Most spiles require either a 7/16 or 5/16 bit. Drill a hole 2 to 2 ½ inches deep. It may be helpful to wrap a piece of tape around the drill bit 2 ½ inches from the tip to use as a guide. Drill at a slight upward angle to facilitate downward flow of sap from the hole.
For example the 2nd Edition of the North American Maple Syrup Producers Manual (2006) suggests that tapping depth be no more than 2” below the bark. Additionally, many organizations that certify maple as organic restrict tapping depth.
The general rule of thumb is that it takes 40 parts maple sap to produce 1 part maple syrup. This translates into 40 gallons of sap to produce 1 gallon or syrup (or 10 gallons of sap for one quart of syrup). This estimate is dependent on the sugar content of your sap.
How Long Can You Leave A Tap In a Maple Tree? A tap should stay in the maple the entire sap season, about 4-5 weeks long. Above-freezing days followed by below-freezing nights are the best conditions for sap flow. This usually happens in February and ends in mid-March.
When you tap a tree in the spring, it is the equivalent to a human getting a small cut, which will will slowly scar over to stop the loss of bodily fluids. Hence, if you tap too early, the “scarring” will gradually reduce the flow of sap over the spring.
Use a sharp, clean drill. Drill a hole that's 2” to 2.5” deep. Remove the spout at the end of the season so that your tree can begin to seal the wound. If you tap the same tree each year, drill holes at least 6” apart from previous holes.
Maple syrup can be made from any species of maple tree. Trees that can be tapped include: sugar, black, red and silver maple and box elder trees. Of all the maples, the highest concentration of sugar is found in the sap of the sugar maple. … Other species of maple have lower concentrations of sugar in their sap.
But just as an FYI – 5 gallons of sap usually end up resulting in approximately 16oz maple syrup. If you tap one sugar maple tree you will normally get about 10-20 gallons of sap in a season.