3/16" drops vs 5/16" drops

[Bullet]

I have 3/16" mainline. I've used 3/16" drops into this mainline. I've heard/read that you would get higher sap flow and decrease bacteria if you go to 5/16" drops into 3/16" mainline. Comments and advice appreciated.

[maple flats]

While it's not the "mainline" , I use 5/16 drops into my 3/16 lateral lines, the reason is because as the temperatures fall to below freezing at night, the sap in the drop will not be pulled back into the taphole. In 5/16 tubing any gases will pass the sap and the sap stays out of the tree. What sap is in the tree, if the tree is healthy, is sterile once it hits the tubing it get bacteria in the sap, thus I use the larger tubing for drops. If I used 3/16 drops, the gases would not pass the sap and as the tree freezes it would pull some bacteria back into the tree, thus starting a wound response in the tree, initiating the wound response starts the tree healing.

[DMF]

I use 3/16 lines and 5/16 for the drops as well for the same reasons Maple Flats mentioned above.

[DRoseum]

Yep it essentially achieves same result as using CV spouts. One benefit of CVs over the 5/16th drop is ability to tap below the lateral line and still prevent the backflow into the taphole.