum you can transfer. Plus your dry line can help if the wet line is frozen or maxed out. Another advantage depending how you set it up you can isolate different lines by using valves and still have vacuum to others.

[Walling's Maple Syrup]

In most applications, a dual line conductor system is beneficial because it does just what unc said. More vacuum to the taphole will make more sap.
That being said, I have had good luck with a single line conductor system (vacuum and sap in same line). My main woods is set up this way (5800 taps); big conductor lines going straight up hill with 3/4" lateral mains coming off the sides running the contours if the hill. The only way a single line conductor system will be effective is on super steep ground with no places for sap to pool. If your woods is not steep enough, a dual line system is the way to go. All my other woods except for the main woods have wet-dry systems, because they are just not steep enough.
Neil

[maple flats]

What length is that 1.25" line? If too long, you may not get good vacuum to the releaser. I have a wet/dry line on one woods and it works very well, my other woods is single line (really 2 singles, each going to the releaser.
There is a tubing notebook written by Steve Childs and published by Cornell that will give you all of the correct answers. Either system can work well but only will work at it's potential if the tubing sizes are correct. If you go too far on a smaller tubing, the pump can not transfer the vacuum to the point of use well enough and you end up getting a reduced vacuum in the system.
While I still have a few mains that are 3/4", anything I've installed in the last 8 years have been 1" (for better vacuum transfer). I suggest you get rid of those 1/2" mains (that you called laterals) because there will be very little vacuum transfer in them during times of good or better sap flow, because sap is filling too much of the space.

[DrTimPerkins]

Two comments:

1. In terms of production, wet/dry systems are associated with about a 10% improvement in sap yield, probably due to better vacuum at the taphole (faster removal of air from the tubing system).

2. In thinning a sugarbush, don't take out ALL non-maple. Leaving as little as 25% other species (and red maple counts as a different species) will reduce the incidence of insect and disease problems to a very high degree. Sugar maple mono-cultures are quite susceptible to a wide array of pests, and get hammered hard when there is an outbreak of some kind.

[Atgreene]

Thank you for all the info. Vacuum is all new to us last year, so I'm trying to bring 50 years + of sapline/gravity up to modern vacuum system standards. My biggest issue has been finding the standards to go by. I've got 300' of 1" that will be at the bottom starting at my releaser, everything else will be 3/4". All the 1/2" will go away. Eventually I will need two sap ladders, but I'm not sure my miniflood will be sufficient to handle it all. The vac pump will be 1000' from the releaser, but with all the branch lines and feeders there will be well over 4500' of 3/4 or 1" in the system. We need to cross through three different culverts under two state roads and several buried 4" sleeves I've installed on our logging roads.

As to logging, we'll never strip all the other wood, but any beech and oak I'm anxious to remove as they seem to cause the most problems in competition with the sugar maples. We don't tap any soft maples. Never have. As much as my father has allowed me free reign to upgrade and improve, soft maples are still one of his few drop-dead-won't-tap-over-my-dead-body rules. lol.

Thank you for all the info. They're forecasting a colder than normal February. For my sake I hope they're correct, I've got a lot of work to do.

[DrTimPerkins]

We don't tap any soft maples.

That was common practice in many woods years ago. On good vacuum red maples will run quite well. The sugar content isn't much lower, but with an RO that isn't a problem. We started tapping red maples about 20 yrs ago. They make up about 1/3 of our total taps at present.


Thank you for all the info. They're forecasting a colder than normal February. For my sake I hope they're correct, I've got a lot of work to do.

Same here.

[Russell Lampron]

We don't tap any soft maples. Never have. As much as my father has allowed me free reign to upgrade and improve, soft maples are still one of his few drop-dead-won't-tap-over-my-dead-body rules. lol.

About 90% of my taps are red maples on vacuum and if I didn't tap them I wouldn't be making very much syrup. My father and grandfather would never tap a red maple and when I tapped them with buckets I found out why. They tapped with buckets!

[Brian Ryther]

In most applications, a dual line conductor system is beneficial because it does just what unc said. More vacuum to the taphole will make more sap.
That being said, I have had good luck with a single line conductor system (vacuum and sap in same line). My main woods is set up this way (5800 taps); big conductor lines going straight up hill with 3/4" lateral mains coming off the sides running the contours if the hill. The only way a single line conductor system will be effective is on super steep ground with no places for sap to pool. If your woods is not steep enough, a dual line system is the way to go. All my other woods except for the main woods have wet-dry systems, because they are just not steep enough.
Neil

I have thought about his a lot. Neils yields blow PMRC out of the water. Yet he dosn't have dry lines in his main woods. Why? No leaks! You might think you are leak free, but do you go to your woods at night at freezing time and look for places where ice is forming. Most of us are making our final sap collection and are anxious to boil the days sap. Neil is looking for leaks. Vacuum gages at the releaser make us feel good but they are not the truth. Main line connections might be frozen because of a leak but the releaser Is at full vacuum potential. Dry lines will help that problem but it will not fix the leak that caused the ice dam that is blocking vacuum to a main line. I invested in a monitoring system this season this year. I can now identify main lines that shut down and loose vacuum at freeze up while the releaser is still at vacuum potential. I had no idea how many problems I have. Yet the vacuum gage at the releaser is 1/4" of the pumps potential.
On a side rant. I use dry lines with a different idea. I under size wet lines, 600 taps per 3/4" and 1200 per 1". with this method wet lines run full stream and dry lines stay dry. Sap stays cooler without air in the lines.

[GeneralStark]

"What is the advantage of a wet/dry line system over keeping the vacuum line independent all the way to the releaser? Better vacuum distribution?"

I am confused by the original question? DO you mean running two lines between the pump and releaser? Or are you talking about two mainline conductors from the releaser to the woods and taps? One for sap and one for air connected to each lateral mainline.

The responses get at the benefit of the two conductors in the woods, but two vac. lines between pump and releaser would certainly benefit as well by adding CFM transfer.

[VT_K9]

As mentioned by the General, I would eliminate all your 1/2" laterals. We have changed from 3/4" "main" and 1/2" "main" and "laterals" to 1" mainlines and 3/4" laterals. We are limiting the amount of 3/4" to the 3/4" we have left for very few new and repairs of current 3/4" which are not ready to be replaced. Our new run is going to be 1 1/4" main line with 1" laterals (maybe a 3/4" lateral on the lower portion of a ladder). The big reason for one step in size is to reduce potential ice blockages during a freeze. When you are in your woods next take a sight line down a 1/2" or 3/4" line. At what point do you see the top of the pipe dip below the bottom of the pipe...sag or snakey area. This is a potential for less vacuum transfer and high icing. Go bigger to 1" for your mains and you will see an improvement. Also, we use SS fittings since they have a reduced area for turbulence, diameter close to full pipe, and the barbs hold better. When we looked at going up one size we looked at the cost of the fittings and it was not much more. These are 15 year returns, not annual replacements like taps.

In thinking about your statement the General and I are hung up on. I my family's bush we run two collection tank locations (Sap Shacks). One is 725' and the other is 1200' away from the Sugar House where the vacuum pump is. We run 1 1/2" vacuum line (blk poly) to the 725' shack and since we are in the process of upgrading a lot this year we will likely use a sap puller on the 1200' run this year. Then will come the research of 1 1/2" vs 2" for that vacuum run. I believe the 1 1/2" will be sufficient for the 1200' run. If the cost is not much more then we may go 2" or a combination (I have a good source for 2" black poly but am limited to 100' rolls). I feel the extra cubic storage area could help in the case of releaser dumps, ladders, or leaks.

Finally to put my .02 on your primary questions of the wet/dry...we don't have one...yet. We thought about using 1" on the new mainline (about 1000') and then adding a 1" or 3/4" dry line next year or year after. In older mainline we had quite a bit of icing last year and what a pain it was. I know a dry line would have helped a lot in vacuum transfer AND a place for the sap to travel when the wet line is frozen (depending on how they split at the releaser). SO there are two advantages in my research and that is the transfer of vacuum to the bush and sap when the wet line is frozen. The frozen lines will thaw as sap flows through and around the ice and as the day warms. We may add a dry line for a good portion of the older mainline and may still put on in with our 1 1/4" lines. This will come after expanding to 800-1000 taps (from 400 now) and building a new Sugar House. The new Sugar House and equipment will allow us to be in the woods more making the most out of what we have.

Good luck,

Mike