sap flow conditions

[hholt]

This is only my second year tapping, so this may seem like a dumb question, but what are the ideal conditions for good sap flow. It seems like there's more to it than just below freezing at night and above freezing daytime temps. Sunny or cloudy? rising or falling barometer? still or windy? or is it just temperature. How high should day temps reach for ideal flow? How long can a "run" last?

[Russell Lampron]

The freeze thaw cycle is a reference to ideal conditions. You will find that the sap runs when it wants to sometimes. I have had good runs on windy days when the temp never got above 35. I have had good runs on rainy days and other times when the rain stopped the sap flow. I have also had ideal days and no sap flow. Sometimes the sap will flow for 3 days without stopping. The longer I am in this business the more I find that there is no such thing as a normal year.

Russ

[hholt]

Thanks Russel........I had something strange a couple of days ago. After checking nearly dry buckets for about a week we had a short cold snap then a storm with lots of rain and high winds. when the storm pased I had over a gallon of sap per tap. It wasn't really what I expected. I down in southern Illinois and I think that probably makes things even less predictable.

[VtSugarhouse]

I might try a sap barometer if I wanted to know when the sap was flowing. Only a thought. I use one just to watch the height of the sap.
You can install one cheap and easy yourself. Take a piece of sap tubing about 4 feet long with a spout at each end. Put one in the base of the tree about a foot off the ground and the other as high as the length of your tubing. Just watch it. When the sap increases in flow it goes up as the flow slows it goes down. This will flucuate in feet as well as inches.
I got this from the Canadians and they swear by them. I am just watching it for now. I can tell you when the sap in the line rises that the trees are running.
This is just food for thought and not a scientific method.

[TapME]

vtsugarhouse, I will have to try that.

[hholt]

I'm going to give that a try VT! I don't know a lot about the physiology of trees but it sure seems to make sense that something like that could work.