Frozen trees

[NoblesvilleIN]

On another thread Dr. Tim posted something along the line of "it will take a long time for the trees to thaw" in response to a post about the temperature in Ontario (many days of sub zero).

Question for Dr. Tim,

In central Indiana, it has been below freezing for the last 2 weeks (highs ranging from 5 to upper 20's) and its expected to continue for another week or so. I was planning on tapping a day or two before the forecast indicates above freezing temps. My thought is that by tapping a day or so before it warms up, I'll not miss the start of the run in what will probably be a short season. I think right now, the long range forecast indicates that Sunday, Feb 21st will have a high of 32*. My hope was that the sap would start flowing early that week. How long after it gets above freezing (figure highs in the mid-thirties to low forties) would yard trees thaw out enough to produce sap? I'm not looking for exactness, just an idea of what to expect.

Last year I tapped Feb. 5th and pulled Mar. 5th, when my wife said we had enough :) I'm tapping 6 sugar and 4 reds that I transplanted 30 years ago. Trees normally bud out by mid-March, so I'm thinking I'm not going to have much time to collect sap.

Thanks

[DrTimPerkins]

It is very difficult to say, although it is not at all uncommon for trees to take a few days to thaw out. We get a lot of questions in the early season about why trees aren't running. Tree temperature is buffered to some degree and won't react as quickly as air temperature....trees have an awful lot of moisture in them, so it's kind of like having a 12" column of solid ice that has to thaw out to some degree. Typically can take a day or two to thaw if the sun is shining. If it starts at 20 deg F, it'll take a good bit of time to reach the melting point. Then you've got the whole issue of aspect. South sides will thaw, but north side frozen quite a bit longer.

[NoblesvilleIN]

Thank you.

[Openwater]

Temp yesterday got up to mid 40's and my buckets were nearly empty. Thought I'd get something; was also mid 40's Monday with next to nothing. I'm getting a little nervous, but hoping it's taking a few days for the trees to thaw like you said.
Here's the local forecast for rest of the week:
22032
Hopefully today and the rest of the week produce some sap flow.

[NoblesvilleIN]

I tapped Saturday as planned. Sunday got up to maybe 35 and never dropped below freezing until last night. No sap Sunday, Sugars produced a little on Monday, nothing on Tuesday, and a little yesterday (Wednesday). I've run the little that I have collected thru the RO (RB-5) and froze it. I have less than 2 gallons of 8%. Last night got down to 25 and should get to low 40's today. I hope the trees have finally thawed enough to get a decent amount today. The reds have produced nothing yet. I only tap 10 trees and boil on a flat catering pan on my home-made smoker (so not very effecient). I hope to have enough to boil tomorrow. I try to boil 4 gallons of concentrate at a time.