Checking what VT sugar makers are doing

[DrTimPerkins]

Decent sap run yesterday and overnight, although it slowed down quite a bit with all the wind. Guessing at this point that once everything is boiled we'll be right at our typical average production (0.59 gal/tap). Sap was down around 1.6-1.7 Brix yesterday. Waiting for the sap tally from the crew, so no solid numbers yet.

I think we did get a freeze, at least in parts of our woods. At 7-8pm some of the Smartrek sensors started dropping below freezing in the colder sections of our woods, and the vacuum started to tighten up a bit...a good indication of a freeze (trees stop producing sap AND gases when it freezes, so vacuum goes up a bit). Vacuum started a slight drop this morning around 7am, so they're starting to thaw out.

Forecast looking like a solid freeze Tues night/Wed morning, so that'll help a lot. a couple of 50+ deg F days towards the end of the week, but nothing real hot and some occasional rain to keep the soil moist. Flow still seems good so far. We'll get at least another week out of it, perhaps more if we do get some decent freezes.

I happened to remember yesterday that the float box on the incoming concentrate line might not have been drained and asked Wade by text to check it next time he was around the sugarhouse. He sent me a video of it...was like slightly congealed gravy...very ropey (not surprising), but the rest of the pan is OK. He fired up for 5 min to kill anything else that might have started in the pan (since we only boil about once a week).

ropey.jpg

RO will be running a good bit today for sure. Won't have numbers until late this afternoon. The crew will be boiling tomorrow.

[spud]

Hey Dr. Tim what is the elevation to the areas of your woods that froze? My woods highest elevation is 1263. I thought yours was 1300-1650.

Spud

[tcross]

i'm at 1200 feet at my house and i got a freeze last night. certainly not a hard freeze. it was 32 at 8 p.m last night and 30-31 this a.m at 5. hope that kicks the trees into gear a bit as the flow was minimal yesterday.

[DrTimPerkins]

We have a really high density of Smartrek sensors, and the temperature precision and accuracy leaves a little to be desired, plus positioning of the units is not exceptionally uniform. We see a wide variation in temperature in the woods, probabably partly due to those factors, but also due to microclimate. Sometimes it is due to elevation (higher is sometimes colder, lower is sometimes colder). Often it is due to drainage (cold air follows the drainage patterns). Sometimes it is aspect (direction the woods faces) or when the sun was out during the day.

Keep in mind the sensors are in the woods at about 4-5 ft high. It is generally colder up in the tops of the trees 80-100 ft up. The fine branches can freeze, but the stem remains thawed. Still, there can be some amount of recharge when this happens. Not a full recharge, but enough to bump the sap flow up a bit the next day. Tim Wilmot did a lot of those types of measurements years ago. We are doing some of that now also, trying to get a better understanding of temperature and pressure/vacuum patterns in trees around a taphole under vacuum.

Capture1.jpg

The round blue things are vacuum sensors connected to small holes (via the yellow tubing) all around the stem -- they measure and record pressure/vacuum every 5 min. There are also temperature sensors in the tree measuring/recording temperature patterns at taphole depth all around the stem. This will allow us to produce a "map" of pressure/vacuum in the stem during water uptake and sap flow cycles, in a tree connected to a vacuum system. This is a student project. It is similar to a project Abby and I were doing several years ago that led to the "sapling capping" work.

The freeze we had yesterday happened in our more northwest facing woods, mostly higher up, but also in the drainage channels. Happened starting shortly after the front passed through in the evening. Was spotty, but covered (eventually) a majority of the woods.

[Sunday Rock Maple]

Like the picture and what it represents --- the search for fundamental understanding.

[DrTimPerkins]

Like the picture and what it represents --- the search for fundamental understanding.

Thank you. We understand a good deal, but always seeking to refine our knowledge.

[tcross]

the short freeze up certainly helped me today! have about 125 gallons in the tank, from my 330 taps, since 6 this a.m. sap sugar tested 1.8 for yesterdays boil... hope today's is similar.

[tcross]

is anyone experiencing an abnormally high concentration of nitre this year? mine is supper fine and a lot of it! i can only get through about 150 gallons of sap (non ro) before i need to shut down and swap pans. what a PITA! it is filtering easily and coming out crystal clear however. seems last few years i could do twice that before swapping pans.

[WestfordSugarworks]

How old is the tubing and especially the drops in these woods?

The tubing was installed fall 2015 and this is our 5th year tapping these trees that I mentioned where we are running CV2s. Drops are same age.

We also used non CVs in a different section of the same woods that was tapped on January 1 and these are still running just as well as CV2s from what I can tell. The mainline, lateral, and drops were installed summer 2018 and this is our second year tapping these trees. The spouts are made by leader and look like the CV2s but without the ball. I checked them today and they looked good.

One thing I did not mention about the CDL Signature spouts which have stopped flowing is that we've had at least a couple times where drops popped off of the spouts, created big leaks and frozen saddles. Sap then backs up the mainline, laterals, drops and pushes sap back up into the tap hole. So those tapholes have been exposed to more microbes than average if you compare to tapholes on other mainlines in the same woods where we are running CV2s.

[spud]

It was 29.9 degrees at my house this morning. I assume it was a bit cooler in the woods. All the woods froze but only for 4-6 hours. Today its supposed to be full sun and 46 degrees. If I don’t see a decent run then I know the end is very near. Sap dropped to 1.4% late yesterday. I woke up to 1000 in the tank. I had emptied the tank last night at 5:30pm.

Spud