Checking what VT sugar makers are doing

[DrTimPerkins]

Decent run yesterday until a little after midnight. Another 1.2 gal/tap, so at about 82% of our minimum target crop in terms of sap. Sugar is starting to drop a bit - normal for this time of season. Down to 2.2 and 1.7 Brix in our two woods sections. Still a decent amount of snow in the woods, and no hot weather predicted for a while (58 deg F high on Saturday, but accompanied by a little rain which should keep the trees from getting real hot, and provide some soil moisture). Other than that good weather forecast for the next 10 days. Crew boiled yesterday and make 520 gal of syrup. Nice to see those barrels getting filled.

[Andy VT]

Dr Tim, when you say minimum crop of .5 gallons per tap... by this you mean a sort of breakeven point?

[Mooneybc]

Any thoughts or studies on tapping practices/sanitation affecting sugar content or do studies only show there is affect on sap yield? My guess is that sugar content is really out of the control of the producer?

[blissville maples]

Any thoughts or studies on tapping practices/sanitation affecting sugar content or do studies only show there is affect on sap yield? My guess is that sugar content is really out of the control of the producer?

Don't overdrive the spouts is your only way to help this, and possibly tapping later in the year

[blissville maples]

Wish we had some sugar in our sap, down to1.0. but making some great tasting almost Amber syrup. Next week will probably do it for us here in the lower elevations. We're currently at a .49 so that's good for our production. Hoping to see a .55

[blissville maples]

Decent run yesterday until a little after midnight. Another 1.2 gal/tap, so at about 82% of our minimum target crop in terms of sap. Sugar is starting to drop a bit - normal for this time of season. Down to 2.2 and 1.7 Brix in our two woods sections. Still a decent amount of snow in the woods, and no hot weather predicted for a while (58 deg F high on Saturday, but accompanied by a little rain which should keep the trees from getting real hot, and provide some soil moisture). Other than that good weather forecast for the next 10 days. Crew boiled yesterday and make 520 gal of syrup. Nice to see those barrels getting filled.

Why does the sugar drop? All the carbs are gone or the tress just don't convert as many carbs to sugar? Weather not cold enough?

[DrTimPerkins]

Why does the sugar drop? All the carbs are gone or the tress just don't convert as many carbs to sugar? Weather not cold enough?

It is a normal pattern. Sap sugar typically starts off fairly high, rises a little, then drops off as the season progresses. It can pop up a little after a good freeze. This is due to the physiology of the tree. https://mapleresearch.org/pub/mn2020sapsugar/

Most of the carbs in the wood rays are converted to and stored as starch, but as the spring gets close, a portion of that is converted to sucrose (more readily useable for tree metabolism) where it is important in providing some energy to fuel the growing tissues (roots, cambium, buds) and, to a slight degree, important in the sap flow process (although wood temperature is by far the larger driving factor in sap flow). Only a small portion of the starch gets converted, there is a lot left after the season is ended. Temperatures falling below freezing tend to push the enzymatic conversion of starch to sugar.

This isn't an abnormal thing in biology. If excess energy is made (or consumed), then a portion of the excess can get stored for later use. In people that's as fat -- in plants it is a starch. It may be converted later and get used, or may just hang around for a long time. The difference is that in trees the starches tend to be laid down within the rays of annual rings, but more can be added and some can be remobilized down the road as needed. Rays are the tissues that 1. are living and 2. cut across annual rings, so the mobility of the sugar is higher than many other compounds in the wood.

The sugar we collect by tapping comes from many annual rings of rays in the wood. In fact, the average age of the sugar molecules in maple syrup tends to be around 3 yrs, but ranges from less than 1 to 20-25 yrs. The hydraulic conductivity (the ability/rate/amount of sap to move through the stem) and carbohydrate levels tend to be highest in the outermost rings, then drop off as we get deeper. That's why drilling a taphole beyond a certain depth doesn't get us a lot more syrup yield. These reasons (higher sugar in the newest rings and higher hydraulic conductivity in newer rings) are why we've designed the barb spout https://mapleresearch.org/pub/innova...ystems-spouts/ currently being tested in several places in the U.S. and Canada. The new spout design allows better collection from shallower parts of the taphole and allows better collection during the frequent short thaw periods (when only the outermost portion of the wood thaws out) in which normal spouts do not run or run much.

At a certain point (decades), some amount of carbs are lost due to continued tree growth when the sapwood deep in the tree eventually converts to heartwood and is thus lost to the tree (and to sugarmakers).

Before the season starts, from the fall through the winter, the sap in xylem tends to be quite low in sugar (it's all being converted to starch and stored for future use). That's why when people try fall and early-winter tapping the sap tends to have very low sugar so syrup yields tend to be lower.

[DrTimPerkins]

Another 5,250 gal of sap yesterday. Sugar dropping a bit. Hard freeze overnight. RO is running. 700 gal of 33 Brix concentrate in the bulk tank, so probably boiling sometime within the next few days. Good sap flow weather forecast with a several nice freezes through the end of next week at least. Tally ho!

[DrTimPerkins]

Decent run yesterday afternoon/evening. Started late since the temps had dropped into the upper teens/low 20s overnight and it took some time for the trees to thaw, even with no wind and good sun. Collected about 7,300 gal of sap (about 1.1 gal sap/tap) running at 1.9 and 1.7 Brix in the two sections. Crew is running the new sap through the RO and boiling the 700+ gal of 33 Brix concentrate we had in the bulk tanks through the evaporator today. Still making GD syrup. Should be a total of just over 400 gal of syrup headed into the drums.

Sap surely isn't going to run for a few days (too cold).

[DrTimPerkins]

No sap today -- too cold. Crew made 480 gallons of GD...close to the line of AR. That puts us at 73.6% of our minimum target crop (0.5 gpt of syrup), not counting what we'd get in the boil out of the evaporator. Should run starting tomorrow afternoon thru early-Sunday morning, then freeze solid again most of Sunday until late-morning on Monday. Shaping up to be a couple of real gushers (fingers crossed).