New publications

[DrTimPerkins]

New publications posted to the UVM Proctor Maple Research Center page at http://www.uvm.edu/~pmrc Look over on the right side, under the "Recent Publications" heading.

[happy thoughts]

Thanks Dr Tim! :) Interesting pubs as always. I liked the rework of the Jones Rule and hope to get around to reading a few more. That said, there is a link in the "publication Spotlight" for a PDF called "Maple Syrup - Production, Composition, Chemistry, and Sensory Characteristics. pp. 102-144." PDF Only contains the first 2 pages of the chapter (pp 101-102). Was that intentional just to give a taste of the contents of the chapter or is the complete chapter available somewhere else online?

[DrTimPerkins]

...there is a link in the "publication Spotlight" for a PDF called "Maple Syrup - Production, Composition, Chemistry, and Sensory Characteristics. pp. 102-144." PDF Only contains the first 2 pages of the chapter (pp 101-102). Was that intentional just to give a taste of the contents of the chapter or is the complete chapter available somewhere else online?

Unfortunately the complete version of that paper is not available for free online. It is much more of a scientific paper, and the publisher would like to recoup some of their investment back on it I guess. We aren't allowed to distribute the full copy, but it is probably available in most University or research libraries though.

[happy thoughts]

Thanks Dr Tim. That's understandable. I had a feeling that might be the case but thought it worth asking. Thanks again for the links :)

[DrTimPerkins]

Two new additions to the University of Vermont Proctor Maple Research Center "Recent Publications" (over on the right). http://www.uvm.edu/~pmrc/

· A Model of the Tapping Zone (pdf)
· Tapping Zone Model v10.15.13 (Excel)

This paper and the Excel model that accompany it are part of a multi-part scientific reassessment of the maple tapping guidelines. We welcome feedback and questions.

[spud]

Thanks Dr. Tim,

I look forward to reading this tomorrow if I feel better. I have had the Mongolian Death Flu for the last 4-5 day's but I think I am going to make it.:)

Spud

[SeanD]

This is interesting and it's something I think about when I'm tapping. I've only been doing this for a relatively short period of time and already some of the old tap holes are impossible to find. I know I'm going to hit brown wood sooner or later.

I couldn't get the model to work for me. When I enter data in the blue section, nothing happens in the % field or the graph. It says #NAME?

One of the things I was curious about is what happens to the Conductive Wood % when the tree gets to 18"-20" and it's likely to get a second tap. I know it's going to drop, but I wonder how much.

I was also curious if the recommended practice is to tap all the way around the tree. I had heard once not to do that, but I'll go with whatever the experts say.

Thanks,
Sean

[unc23win]

Try downloading it again and leave it as it is then change the number of taps and or the number of years and see if it works. Some of the fields the number has to change a lot for instance just a quick one for you 20" tree with 2 taps doesn't drop until 23 years of tapping using all the set numbers for tap size and depth. Maybe you didn't enter numbers that caused changes.

Most recommendations are to tap in a spiral like a stair case each year moving up and over from the previous year (avoiding previous tap hole by 6 inches in all directions) multiple taps would be multiple spirals. Different length drops help.

Thank you PMRC and Dr. Tim for sharing it is pretty cool.

[spud]

Dr Tim,

You know I am a big fan of PMRC and I don't question your work. I have no reason to think that the information giving on these charts is anything but spot on. In saying this though I still can't help to think that tapping a small maple (let's say 6 inch) is still very useful. The charts indicate that a 6 inch tree will only have 90% of it's conductive tapping zone left at about 12 years. Although a 12 inch tree drops at close to the same rate. If a tree in good soil grows 1/2 inch per year then it would take a 6 inch tree 12 years to become a 12 inch tree. If a person chooses to not tap that tree for 12 more years you could stand to loose 20 gallons of sap per year. If the sap was only going to test at 1.5% because it is a smaller tree then you still would have lost 4.1 gallons of syrup per tree. At a bulk price of $31.50 you than would lose $129.15 from each untapped tree. If a person sat around for 12 years waiting on his trees to grow before he tapped his 2000 tap woods then he would have lost 8000 Gallons of syrup=$252,000 In sugaring there are two different types of sugar maker's even though we all share the same passion for sugaring. The first type is the Money Maker who looks at sugaring as all business and needs to make the money now (not 12 years from now). The second type is the Tree hugging sugar maker who looks out for the best interest of his tree's (I commend these people even though I am not one of them). I am not trying to kill my trees but I do have a few thousand smaller trees that I tap in my woods. I try to be careful with tap hole depth on a smaller tree (but I'm tapping it just the same. I really don't see real advantages on not tapping smaller trees and I know I'm not alone. If you look at all the dealer's catalogs they have photos of trees that are tapped very small (maybe smaller then 6 inches) What I am (not) saying is that it is a good healthy thing to tap small tree's. I know I could be putting 2000 of my trees at risk of death but the pro's seem to outweigh the con's. If all 2000 trees die 12 years from now I can at least say I made $252,000 from them before they died. Also in the next 12 years I might have 2000 more young trees just reaching the 6 inch range. At that time I will let my kid's decide what they want to do with those trees. I'm just living the dream Doc.:)

Spud

[GeneralStark]

Spud,

I too tap smaller trees (less tan 10"), but only if I am going to thin them out in the near future. There certainly are potential issues with long term tree health when tapping small stressed trees, but when they are in the understory of a healthy sugarbush they probably won't be growing too quick anyway. I recently cut a small maple in my new woods that was 6" in diameter and was over 60 years old. The tree was so stunted due to being in the understory. This would never be a crop tree in my woods.

I personally prefer to wait to tap any crop tree until 10", but I do some aggressive thinning and may trees that are close to 10" will be there in a few years.

We all have different standards, and it is easy to see things in terms of how they affect us, but one thing to consider regarding tapping small stressed trees is potential for disease and invasive pests in your woods. If my sugarbush neighbored yours I would be concerned that your woods may become a vector for any of the many disease and pest issues that are here or are coming our way. These things seek out weak, stressed trees, and if you have many of these in your woods due to overtapping, your woods may be a logical spot for them to infest.

I know we have been through this before here, but I think your estimations of 20 g/tap sap from a 6" tree are pretty high, even with high vacuum.

[spud]

Thanks for the info General. The smaller trees I tap are nowhere close to being 60 years old. These small trees are young and strong with good growth rate (for now). There is a section of my woods that has 110 taps per acre and that is where I tap 2000 smaller trees. That section of woods needs a good thinning bringing it back to 80 taps an acre or so. I am not able to thin my woods at this time. Your 60 year old tree in poor health would never give 20 GPT. Although a healthy 6-8 inch tree does give that much and more. I base that information on PMRC and others on Trader that get those numbers. Proctor used 7 inch trees in a study and got over 30 gallon per tap on some. One of our Trader friends (Joe) from Essex Vermont gets 27-35 GPT and has for 6-7 years in a row. What I expect to see happen with some of my smaller trees is a decline in production. Maybe 25 gallons now and 15 gallons in 12 years (just a thought no research to back it). If thats the case I would have a 20 gallon average over the corse of 12 years. If I happened to notice any disease forming in my trees I would have to change my game plan a bit. Although I would never want to cause tree health issues for my neighbor's I think they are tapping real small tree's. Twenty years from now we may all be looking at a bare mountain.

Spud

[DrTimPerkins]

Spud (and all). The Tapping Zone Model is a tool to help producers estimate the impact of tapping on compartmentalization on their trees. It obviously cannot cover all conditions. It could certainly be improved IF we had the growth rate of trees in your bush (and future versions or future tapping guidelines might incorporate this). This model is based upon the average growth rates of a large number of healthy trees from across Vermont that have been tapped for high vacuum production for several years. Your mileage may vary depending upon your soils and thinning practices as well as many other factors. It is a tool to help you make decisions of whether your practices are likely to be sustainable (or not) over the long-term. It is up to the individual producer to decide what their individual objectives are, and to base your management on those objectives and the consequences. We're simply trying to provide some information producers might find useful in their decision-making process, and aren't making any judgments on what you ultimately decided to do with your own trees.

All that said, the tapping guidelines we use at UVM PMRC are minimum dbh of 10". Generally we go with 1 tap per tree, but in the past couple of years we've added a 2nd tap to some of the larger trees IF they are healthy. In a limited number of studies we've tapped smaller trees, but it is not part of our normal practice. Typically when we have tapped smaller trees it is primarily because we will be cutting them down to look at the internal staining caused by tapping. Because we're cutting them down we don't want to use large trees (more difficult, and would quickly deplete our sugarbush of tappable trees).

[unc23win]

Ok so I sometimes like to color outside the lines and I um typed in my own numbers say outside the parameters set under inputs and I noticed that the Proportion%and the Graph both seem to work. Just wondering is it working correct still Dr. Perkins? Or are the numbers off maybe some? I know that from what you said the tool was set up based on trees within the input parameters ( I will admit I haven't read the document).

I understand where Spud is coming from he makes very good sense when it comes to $ and I would never judge others practices and I find Spuds questions interesting. In additon to that I was wondering about the tool working the other way say more than 2 taps. When I type in 3 it seems to be calculating. So the same question as above applies here.

I think it is very interesting and useful tool maybe some of us might have tapping practices a little out of the parameters, yet still not be causing the tree stress or damage. Not to mention the fact that from what I have seen messing with the tool some we can keep the tree huggers happy as from what I have seen things have to be pretty extreme for the proportion % to drop a lot.

Once again thanks.

[DrTimPerkins]

Finding the Sweet Spot: Tapping Guidelines for Modern Sap Collection Practices

Dr. Abby van den Berg
Proctor Maple Research Center
University of Vermont

Wednesday, November 13, 2013
10:00—11:00 am
RSVP REQUIRED robin.orr@uvm.edu

Maple syrup production is a traditional practice in the Northern For-est that generates jobs, provides income, and maintains the tradition-al working landscape. Its long-term viability depends on the sustaina-bility of annual sap extraction which must not damage more wood than can be replaced by annual tree growth or extract enough sugar resources to reduce growth rates and hinder replenishment of func-tional wood.To meet these requirements, maple producers follow traditional "tapping guidelines." Today, however, modern sap collec-tion equipment and practices extract at least twice the volume of sap per tree than was possible with the technology used when the guide-lines were developed, and evidence suggests even greater extraction rates are possible.
Researchers measured annual growth rates of trees subjected to high-yield collection methods at 18 Vermont maple operations and devel-oped a model that estimates availability of functional wood in the tapping zone of a tree over time. They used the model to determine minimum growth rates required for tapping trees to be sustainable using current tapping guidelines.

[DrTimPerkins]

Ok so I sometimes like to color outside the lines and I um typed in my own numbers say outside the parameters set under inputs and I noticed that the Proportion%and the Graph both seem to work. Just wondering is it working correct still Dr. Perkins? Or are the numbers off maybe some?

1. It would probably be a good idea to read the accompanying information.
2. Although you might get results, we make no claims and accept no responsibility for validity of results outside the specified input parameter ranges.

[unc23win]

Thanks Dr. Perkins I will READ it tomorrow at work. To me it is a very useful tool. I find it interesting how things change when you change drop lengths and such. Seems to me from what I have seen by messing with the numbers one would have to be really overtapping a lot to get the proportion % to drop considerable. Just for me I have quite a few trees that I do 3 taps currently. Sort of the opposite end of Spuds questions.

I think that the tool makes that most often asked yuppie question Does tapping hurt the trees? more easier to answer.

[spud]

What would go great with this chart is a diagram showing best location to tap your tree from year 1-10 or so. Should there be a height difference every year or should the first four years just circle the tree at the same height? What is the highest someone should tap and why? In the spring when pulling taps I sometimes have a spout at the 7 foot mark (is that even good or should it be much lower). What is the sugar difference of the sap from a high tap hole verse a low tap hole. I think this would be very helpful for all sugar maker's and certainly very helpful for those who choose to tap smaller trees. If a person is tapping 8 inch trees there needs to be a real tapping plan put in place to make sure the tree does not fall over. I am sure Dr. Tim and other's could be of great help in this area.

Spud

[Scribner's Mountain Maple]

Spud,

I also tap some small trees and see value in the research you are talking about. I try to follow the best practices for tapping so I only tap these smaller trees, 6-10" dbh about 1 to 1 1/4" deep. I think this still gets to the sap and is not too deep as to hurt the tree real bad. I have alternated sides and height the following years thinking the tree is growing fast and this will make finding good wood easier down the road.

I understand the concern with tapping smaller trees, but haven't seen it in my woods. Have sugarmakers experienced large die offs of maples as a result of tapping trees before they reach 10"
dbh? And if so, was this using 5/16 taps, or 7/16? I imagine an 8" tree couldn't handle many 2" deep 7/16 holes. But 1-1 1/4" deep 5/16 holes are much less invasive. I wonder how many people have noticed young tree die off using only one 5/16 tap. Maybe we could learn that you can tap these trees every other year from 5-10" dbh and not impact the trees long term growth and production rates. Or even tap them every year if done a certain way. This is stuff I am interested in learning now as I too have lots of small maples sitting right next to an existing line. Has anyone done this type of research before? Determining how to sustainably tap maples less than 10" dbh for maple production?

Thanks.

Ben

[DrTimPerkins]

What would go great with this chart is a diagram showing best location to tap your tree from year 1-10 or so.

We do not advocate using any particular pattern, but rather to spread the taphole around (while avoiding obvious old taphole scars still visible) while utilizing the full tapping band of the tree. So in a low snow year, tap a little low. Deep snow, tap higher. Spread it around the circumference as well while ranging up and down. Definitely do NOT tap near an old taphole, as you might pull air through the old taphole.

As long as you do this, and your percentage of sound white wood is high (>=90%) then you shouldn't have any problems.

[DrTimPerkins]

I also tap some small trees and see value in the research you are talking about.

Like all things maple it seems, your mileage will vary. There are two possible issues (other than sap yield) to be concerned with.

1. Maintaining an adequate amount of sound tappable wood. Growth rates in young trees with an intermediate or suppressed canopy position can be quite low. Under low growth conditions, the amount of tappable wood will decline sharply over about 20-30 yrs time, with the result that over time yields will also decline as you create a situation where most of the interior of the tree is compartmentalized. Unless the tree has some canopy exposure to the sun, growth rates are apt to be low, and eventually you'll end up with very low sap yields from such trees.

2. Carbohydrate reserves in such trees are also low. These trees are often skating along the edge of survival on the "carbon curve" -- essentially they are on a near starvation diet. For plants the general rule is they need to capture enough energy through photosynthesis for maintenance and growth.....or else die. They need to make enough sugar to both maintain physiological functioning and to grow. Sap collection removes a much higher proportion of a small understory tree's carbon reserves than it does for a tree with a dominant or co-dominant canopy position. The result is that they will grow more slowly....and if the stress is prolonged, they will die. This is similar to the thinning process that occurs in a forest naturally.

IF you do decide to tap small trees, and you want them to thrive and produce sap for you for a long time (as opposed to "thinning with a tapping bit"), it is important that they have an adequate exposure of the crowns to sunlight.

Please don't misconstrue this to mean that I think tapping small trees is always OK......it really depends upon the circumstances, as well as the objectives of the producer, and their tolerance for losing some amount of young trees over a period of time. While we may not be able to definitively say that tapping of small trees is always bad.....there are certainly times when tapping small trees is definitely not good.

[spud]

Ben,

What I do know is that smaller trees (7") have been used in test for other things but then cut down. These trees did produce much sap but who's to say they would have continued for many years to come. Like I mentioned in another post there is a guy on Trader named Joe from Essex that taps some small trees. He charts his production and the numbers are very high. He may have been tapping 8-10 inch tree though and not smaller. I don't think any real research has been on long term affect to tapping a 6 inch tree. Ever sense the smaller spouts have come out people have been tapping smaller trees. I have never heard of anyone loosing their trees because of this. I think if a guy wanted to go out and tap 50 four inch trees under high vacuum he should. As long as you can afford to loose those 50 trees if things don't go well. If people don't try they will never know. Dreamers made this world not couch potatoes.:)

Spud

[Scribner's Mountain Maple]

Dr Tim,

Thanks for the great information as always. From this I feel confident in being able to determine when it might be "ok" to tap a smaller tree and when it may not. Not that you are saying it ever is. That I am clear on (not yet at least) If adequate light is reaching the crown due to another maple dying off or thinning, that may be a smaller dbh (6-10") range maple that can handle tap holes. This full/mostly sun scenario has the tree growing faster with less competition for nutrients. As opposed to the small dbh maple under the canopy that gets far less sunlight. Obviously the smaller tree with full sun will store more nutrients as it likely has more living limbs and leaves. This allows for it to handle giving up some sugar while still maintaining good new wood growth. Is this the gist of what you are saying?

I also tap small trees that have a disease. They are on the way out already, so why not get something out of them first.

Spud,

I would be interested to track this data. Man how does anyone have the time for experiments though. Someday... I would be interested to learn if it would be economical to tap a tree every other year while it develops. What characteristics allowed for tapping a small tree under high vacuum without killing the tree or stunting its growth (i.e. every other year tapping, opening up two sides to sun)? I'm sure there is a formula that can be applied as a general rule that will increase the pounds of sugar we can produce per acre. Something which I care more about than gallons per tap.

Ben

[DrTimPerkins]

I'm sure there is a formula that can be applied as a general rule that will increase the pounds of sugar we can produce per acre. Something which I care more about than gallons per tap.

Ahhh....now you're talking. All I can say right now is stay tuned....there will be considerably more of this kind of discussion ramping up within a few more weeks. I'll be talking about this in some detail at LEME, Verona, and the Vermont Maple Conferences.

[spud]

That Doc always has a few tricks up his sleeve. I look forward to hearing what he has mustered up in his maple lab. We just need to keep twisting his arm a bit and he will tell us how to get 1.5 GPT.:lol:

Spud

[DrTimPerkins]

Hi everyone -- I want to thank all of you who have already registered for the webinar presentation by Dr. Abby van den Berg entitled "Finding the Sweet Spot: Tapping Guidelines for Modern Sap Collection Practices" which is taking place on Wednesday, November 13, at 10:00 a.m. -- that's just one week from today!

There are still a few spots left, so for those of you who thought November 13 sounded like a long time in the future, you still have a chance to register now that it's snuck up on us.

I will forward instructions for logging in to the web presentation to all registrants next Monday. If you are planning to join us in person, please come to Room 311 in the Aiken Center a few minutes before the starting time.

Robin L. Orr, MPA
Research Assistant: Northeastern States Research Cooperative
Master's Candidate: Rubenstein School of Environment and Natural Resources
University of Vermont
robin.orr@uvm.edu
802-373-4446

[DrTimPerkins]

That Doc always has a few tricks up his sleeve.

I guarantee that there will be some scratching of heads with this one. See you in a couple of days at LEME.

[DrTimPerkins]

I guarantee that there will be some scratching of heads with this one. See you in a couple of days at LEME.

Now that the Trader is back on line, for those of you who weren't at LEME, and need a little head-scratching of your own.....

http://www.uvm.edu/~uvmpr/?Page=news&storyID=17209

[unc23win]

Now that is some very interesting material. I had wondered about the true amount of sap contained in a tree after cutting a maple tree down (downside of building in a sugar bush sometimes unavoidable) once and seeing a LARGE amount of sap gush out.

[happy thoughts]

Now that the Trader is back on line, for those of you who weren't at LEME, and need a little head-scratching of your own.....

http://www.uvm.edu/~uvmpr/?Page=news&storyID=17209

Wow. That's VERY interesting. Now you have me wondering if traditional tapping and maple farming might be combined for now as more research is being done. For instance, waiting until sap season to thin out saplings.

[DrTimPerkins]

For instance, waiting until sap season to thin out saplings.

That is one possible application.

[jrgagne99]

I wonder what the economics of applying vacuum to 6000 taps per acre would be. Obviously under this paradigm, there would be much more tubing, "taps" (or whatever you end up calling them), and vacuum cfms required per gallon of sap collected (due to more opportunites for leaks across 6000 "taps" vs. 80 taps). Perhaps the costs could be offset some by using smaller tubing, since the flows from each tap are reduced relative to traditional drops and laterals?

[spud]

Very interesting what PMRC is coming up with. I can't wait to read more about this.

Spud

[JoeJ]

Dr Perkins,
Could you tell us what the sugar content of the sap obtained by this method was, especially at the end of the season?

[Starting Small]

Very exciting news.....One thing that does not make sense to me.... Currently we should not tap trees less than 8 inches because of taking too much sugar from the young tree. How is it that we can take a 3 inch sapling and pull so much sugar from it and not harm the life of the sapling?
-Dave

[DrTimPerkins]

Could you tell us what the sugar content of the sap obtained by this method was, especially at the end of the season?

It is comparable to what you get from large trees. During an extended thaw, especially with single-stemmed saplings, the sugar content will drop off a little quicker than in a large tree. With multi-stemmed individuals, it is less so.

[DrTimPerkins]

Very exciting news.....One thing that does not make sense to me.... Currently we should not tap trees less than 8 inches because of taking too much sugar from the young tree. How is it that we can take a 3 inch sapling and pull so much sugar from it and not harm the life of the sapling?
-Dave

Hi Dave,

The primary reasons that tapping of small trees is discouraged are because of 1) internal wounding and 2) carbohydrate losses. In terms of the wounding, tapping will cause internal compartmentalization columns. With small trees, there is not a lot of wood, and growth rates may be quite low (especially for trees growing under the canopy), so that eventually you can end up with a large part of the internal wood being non-functional (unable to move sap or store sugar). Secondly, with small trees growing in the understory, they get very little sun, and thus the amount of sugar they can produce is low. Removing sugar (syrup) from them can reduce their growth.

With these sapling-sized trees in plantations, they all have quite good sun-exposure on their crowns. Juvenile trees are also wired for rapid growth if the conditions are appropriate. Trees try to maintain a stable root:shoot ratio and also seek to grow quickly (to achieve canopy status in the woods). So if you cut off the top, but don't impact the roots, the saplings put the majority of their effort into regrowing the top. By removing a good deal of the top and some sugar each year, we are simply keeping the sapling in a juvenile high-growth status. As long as the plantation saplings get adequate sun exposure on their crowns, they are fine.

[DrTimPerkins]

Actually the volume of your tubing system would be of a comparable size or even smaller. You would have relatively little mainline. Since the majority of your vacuum losses in a contemporary tubing system are frictional-line loss, a smaller system has considerable advantages. The possibility of leaks may certainly be higher (due to the necessity of having 6,000 bag collection devices per acre), but the line loss would definitely be far lower since the distances involved are WAY shorter.

Honestly, we aren't 100% certain of the best way to tube this type of system, but do have several ideas. The volume of sap produced by each stem per run is fairly modest, so I would expect we would have lateral line servicing as what we consider mainline in many instances, which should help keep the costs down. Lots more research to do for sure.

[spud]

Dr.Tim,

What you're saying is a person can take a (portion or the whole crown) off to extract the sap. I thought the sugar was made in the crown of a maple. How can sugar come up a 3 inch stem? In all my smaller test trees (both fall and spring) the sugar never seems to go above 1.0% About 25 years ago I remember saying to a friend that we need to come up with a way of forcing water through a maple log to make sap. Although that would not work we were always trying to come up with crazy ideas to get more sap. Your new system reminds me of a spindle system in apple production. With the help of wire you can now plant 1000 apple trees per acre and run irrigation pipe on the lower wire giving the trees both water and fertilizer. I guess the things I don't understand is how sap is coming from the roots up a 3 inch trunk that might only be 5 foot high and giving sweet sap? You can prune an apple tree and new branches grow fast. With a maple tree I always thought that they don't grow branches so fast.

Spud

[wildlifewarrior]

Hi Spud, I think your reference to the apple tree is a great one and I would say is an even better model for this than christmas tree farms. I believe the term we are referencing is coppicing which is something that use to be done a lot in England to stimulate growth of trees. Like Dr. Tim said you are basically keeping the tree in a state which wants to send up more shoots to try and take advantage of the ample light. When you remove the apical meristem the tree bushes out some until it establishes a new apical meristem either later in the season or in the following year (Dr. Tim, I think I am going in the right direction). So if my understanding is correct when you undergo this process all of the dormant buds in either the base of the tree or in the stem, would send out the shoots for the next season.
My question Dr. Tim would be if you would tap the same stem or a different stem each year, or would you have to allow the axillary stems to develop and you would only be able to utilize the sapling every few years?

Also where is all that sugar coming from? It is impressive if the tree is only utilizing the sugar stored in the roots, where it would get the other sugars, I don't know, but it is amazing to think that there is enough sugar stored. Do the saplings have an extensive enough root system to have significant yields of sugar content for the extended season? I know you guys are still working on this but these are just some questions that popped up

Mike

[Scribner's Mountain Maple]

Dr. Tim, This could be an interesting thing to consider on an acre. At 6,000 trees per acre you are talking a tree every 2.75 ft +/- in all directions from my calculation. That is a little tight in terms of walking lanes and mowing etc. 77 taps in a row, 77 rows. What kind of fertilizer would be used?

Could use that double 5/16 line that I heard you mention before and get a little less than 2.5 rows (186 taps) per 500' roll and give each shoot a wet dry set up. That would be a pretty economical way to get high vac to 186 taps.

A few questions, how well do the bags seal I wonder? Can I add this method into my existing woods where a lateral line passes several shoots and not worry about leaks? In a plantation it would be easy to maintain leaks as you are in a field, on flat ground in close proximity. All of which are things I do not have in my current woods. They are steeeep, far away to walk and not in a field:D

Another question about those trees to small to tap. Can you take a pair of pruning shears and cut a low branch approx. 1/2" in Diameter and stick a bag sucker thing on it? This way you are not tapping into the fragile wood of a tree you want to achieve maturity. But at least you are tapping it as opposed to walking by it year after year watching it grow slowly. I know it may slow it's growth, but would that matter? I would guess that you would get much more sap using this method and harvest from the tree an extra 10-20 years over the life of the tree.

Good stuff, now you are talking pounds of sugar per acre. holy crap.

Ben

[Loch Muller]

Wow! I've been just reading through older posts to learn more about sugaring so far, but this one is really something. I'm a forester by trade and it fascinates me to see the coppice system tested in a way that brings forestry, agriculture, and the heritage of maple sugaring together all at once. I'll definitely have to go down to Verona this winter to see what Dr. Tim has to say about it then.

One thought that jumps into my mind is if something like this could be used with what foresters would call a 'coppice with standards' system. The 'standards' being larger trees dispersed through out the acreage. The 'standards' could be larger maples or something completely different (nuts, fruit, valuable timber....), maybe a good way to diversify an operation. I've heard of this being done in Europe with beech and oak (oak being the standards). Definitely something worth more thought, for me at least.

Bill

[DrTimPerkins]

What you're saying is a person can take a (portion or the whole crown) off to extract the sap. I thought the sugar was made in the crown of a maple. How can sugar come up a 3 inch stem? In all my smaller test trees (both fall and spring) the sugar never seems to go above 1.0%

Sugar is made in the leaves during the summer and stored in the stem and roots for the winter. The crown (branches and leaves) is removed only for collecting the sugar, then latent buds in the stem will resprout to develop a new crown during the next growing season. Using multiple-stemmed saplings you would only remove one stem each year, so you're not impacting the total crown as much.

Sugar comes up a 3" stem the same way it goes up a 20" stem. Little difference overall. With vacuum you are simply sucking water from the soil up through the roots and stem, where it mixes with sugar, and then the sap comes out the cut surface. Pretty simple actually.

The reason your sap sugar was so low in those small trees is that they were growing in the understory. Put them out in the open where they get plenty of sun and they'll make a lot more sugar.

[DrTimPerkins]

Dr. Tim, This could be an interesting thing to consider on an acre. At 6,000 trees per acre you are talking a tree every 2.75 ft +/- in all directions from my calculation. That is a little tight in terms of walking lanes and mowing etc. 77 taps in a row, 77 rows. What kind of fertilizer would be used?

Could use that double 5/16 line that I heard you mention before and get a little less than 2.5 rows (186 taps) per 500' roll and give each shoot a wet dry set up. That would be a pretty economical way to get high vac to 186 taps.

A few questions, how well do the bags seal I wonder? Can I add this method into my existing woods where a lateral line passes several shoots and not worry about leaks? In a plantation it would be easy to maintain leaks as you are in a field, on flat ground in close proximity. All of which are things I do not have in my current woods. They are steeeep, far away to walk and not in a field:D

Another question about those trees to small to tap. Can you take a pair of pruning shears and cut a low branch approx. 1/2" in Diameter and stick a bag sucker thing on it? This way you are not tapping into the fragile wood of a tree you want to achieve maturity. But at least you are tapping it as opposed to walking by it year after year watching it grow slowly. I know it may slow it's growth, but would that matter? I would guess that you would get much more sap using this method and harvest from the tree an extra 10-20 years over the life of the tree.


Just too many questions to address here in depth. I'll be presenting this work at Verona and the VT January Maple Conferences. Briefly however....

Our preferred spacing is 2' between trees within rows, 2.5' between rows, with every 3rd row left out, thus leaving a 5' wide corridor between every pair of rows for access to "tap" and mow or other activities.

Fertilizer and irrigation needs would depend upon the land and it's moisture retention and nutrition.

Double-line....quite possibly. This would also allow a quick and easy way to clean lines (pump water or cleaning solution up one line and suck it out the other).

The bags seal quite well. We use a thick and wide rubber band over the stem, then the bag, then another rubber band, and finally a band clamp. Nice and tight.

The smaller the stem, the less sap you'll get. Best production is about 1.5-2" dbh. Much above that and resprouting ability of the stem diminishes.

Cutting branches would depend upon the height. You can't suck sap up too far (physics).

[DrTimPerkins]

.. if something like this could be used with what foresters would call a 'coppice with standards' system. The 'standards' being larger trees dispersed through out the acreage.

Yes, that is one application. You could collect from the smaller stems, but have some of them not cut and develop into mature trees. The trick there is to make sure your density of mature trees is not so high that it would seriously restrict light hitting the smaller trees, reducing photosynthesis and thus the amount of sugar you could get from those stems.

[spud]

Dr. Tim,

I do understand the low sugar is because of the (understory) trees in my woods. I guess what I don't understand is how you're getting good sugar from your cut off saplings. The photo of you and Dr. Abby show a 3 inch sapling with no branches cut off at about the 5 foot mark. All I'm seeing is a bag on top sucking the sap out. So even planting 6000 of these sapling on an acre with full sun with small branches growing out from all sides should not be enough to produce high sugar. My understory trees still would have far more branches and leaves then your cut off saplings I would think. What am I not understanding? Based on your 400 gallons of syrup per acre you would have to be getting 3-5 gallons of sap from each sapling. Is this about what you're getting for sap production? I find the whole thing very interesting but as you can see I still have a lot to learn. Thanks Doc.

Spud

[DrTimPerkins]

Based on your 400 gallons of syrup per acre you would have to be getting 3-5 gallons of sap from each sapling. Is this about what you're getting for sap production? I find the whole thing very interesting but as you can see I still have a lot to learn.

Exactly. If you put a regular tap in the sapling you wouldn't get nearly that much. We all still have a lot to learn about this method.

[Loch Muller]

Dr. Tim,

You are right about managing the light intensity reaching the under story in a coppice with standards system. No easy trick, but I'd think that a residual basal area around 20 to 30 square feet per acre would provide ample amounts of light. That is well below a fully occupied site by the standards, even if they had large crowns. The major flaw I'm seeing right now with a system like that is that if you have the need or desire to harvest your standards you would have to remove tubing and irrigation systems to avoid damaging them. The standards would also be more exposed than woods trees and prone to windthrow, especially if the soils limit rooting depth. Windthrow would make a general mess out of things and reduce production and profits.

The silviculture literature I have around suggests that sprouting capacity is better when cuts are done during the dormant season, that fits well with a sugaring operation. It also suggests that sprouts close to the ground are better quality than ones higher up the stems. Have you seen that the height of cutting makes a difference in the quality of sprouts for maple sugar production?

Bill

[Loch Muller]

One more thought, then I'll try to stop rambling.

Herbivory by deer could be an issue as well in some areas. This can definitly be managed, but at a cost. Perhaps the sprouts would be vigorous enough to stay ahead of the deer, but I wouldn't get my hopes up. Thanks for taking the time to reply Dr. Tim, this is really interesting.

Bill

[DrTimPerkins]

It also suggests that sprouts close to the ground are better quality than ones higher up the stems. Have you seen that the height of cutting makes a difference in the quality of sprouts for maple sugar production?

As a general observation that is true. It is not something we've thoroughly studied yet, but there is a good amount of literature available on the subject.

[DrTimPerkins]

Herbivory by deer could be an issue as well in some areas. This can definitly be managed, but at a cost.

That is true, yet manageable, at a cost.

[cjf12]

Was curious, as an arborist you would never think of doing this to a tree but can understand the value of it just like harvesting any crop. Although with most crops you tend to remove from year to year and rotate as well so disease is managed to a great extent. How long have you been researching this technique on the same trees and if for long I was wondering if you were running into problems with things like verticillium wilt. Topping is bad practice and repeated may cause a breeding ground for different disease issues.

[DrTimPerkins]

Topping is bad practice and repeated may cause a breeding ground for different disease issues.

We have been doing this for 4 yrs and have seen no problems. It is technically possible for diseases to be introduced in this process, just like it is technically possible for tapping to introduce diseases. In practice, maple trees are pretty resistant to many of these problems, but in certain instances it can be an issue.

Topping is unusual in maple, however it is not at all an unusual process when one considers coppicing and pollarding, which have been done for centuries.

[afretired]

Dr. Tim
That article was great...This opens up a whole new bunch of possibilities. From the article it sounded like some of the traditional sugar producers look down on this technology. But from my stand point where we don't have "established" sugar bushes that have been maintained for generations, and we are too old to start a new sugar bush, the sky has opened up. I've been looking around for more trees to tap, there are several around, but one industry that is prevalent around here is logging. And nobody that has any mature woods will let you come and tap their maple trees if it is going to put brown streaks in the wood. For practical purposes it ruins the tree for lumber.

But now here comes Dr Tim to save us, and pump some hope into the process. One thing we have plenty of is rough ground that is not suitable for much of anything except running cattle. But the possibility of turning it into a viable sugar bush in a few short years is very interesting. additionally this has the possibility of getting more people involved in areas, such as ours. I for one am going to check into this with our local conservation office and see if we can get saplings through them. Or do you know the most economically source for maple saplings.

You mentioned the actual hardware wasn't available yet, have some of the major manufactures shown any interest in producing parts?

I for one plan on setting some trees this spring in anticipation of more information, what would be the worst that could happen, I started a sugar bush for my grand kids?

Again this is great news...Keep us informed.

David

[DrTimPerkins]

... have some of the major manufactures shown any interest in producing parts?

We have had some initial discussions with a few manufacturers. Given the time of year, we just talked about it, and agreed to meet again after the season. We're in hopes there will be some type of product ready for the 2016 season.

[Indiana-Jones]

Afretired, I'm with you right on down the line. We are new to sugaring and don't have the bush that takes generations to fine tune. A old cow pasture is spot on for this new type of Maple Production. I'm looking to learn a bit more about the process and set out a couple of acres of saplings maybe next fall.

Dr. Tim, has any thought or tests been conducted with box elder trees in this plantation style bush. I have some bottom ground that is full of them and it seems to me that they have a disposition to sprout side shoots and grow at a higher rate than hard maples. I may run some tests of my own on sugar % and see if I can grow me some super sweet box elders.

Thanks for the research Dr. Tim and I have been voting twice a day.





Dr. Tim
That article was great...This opens up a whole new bunch of possibilities. From the article it sounded like some of the traditional sugar producers look down on this technology. But from my stand point where we don't have "established" sugar bushes that have been maintained for generations, and we are too old to start a new sugar bush, the sky has opened up. I've been looking around for more trees to tap, there are several around, but one industry that is prevalent around here is logging. And nobody that has any mature woods will let you come and tap their maple trees if it is going to put brown streaks in the wood. For practical purposes it ruins the tree for lumber.

But now here comes Dr Tim to save us, and pump some hope into the process. One thing we have plenty of is rough ground that is not suitable for much of anything except running cattle. But the possibility of turning it into a viable sugar bush in a few short years is very interesting. additionally this has the possibility of getting more people involved in areas, such as ours. I for one am going to check into this with our local conservation office and see if we can get saplings through them. Or do you know the most economically source for maple saplings.

You mentioned the actual hardware wasn't available yet, have some of the major manufactures shown any interest in producing parts?

I for one plan on setting some trees this spring in anticipation of more information, what would be the worst that could happen, I started a sugar bush for my grand kids?

Again this is great news...Keep us informed.

David

[afretired]

Dr. Tim
I'm still thinking about this new process and trying to get prepaired to plant some trees. If something comes up the trees still would be a good idea. Have you gave any thought about how you can deal with all the brush that will be generated in the field when you cut the top out of the trees? with the trees planted so close together it would be a lot of work packing the branches out, and if you left lanes big enough to get a tractor and wagon in the field it would take up a lot of area. What about pulling a small mulcher behind a lawn tractor and mulchiong as you go? Maybe plant two or three rows then skip one for access? The mulch could also be used to control weeds. Just a thought.

David

[DrTimPerkins]

Maybe plant two or three rows then skip one for access? The mulch could also be used to control weeds.

That is exactly what our preferred configuration is. Two rows, then a third left unplanted. This would allow good access.

As for the brush generated -- it could be chipped and used for mulch or evaporator fuel.

[Bemis]

300 bare root saplings went in today. Half sugar, half red. Spaced 2 foot in rows 2.5 inches apart. Every third left out. Looking forward to 2020.

[KevinS]

Here in Il. our DNR's recommendation when planting saplings is to let the weeds take over for several years, they say it reduces the pressure from grazing deer, while this is probably 100 percent true, I did notice that the damage from bucks removing velvet was much greater in those trees, than the trees we did mow around.
I too am loving this since I have about 150 bushes now.

[KevinS]

300 bare root saplings went in today. Half sugar, half red. Spaced 2 foot in rows 2.5 inches apart. Every third left out. Looking forward to 2020.

Nice :)
fall is better. But sooner is good too :)