Tap hole size

[Lyle]

Here's a question for those with more knowledge and experience than me. In other words , pretty much anyone. How much difference is there in sap yeild with different size tap holes. I use taps that require appx. 1/2" holes and I have used some homemade ones that use 3/8" holes. I didn't notice a significant difference between them and was toying with the idea of going smaller yet, maybe 1/4" to 5/16". If there isn't a big difference, I like the idea of a lesser injury to the tree.

[Dave Y]

Lyle,
a 5/16 hole will produce aproxamitely 80% of a 7/16 hole. How ever, a 5/16 hole will run aproxamtely 2weeks longer. so the sap yeild is about the same.