I respectfully disagree. With no slope, you have issues with 5/16 laterals. They need slope at least on the tubing even if the woods has none. Then if going very far, you need sap ladders to lift the sap in the main to a higher level then you can continue down a slope again.
I ran 3 lines in my flat woods this year using 3/16 as an experiment. I have 1 that is fairly flat and 2 that are actually lower away from the main than they are at the main. I have 25" vacuum on the main, which some vacuum is necessary for this method to work. If I remember, one line has 7 taps and I think the other 2 lines have 9. With the vacuum running those 3/16 lines move quite impressively, however the line friction and negative slope of the 2 that are lower than the main will reduce the vacuum, but the sap continues to move to the main. At the end of the main where the 3 test lines are has 22-23" vacuum after 2 sap ladders and a needle valve micro leak at the farthest out ladder about 40' before the ladder.
To do this you must have a vacuum pump, either a maple pump, an old dairy pump or a diaphragm pump (the last one is least cost to set up and requires no releaser, any conventional vacuum pump must have a releaser or you need a vacuum tank (a tank built to hold up to vacuum or it will implode, and then you need to know what vacuum level is safe with that tank).
If you have electric available on a diaphragm pump use that, if not, use a 12V and get 2 good deep cycle batteries, one to use while thew other charges. An AC plug in one is far simpler to run but do what you need to.
Dave Klish, I recently ordered a 2x6 wood fired evaporator from A&A Sheet Metal which I will be converting to oil fired
Now have solar, 2x6 finish pan, 5 bank 7x7 filter press, large water jacketed bottler, and tankless water heater.
Recently bought another Gingerich RO, this one was a 125, but a second membrane was added thus is a 250, like I had.
After running a 2x3, a 2x6, 3x8 tapping from 79 taps up to 1320 all woodfired, now I'm going to a 2x6 oil fired and a 200-425 taps.