Gravity feed lines

[Tapmealot]

hey everyone im new. just wondering about your thought on gravity feed lines. i have some perfect locations taht would work well but wondering if it's still really effectice? i dont want a vacum system. thanks for your opinions

[michiganfarmer]

vacuum is very expensive. I think that if you dont want vacuum, dont use it. I do recomend very strongly that you strech some high tensile wire, make sure it is tight, no droops, sloped, and hang your mailine on it. That will get all your sap down to your collection point. Sap wont be sitting in droops in the mains, and any sap or pressure the trees produce wont be wasted tryign to push sap up hil.

[WESTVIRGINIAMAPLER]

Works great for me as I have about 500 taps on gravity and have averaged 4500 to 5000 gallon of sap the last three seasons which isn't setting the world on fire, but almost half of my taps are small hillside trees that run only about 50 to 60 percent of a normal tap, so I have closer to 400 normal taps.

[PerryW]

I don't have vacuum and I get along fine. I know it would increase my production and I may do it sometime...., but I like to keeps things simple.

I think the problem with the natural vacuum is that...

While it definitely helps when the sap is already running, natural vacuum won't get the sap started flowing like a vacuum pump will. One these days without an overnite freeze, a vacuum pump will suck sap all day long.

I would like to try an experiment on by sugarbush with natural vacuum. About 60% of my 650 tap main sugarbush are at the top of a hill with about 200' of vertical rise. If I pipe together about 25 or 30 trees and run it straight down the hill to the tank (instead of into the mainline), I bet I could pull some serious vacuum (once they got running). Maybe I could use this technique with a much smaller vacuum pump which which just get things started and then the natural vacuum would take over.??

One thing I noticed when switching over to the Rigid 5/16" tubing was that I did NOT get as good natural vacuum as I did with the old smaller diameter 5/16 flexible tubing. I know it sounds counter-intuitive, but the smaller diameter lines would develop a column of sap which would create vacuum (as opposed to a larger diameter which the sap tended to run like rain in a gutter.)

When tapping a bush for Natural Vacuum, it seems like you need to get at least 10 taps to create the columns of sap which create the vacuum