Vacuum Style and Spout Selection

[GeneralStark]

It seems there are many different "styles" of vacuum use from waiting until the sap starts to run to turn the pump on to leaving the pump on all season 24/7. There are also many different spout options from check valves to stainless steel. There are also different styles of releasers and different ways to plumb your system. Clearly there are advantages and disadvantages to each vacuum method and spout option. If using a gas powered vac. pump it may be too cost prohibitive to run the pump 24/7. If using an electric pump, it may make sense to just let it run all season.

This season was a major game changer for me. I bought a new woods and set it up for high vac. with an over sized pump and a DIY electric releaser with submersible pump. The system worked flawlessly and production was good despite challenging weather. Never again will I use a mechanical releaser and never again will I turn the pump on when the sap starts running and turn it off when it freezes up. Instead, I will keep the pump running all season as I did this year. The reasons to do so have become so clear to me.

That said, I find myself looking to next season and planning how to make improvements. I have been using CDL Smart Spouts and changing drops every 2 years up to this point. I am starting to consider using CV2s on tubing more than one season old, but I'm not sure it is really worth it in my situation. When using an electric releaser and keeping the pump on 24/7 is the check valve spout really necessary? I realize the studies show a clear advantage to the CV spout, but do these studies represent all the possible variables?

Any thoughts? Opinions?

[Maple Hill]

If you run your vac pump 24/7 you do not need to use cv 1 or 2 but should still change the spout every year.

[DrTimPerkins]

If you run your vac pump 24/7 you do not need to use cv 1 or 2 but should still change the spout every year.

There is no scientific evidence available to either confirm or dispute this, except perhaps for one study done by Centre Acer where electric releasers were used. In that work they found that CV1 did have a significant increase in production at one of their sites, but did not have any effect at the other site (although at the second site their production was so incredibly low that something else must have been going on). In our studies at UVM PMRC with the CV1 and CV2 spouts, since the second year, we have always kept the pump running at all times throughout the season. They are turned on during or shortly after tapping, and turned off when spouts are pulled. In one year the pumps did stop because the power went out (transformer problem at the pole). We do use mechanical releasers however. Given the fact that we have 32 different releasers (due to the need to keep sap separate so we can measure the sap volume in our studies....most of these are small-custom made releasers), it would not be possible to use electric releasers due to the prohibitive cost and complexity. We do plan on changing at least some releasers for next season to the "continuous" vacuum-style of releasers to see whether it makes a difference. My personal feeling is that using an electric releaser might help to some degree, but will not totally eliminate the problems that the CV spouts are designed to deal with.

[Mark]

There is no scientific evidence available to either confirm or dispute this, except perhaps for one study done by Centre Acer where electric releasers were used. In that work they found that CV1 did have a significant increase in production at one of their sites, but did not have any effect at the other site (although at the second site their production was so incredibly low that something else must have been going on). In our studies at UVM PMRC with the CV1 and CV2 spouts, since the second year, we have always kept the pump running at all times throughout the season. They are turned on during or shortly after tapping, and turned off when spouts are pulled. In one year the pumps did stop because the power went out (transformer problem at the pole). We do use mechanical releasers however. Given the fact that we have 32 different releasers (due to the need to keep sap separate so we can measure the sap volume in our studies....most of these are small-custom made releasers), it would not be possible to use electric releasers due to the prohibitive cost and complexity. We do plan on changing at least some releasers for next season to the "continuous" vacuum-style of releasers to see whether it makes a difference. My personal feeling is that using an electric releaser might help to some degree, but will not totally eliminate the problems that the CV spouts are designed to deal with.

I have an electric releaser and it is kept on all the time. We also have the Smartrek monitoring system on some lines and have discovered there is much more going on it the bush than I would have expected. You would be surprised to find out how often some lines freeze up early and vacuum is lost before the trees are frozen. Sometimes you can find the cause and other times not. If you think keeping the vacuum on all the time will keep the tree from pulling back you would have to be lucky.

Also we have been trying the check valves since they came out. I don't know what we are doing wrong but we are not seeing any difference. I am sure they work but wished we would see it. We have three of our lines that run about the same all the time and have the same number of taps. This year we put the cv2's on one of those sections. We watched it every day and expected to see it perform better in the second half of the season but could not see a visual difference. I know that is unscientific but that is about all I can do. They quit at the same time as the other old tubing. We have another area with new tubing and we just turned off the vacuum yesterday on May 5th. We had been making syrup off the new stuff that went a good week longer. We just put the non check adapters on those for the first year since the tubing was new.

Maybe we are not cleaning to tubing correct or something else. At Proctor do you tap with vacuum on to keep anything in the tubing away from tap right at the start? What do you do when you pull the taps, vacuum on or any type of cleaning?

[sjdoyon]

We use the original CVs with the stubby. Last boil this year was on the 1st of May, pulling spouts this week and sap is still running at our higher elevation trees. It seems like every sugarbush is different in some way so difficult to judge which spout is better but there is research out there to help you out. Definitely keep your pump on, we turn it on at the beginning of the season and only turn equipment off for maintenance until the end of the season.

[eagle lake sugar]

My trees are still running now, as I'm pulling taps May 8th. They're on clear seasonal spouts. The sap, however is cloudy and nasty. My question is, do the c.v.'s increase production during the season, or only extend the season? I want to try some next year, but extending the season is of no value to me after the sap becomes cloudy and buddy.

[DrTimPerkins]

My question is, do the c.v.'s increase production during the season, or only extend the season?

Actually they do both. The effect begins in about mid-season and builds through to the end.

[eagle lake sugar]

Actually they do both. The effect begins in about mid-season and builds through to the end.

Thanks doc., I think I'll try some next season on a new wet/dry system. I should be able to tell if there's a difference in production between the two systems.

[DrTimPerkins]

I think I'll try some next season on a new wet/dry system.

If the system is totally new (new lateral and droplines with new spouts), or if you change all drops one year (new droplines and new spouts) for some reason or other, then the use of CV spouts is not necessary. You might see a small benefit, especially in an extended season, but it will be fairly modest at best. I'd go with any other standard spout in Year 1, then switch to CV spouts for subsequent years. As the drops age, the benefit increases.

[knsh]

Has anyone had any experience with ZAP-BAC antimicrobial (silver) spouts. We are considering buying them but can't find much information either from the manufacturer or from folks who have used them.

KNSH, Shrewsbury, VT

[DrTimPerkins]

Has anyone had any experience with ZAP-BAC antimicrobial (silver) spouts. We are considering buying them but can't find much information either from the manufacturer or from folks who have used them.

Steve Childs of Cornell has done some research on them. We found antimicrobial silver to drop in efficacy after a season or two, but it was not with this exact product. They are not allowed in organic maple production.