In reply to your correspondent's queries I would say: Yes, there is always sap in the trees, but certain conditions are necessary to make it flow. The principal requisites are freezing and thawing, but a good " run " of sap must be the result of a combination of favorable circumstances. The best runs occur when, immediately after a snow storm, or a rain which is followed by a freeze, we have warm weather with wind southwest or northeast; and it often runs pretty freely with wind northwest or east, but never with wind south; and if any considerable time intervened between the storm and thawing weather, especially if accompanied by drying winds, we rarely get much sap - almost the only exceptions being when very damp southwest or northeast winds accompany the thawing out. Now if we have cold dry winds for several days after each storm, or if nearly all the thawing is done by south winds, there will be very little sugar made. It seems to make very little difference whether winter sets in with the ground frozen deeply or snow covers it with no frost in.

I have known very good and very poor sugar seasons to follow either.