Vacuum for sugar testing?

[Beweller]

I have been frustrated trying to get sap samples for sugar testing in the fall. No sap, even if the weather looked favorable, or sap from only a couple of trees.

Has any one tried vacuum augmentation to obtain out-of-season sap samples?

Using micro-taps and battery or hand operated vacuum pumps?

[Haynes Forest Products]

My wife has a pump that didnt work out for her you could do 2 trees at the same time. Small conversion needed........................................Dont even say it Ken

[KenWP]

Hard to pump up something that dosn't work.
I have to drill a tree one of these days and see if I can get sap in the fall.

[3rdgen.maple]

Beweller are you trying to get sap right now??? If so its to soon. You still need freezing nights and warm days for it to run.

[DrTimPerkins]

Beweller are you trying to get sap right now??? If so its to soon. You still need freezing nights and warm days for it to run.

Correct. Sap won't flow until we get some below freezing temperatures.

The other thing....don't compare sap sugar content from fall and winter. They will be very different even from the same tree. At this time of year trees are actively converting sugar produced by the leaves into starches to be stored in the wood. Sap sugar content changes in response to lots of things.

[Beweller]

Notice I said "augment". Please read the entire post.

Season in SE Ohio--Feb-Mar, maybe late Jan. Period of interest Dec-early Jan, maybe late Nov. Same period people think of when talking about fall sugaring.

I gather no one has tried.

[DrTimPerkins]

Notice I said "augment". Please read the entire post.

Season in SE Ohio--Feb-Mar, maybe late Jan. Period of interest Dec-early Jan, maybe late Nov. Same period people think of when talking about fall sugaring.
.

It is hard to tell exactly what you're after, but if your question is, what is the seasonal course of sap sugar content?, then there have been lots of research studies looking at this, and lots of sugarmakers have collected fall sap as well.

Going back to your original question, can you pull sap from trees with a vacuum when it isn't running naturally -- yes, you can pull sap from maple trees with vacuum any time of year (unless it is frozen), even if they have leaves on them. However sap chemistry in the summer is very much different from what it is after the leaves fall off, and sap chemistry in the winter and spring are different than in the rest of the year.

If you drill a hole with leaves on the tree (or for a period of time afterward) and do get sap dribbling out without using vacuum, it is probably mostly phloem sap (with foliage on the tree, the xylem in the stem is under negative tension -- a slight vacuum -- so sap will not run out, and instead air will be sucked in). Phloem sap comes from what most people would call the "inner bark", is very high in sugar, and is under slight pressure (so it'll dribble out) in the summer and early fall. If no sap comes out of the taphole (and it is above freezing) in the summer or early fall, so you put vacuum to the taphole to try to get some, you'll likely end up collecting a mixture of both xylem sap and phloem sap. So in the summer and fall, there is contribution of phloem sap to the xylem sap, which renders the sap chemistry not all at indicative of what spring sap would be. In the spring, all the sap comes from the xylem...none from the phloem.

[3rdgen.maple]

Notice I said "augment". Please read the entire post.

Season in SE Ohio--Feb-Mar, maybe late Jan. Period of interest Dec-early Jan, maybe late Nov. Same period people think of when talking about fall sugaring.

I gather no one has tried.

Sorry but I did read the entire post a few times. It is just unclear as to what you are trying to achieve, well atleast for me. Hence the reason I asked if you are trying to get sap now. Reason I asked that is basically what Dr. Tim is saying. The sap you are trying to get with leaves on the trees is not the sap you will get when they are gone.

[Beweller]

I hand not realized that knowledge and understanding of sugar testing for evaluating maple trees was so uncommon. The process is described in the current maple handbook as well as in the 1996 handbook (OSU Bull 856) and the 1958 handbook (Ag hdbk 134). These older handbooks are available on the web.

A substantial discussion of how and when sugar bearing sap flow occurs can be found in USDA NE-72, also available on the web.

A refinement I have attempted (conclusion still out) is to always incorporate a small group of specific trees as "reference trees". The average sugar content of these trees is used to normalize the sugar content of all other trees measured in the same campaign. The normalized values are then combined for different campaigns, even those in different years.

[Flat Lander Sugaring]

I hand not realized that knowledge and understanding of sugar testing for evaluating maple trees was so uncommon. The process is described in the current maple handbook as well as in the 1996 handbook (OSU Bull 856) and the 1958 handbook (Ag hdbk 134). These older handbooks are available on the web.

A substantial discussion of how and when sugar bearing sap flow occurs can be found in USDA NE-72, also available on the web.

A refinement I have attempted (conclusion still out) is to always incorporate a small group of specific trees as "reference trees". The average sugar content of these trees is used to normalize the sugar content of all other trees measured in the same campaign. The normalized values are then combined for different campaigns, even those in different years.

yeaaaaaaa what they both said:confused::lol:

[wiam]

I hand not realized that knowledge and understanding of sugar testing for evaluating maple trees was so uncommon. The process is described in the current maple handbook as well as in the 1996 handbook (OSU Bull 856) and the 1958 handbook (Ag hdbk 134). These older handbooks are available on the web.

A substantial discussion of how and when sugar bearing sap flow occurs can be found in USDA NE-72, also available on the web.

A refinement I have attempted (conclusion still out) is to always incorporate a small group of specific trees as "reference trees". The average sugar content of these trees is used to normalize the sugar content of all other trees measured in the same campaign. The normalized values are then combined for different campaigns, even those in different years.

I have not figured out what you are trying to accomplish. Is this for thinning?

Do you know what Tim Perkins does??

[Beweller]

Wiam, Are you asking for information regarding forestry? If at the beginning level I would recommend Ecology and Management of Central Hardwood Forests[U], Hicks, Wiley and Sons, 1998. At the advanced level I might suggest [U]Forest Stand Dynamics. Oliver and Larson, John Wiley and Sons, 1996. There are probably more recent sources, and there are a vast number of sites on the web.

Do I know what Tim Perkins does? I have the impression that he is employed by UVM, but I have no knowledge of his employment contract nor have I ever seen his time log.

A friend brought the first of his four children to work to "see what Daddy does". He reported that when he and Nr 1 child arrived home, the other three where waiting: "What does Daddy do?" Answer, "He doesn't do anything!" He was an associate director. Our employer published a set of job titles and functions. Consulting these, he concluded that he was a "Receptionist B", whose duties were to "Accept incoming phone calls and direct them to the proper person."

[Beweller]

In the references to sugar testing, "Variation in Sugar Content of Maple Sap", FW Taylor, UVM Bull 587, must be included.

[3rdgen.maple]

Ahhhhhhh yeah I completely follow your post, well okay maybe not.

[Cake O' Maple]

Wiam, Are you asking for information regarding forestry? If at the beginning level I would recommend Ecology and Management of Central Hardwood Forests[U], Hicks, Wiley and Sons, 1998. At the advanced level I might suggest [U]Forest Stand Dynamics. Oliver and Larson, John Wiley and Sons, 1996. There are probably more recent sources, and there are a vast number of sites on the web.

Do I know what Tim Perkins does? I have the impression that he is employed by UVM, but I have no knowledge of his employment contract nor have I ever seen his time log.

A friend brought the first of his four children to work to "see what Daddy does". He reported that when he and Nr 1 child arrived home, the other three where waiting: "What does Daddy do?" Answer, "He doesn't do anything!" He was an associate director. Our employer published a set of job titles and functions. Consulting these, he concluded that he was a "Receptionist B", whose duties were to "Accept incoming phone calls and direct them to the proper person."

So you are being deliberately obtuse? :confused:

[Brent]

I'm scratching my head about where this thread is going.

Anyway, if there was good sap to be collected in the fall, most of us here and our predecessors would have been doing in large numbers for generations. You can get some, occasionally, but it's generally considered not worth the effort.

So I doubt you'd get much that would be worth testing that would give you a good indication of what a tree would yeild in the spring.

2 cents please

[Beweller]

Again, fall sampling for comparing the sugar concentration of various trees is discussed in various editions of the maple producers handbook.