Tapping & Timber: Monthly Maple REVIEW

After a several months long hiatus from our REVIEW articles, we are going to dive back into a Quebec research 2’fer that examines the effects of tapping on sugar maple tree growth rate and timber accumulation.  The Ohio State Maple team hosted a day’s worth of Maple Madness as a stop along the Ohio Tour less than 48 hours ago.  While giving sugarbush tours, hands down the most frequent question I fielded was whether tapping hurts the trees.  While some research has attempted to answer this question over the past decade or so, 2 relatively new studies out of Quebec take aim on this subject.

The question “does tapping hurt a maple tree?” can be answered from multiple different perspectives.  You might respond by citing information about the small percentage of a maple tree’s overall sap that is harvested through the tapping process, even with a high vacuum system.  You might make an analogy that a taphole is similar to an insignificant injury and point out that healed tapholes are barely visible to the eye just a year or less later and the percentage of compartmentalized wood is miniscule.  You might have another way of replying to that question.  The article “Effect of tapping for syrup production on sugar maple tree growth in the Quebec Appalachians” and the paper “Assessing the effects of sugar maple tapping on lumber production” provide additional insights to this delicate topic.

Before we dive in, a few caveats:

  • Caveat #1 – this issue has been addressed by different studies through different research labs through time, I’m examining these 2 studies today because they are recent and both from the same geographic area, Quebec.  Perhaps we will address some of the other work conducted in this space in future REVIEW articles.
  • Caveat #2 – The studies are from Quebec.  Stated another way, these studies are not directly applicable to Ohio, but we can certainly learn from them regardless.
  • Caveat #3 – both studies are based on tapping recommendations that encourage tapping to begin when a tree is 7.5-9.1 inches in diameter.  This recommendation in comparison to more conservation guidelines that we teach locally of 10″ minimum before tapping layered in with the fact that growth productivity is higher in Ohio than Quebec, and we have additional reason to not assume 1 to 1 transferability of results.

The study that focuses on tree growth rates was conducted by a foursome of researchers (Ouimet et al.) back in 2021.  They examined tapped and untapped trees within 7 Quebec maple woods on vacuum tubing systems.  The normal stringent criteria were applied to ensure trees in each group were as similar as could be except for the main treatment variable: tapped or not tapped.  Ouimet and crew worked off a primary hypothesis that tapping sugar maple trees would remove enough of the non-structural carbohydrates (sugars) that tree growth rates would be higher in untapped trees versus tapped trees.  Restating their hypothesis another way, extracting sap from sugar maples is in direct competition with resources needed for tree growth.

What did they find?  In 6 of the 7 sugar bushes, there was no effect of tapping on tree growth rates.  In the 7th site however, tapped trees grew 33% slower over the tapped year period (10 years) than did the untapped trees.  A partial explanation seemed to be that soils in that particular forest were strongly Ca-deficient; however, similar decreases in tree growth rate were not observed in 2 other woods that also suffered from low Ca levels.  Truth to be told, the team was scratching their heads a bit over the inconsistent results stating the “relatively small NSC [non-structural carbohydrates] allocation to syrup production might explain why we did not find a consistent tree growth response to tapping.”  In the most elementary of terms, tapping did not seem to trouble the majority of trees in the study.

The second study coincidentally also featured a four-person research team, and the research utilized data from 17 different sites within Quebec’s public forests.  Forest stand management scenarios (how and when to harvest trees) and lumber yields were simulated using a model that gathered data from over 2 thousand individual trees.  If taphole-stained maple lumber does in fact have niche value in local and regional niche markets, I would quibble with blanket statements such as the one they provide in the Introduction citing the National Hardwood Lumber Association – “Tap holes are considered defects, and they diminish the manufacturing value of boards.”  But the purpose of the work is clear, does tapping affect traditional lumber value of sugar maple logs?


Photo: Firth Hardwood Export Logs

What did they find?  Unsurprisingly, the answer is yes.  Of course tapping reduces net lumber volume in sugar maples, and tapping reduces the probability of an individual tree yielding a 10 foot saw log.  The details are what I found especially interesting.  Trees in the study were binned into 4 different health categories.  Trees with fungal infections, rot, or noticeable crown dieback were impacted by tapping more than trees that were healthy by visual measures.  While this too is unsurprising, I was most impressed by the findings that tapped sugar maples have a 85-90% chance of still yielding a 10′ saw log.  However, net lumber volume is still markedly reduced by tapping as the vertical segment of the trunk sectioned by the lowest and highest tapholes (or “butt log”) is defect.  Guillemette et al. concede in the very first paragraph of the Discussion that their results do not account for “craftspeople sometimes use these butt logs to produce boards with specific features resulting from tap holes or stain.”  I appreciated this admission.  Even so under a more traditional notion of what is valuable maple lumber, a notable rule of thumb emerges from their Implications for Management.  “Tapping reduces the net standing volume of sugar maple timber by approximately 40% and reduces the harvestable volume after the first 30-year cycle by approximately 40%.”  Economic modelling of one-time profits due to timbering need to be compared to the year-over-year return on investment from sugaring a maple woods, but the study does provide some interesting ways to frame and think about our original question – does tapping hurt a maple tree?

WV Maple Event Opportunity

Southern Ohioans have a great opportunity to slide across the Ohio River to join a wonderful maple event scheduled for October 14th in Wayne, West Virginia.  Just across the water from Lawrence County, OH, our partners at Future Generations University and West Virginia University are putting on a workshop titled “Forest Management for Sap Production: Why You Should ‘Think Maple’ .”

Lunch is provided and the workshop goes from 9:00 AM to 4:30 PM and features sugarhouse and sugarbush tours at Tom’s Creek Maple.

Specific talk sessions are as follows:

  • Managing for sap production / Managing for timber production / or both!!
  • Sap collection systems
  • Managing a woodlot for sap production (hands-on and forestry tech talk heavy)
  • Integrating other forest farming activities into your sugaring operation
  • Forest health threats to maple
  • Technical resources through the OH/WV Maple Toolbox

Slots can be reserved by emailing syrup@future.edu.  Don’t miss out on a great learning opportunity to learn from syrupmakers in the far southern tier of what Ohio producers can expect to encounter in maple sugaring.

PA Maple Boot Camp Recap

Maple Boot Camp rotated over to Pennsylvania for 2023 after we hosted it last year in ’22.  The agenda delivered a wealth of information to 20+ lucky attendees who came from backgrounds of “I’ve never tapped a tree before” to “I’m looking to expand into that medium-large producer category.”  Speakers from Ohio, West Virginia, and Pennsylvania served to make Boot Camp a huge success – a special thanks to Mike Lynch of Baer Brothers Maple for hosting the in-field workshops in his sugarbush and sugarhouse.

Kate Fotos, Les Ober, and Mike Rechlin taught a maple grading seminar to attendees who elected to show up early for a pre-Boot Camp workshop.  Day 1 covered discussions of tree identification,  site and woods evaluation, sugarbush inventory, and tree health assessments, and spanned indoor sessions with outdoor hands-on lab time.  After a wonderful catered dinner, Steve Childs tackled night one of value-added maple products and demonstrated maple sugar and maple cotton candy.  Here is a link to the New York State Maple Confections Notebook that is a testament and legacy to his lasting impact on the maple industry across the region.

Day 2 kicked off with a flipped itinerary to accommodate weather conditions that were less than favorable.  Kudos to everyone’s flexibility and Scott Weikert’s boldness to turn the agenda on its head.  It is hard to imagine the day going much better than it did!  While night two of maple confections featured maple cream and maple candies back in the meeting event space, the vast majority of the day took place in the sugarbush at Baer Brothers Maple.  Sap collection methods and detailed demonstrations of installing and maintaining main line, lateral line, and drop and spout configurations filled the morning.  After a bagged lunch, best practices related to tapping and sanitation practices took center stage.  Semi-structured lectures interspersed with lots of hands-on demonstrations and opportunities for workshop attendees to try their own hands at different skills and techniques carried the day.

While I was not able to stick around for the third and final day, everyone once again caravaned out to Mike’s sugarhouse to see his reverse osmosis and evaporator set-up.  This is such an important component of workshops, but due to time of year, sometimes gets the short end of the stick.  Not this time.  Mike had his system primed with water to get all the steam and the burn which takes an off-season experience to the next level.  Attendees were lucky to enjoy an afternoon closing session on financial planning, operation economics, sales and marketing from one of the best in the industry – Mark Cannella from UVM.

Planning for Maple Boot Camp version West Virginia is already afoot for 2024 – as details begin to fall into place, you can be sure we will share all of the relevant details!

Maple Regeneration: Monthly Maple REVIEW

July’s REVIEW piece lands on the subject of maple regeneration.  Put simply, how do big trees make baby trees and what factors promote or inhibit that process.  This review comes courtesy of a doozy of a 2021 titled paper “Complex drivers of sugar maple (Acer saccharum) regeneration reveal challenges to long-term sustainability of managed northern hardwood forests.”  The team of authors, all from the mitten-shaped state to the north, was led by Catherine Henry from Michigan State’s Department of Forestry.

It goes without saying that it requires a whole bunch of seeds to hit the forest floor in order for a single tree to reach maturity decades later.  But just how complex is the regeneration struggle for sugar maples?  After all, despite a lifespan of 300 years give or take a century, if mature sugar maples do not replace themselves with seedling, sapling, and teenager sugar maples, the ultimate goal of passing one’s genes on to the next generation will fail.  Henry et al. examined research plots in 141 different forest stands to dig into factors related to sugar maple regeneration throughout northern Michigan.  The study sites were all managed with single-tree selection silviculture for decades, a forestry practice that is commonly regarded to be a great tool for regenerating and recruiting sugar maple.  It is important to note potential geographic differences between the study’s region and Ohio; not everything will necessarily apply to our state, but we can learn from their findings as well.

Sugar maples are generally considered to be shade tolerant tree species, and that is a fine way to categorize them from a 30,000 feet above the surface of the earth perspective.  Zoomed in up close however, a simple shade tolerant descriptor is insufficient.  Sugar maple regenerate best under conditions of intermediate canopy openings, and successful production of seedlings and saplings is optimized in larger single-tree gaps that are maintained or increased through time.  The truth is that while maple seedlings are technically shade tolerant, more light is required as regeneration grows into sapling sizes and beyond.  Prolonged deep shading stunts out maple regeneration, and it is important to remember that shade doesn’t just come from overstory trees; ferns, dense midstories of beech, and invasive plant infestations can all starve a cohort of seedlings of the light they require to become saplings and ultimately larger trees.  In addition to growing space, variables of deer browsing pressure, site quality (related to soils), and competing vegetation were considered.

The very first line of the study’s Results section reads as follows: “Stand-level sugar maple regeneration was highly variable within and among size classes.”  It goes without saying that nature contains tremendous variation, and this statement reinforces that idea.  Examining one forest stand and anticipating the next forest to behave identically is foolish, and taking one study and assuming that it directly applies to a novel new region is equally foolish.  All that said, there are absolutely some lessons to be learned.

Maple regeneration was most successful at intermediate basal area levels and at sites with intermediate quality.  Imagine an upside-down U where the peak is in the middle and the start of the curve and end of the curve are low, that’s essentially what the graph would look like.  This plays well with the Goldilocks analogy that we like to use for sugar maples – sugar maples favor conditions that aren’t too _______ but also aren’t too ________, just like Goldilocks didn’t dive straight into a bowl of scalding hot or freezing cold porridge.  The study had some educated guesses as to why this may be.  Excessive basal area (a forest stand that is overstocked) and too many sugar maples in the overstory casts deep shade that even the shade tolerant maple babies can’t survive.  Too few mature maples in the overstory may be limited by seed availability and more easily overwhelmed by deer browse pressure (see photo above).  Low quality sites for sugar maple, duh, did not have a lot of vigorous healthy sugar maples.  But high quality sites were often associated with higher deer densities that likely led to overbrowsing of seedlings and smaller saplings.  An additional explanation is that overstory maples grow so quickly on high quality sites that canopy gaps quickly close thus reducing understory recruitment.

https://oregonforests.org/field_collection_item/485

The study is published in the journal Forest Ecology and Management, and authors are encouraged to write a rather in-depth closing section called “Implications for management.”  In these parting paragraphs, Catherine Henry and her colleagues boldly comment that single-tree selection silviculture – a system that ought “to produce ample sugar maple regeneration” – is failing.  While the study’s results were highly variable, factors of deer overbrowsing, site quality, light limitation, and seed availability confounded attempts to successfully recruit sugar maples to the sapling size class in nearly 70% of plots.  The solution is not easy or obvious.  While the authors point to silvicultural harvest methods that open more growing space and release more light into the understory – namely uneven-aged group selection and even-aged shelterwood harvests – they acknowledge a different approach may exacerbate other problems (denser shrub densities, higher success of undesirable species).  Regardless of harvest method, a parting recommendation was that managers take deer population management seriously through increased hunting take or use of exclusion practices, such as wire fencing or natural slash walls.

Bringing this review home to Ohio, what are the over-arching takeaways.  While there are undoubtedly more to consider, I’ll quickly point to 3 recommendations.  #1 – Deer can destroy even the best laid plans, our state mammal HAS TO BE managed.  The best possible silvicultural plan can quickly unravel with too many deer.  #2 – Cutting a single tree here and a single tree there is not likely to recruit your next generation of syrup-making trees.  #3 – Work with a state or credentialed forester to develop a management plan for your woods.  They will understand the complexities and caveats to navigate a timber harvest and help you balance your objectives against the impacts of the past, the conditions of the present, and the goals for the future.

 

Out of the Woods Webinar UPCOMING

The Out of the Woods webinar series continues this Thursday night, July 20th at 7 PM out of our partner Future Generations University.  The Appalachian Forest National Heritage Area (AFNHA) is featuring on this month’s event and will have agroforestry experts speaking to the life of a forest and the benefits these different living organisms bring to the ecosystem.  It might not be as maple-focused as it usually is, but the focus on holistic forest integrity should be integral to any maple producer’s mindset.

The AFNHA “conserves, interprets and promotes forest heritage to enhance landscapes and communities” throughout regions of Appalachia.  Though their focal area are specific counties of Maryland and West Virginia, there is much to be learned from their unique approach to asset-based tourism and community development in heavily forested landscapes.  Here is a beautifully done webpage within their site that walks through the seasonality of different forest edible plants and derivatives.

Register Here Now.

Pennsylvania Maple Boot Camp: REGISTER Now

Maple Boot Camp is going on the road for 2023 and pit-stopping with our neighbor to the east: Pennsylvania.  Scott Weikert and the good folks at Penn State University are hosting this year’s event from September 6-8 in Somerset, PA.  The agenda is fairly similar to last year’s event that we hosted at the OSU-Mansfield campus during the month of June.

To kick things off, attendees can sign up for a bonus maple syrup grading workshop morning of Wednesday September 6th.  The registration link is here.

The official Maple Boot Camp will kick off right after lunch that same day and continue for two and a half days through Friday mid-afternoon.  We hope to see you in Pennsylvania for this signature maple educational opportunity.  It is an excellent deep dive for beginners or small producers thinking about growing their operation.  Veterans will undoubtedly learn a thing or 3 though too as they interact with maple experts and producers from West Virginia, Pennsylvania, Ohio, and New York.

The Pennsylvania Maple Camp provides intensive, hands-on training for beginner and intermediate maple producers.  The 3-day curriculum begins with sugarbush assessment, then builds sequentially through all phases of maple syrup production from sap collection to boiling, bottling and sales.  Participants will gain the skills necessary for the safe, efficient, and profitable production of maple products.  Camp will include classroom lectures as well as outdoor, hands-on exercises.  Come one, come all, see you in Pennsylvania for Maple Boot Camp!

Maple Cost-Share Assistance – NRCS EQIP Program

Special thanks to Keith Libben & Timothy Fulks for writing this article for the OSU Maple site!

The USDA Natural Resource Conservation Service (NRCS) has long been a well-known resource for agricultural producers in Ohio, especially with our livestock producers and our crop farmers.  Their Environmental Quality Incentives Program (EQIP) is the flagship conservation program for NRCS and has provided millions of dollars in incentives to producers over the years to address resource concerns that negatively impact soil, water, air, and animal health.

EQIP works by providing farmers, ranchers, and forest owners financial incentives to install conservation practices that help address resource concerns.  Common practices funded include cover crops, manure storage systems, and nutrient management planning.  But did you know that EQIP can now assist Ohio’s maple syrup producers?  Recent changes to the practices available in Ohio intended to improve air quality can now provide some assistance in the sugar shack.  The practices available are intended to improve air quality by improving efficiency in the sugar shack and in turn reducing emissions from burning fossil fuels or wood.  Practices that are currently eligible include reverse osmosis systems, sap pre-heaters, and improved efficiency evaporators.

Interested in getting some financial assistance to make some upgrades at the sugar shack?  This is the general process:

  • Producers need to reach out to their local NRCS field office or Soil and Water Conservation District and get an application in for EQIP.
  • From there, NRCS will coordinate with you to set up a time to visit your sugar bush and assess your operation. Other professionals may be necessary to determine what practices may be appropriate for your operation.
  • NRCS will use this information to develop a conservation plan and cost share estimate. Once this is complete, your application will be submitted for ranking and consideration for funding.
  • NRCS will reach out to you if your application has been selected for funding. Now the ball is in  your court to decide if you want to sign a contract for the funding assistance.  If you sign the contract, you agree to install the required practices per all relevant NRCS standards and specifications.
  • Once installation of the practices is complete and verified, you’ll receive your contracted financial incentive.

It is important to not think of EQIP as solely a coupon to get a steep discount for a new evaporator or reverse osmosis unit.  Such narrow thinking will probably not result in a competitive conservation plan.  Rather, leverage EQIP to design a more holistic approach to improving your overall property.  Additional woodland, wildlife, or cropland practices can also be applied to increase your plan’s ranking score and up the odds of being successful.  Talk to your local NRCS office today to see how they may be able to help!

Additional Questions:

How much cost-assistance will I receive?  NRCS re-evaluates costs of implementing practices on a yearly basis.  For most successful applicants, they will receive their contracted payment of 75% of the projected cost upon completion.  For historically underserved applicants, the cost share rate is set to 90%.

What are the maple-specific EQIP practice codes?  Practice 228 Agricultural Energy Assessment and Practice 374 Energy Efficient Agricultural Operation are the codes that can be leveraged for evaporators, sap preheaters, and reverse osmosis units.

When do I need to get my EQIP application submitted?  NRCS accepts new applications on a continual basis, meaning there is no true deadline.  However, submitted applications do join a stack of documents for the next ranking session which typically occurs in late fall.

 

Remember to join us on Saturday, December 9th for the 2023 Ohio Maple Days.  One of our featured afternoon speakers this year will discuss EQIP’s cost-share opportunities for maple producers in detail.  Registration should go live in late July-early August.

Borers, Feeders, and Galls Oh My!

Ohio Maple Days 2022 did not disappoint.  The food was fantastic, the vendor room crowded, and the presenters shared a wealth of knowledge of expertise across a wide range of subjects. Dr. Curtis Young, Entomologist, Extension Educator, and Associate Professor, expanded our knowledge regarding maple pests.  Many that most of us were already aware of, spotted lanternfly or Asian long-horned beetle for instance, and lots of lesser known pests.  Before we get into a few highlights, be sure to mark your calendars for next year’s conference December 8th and 9th!

Any attempt to summarize Dr. Young’s talk would fail due to the sheer amount of information that he is able to share in such a short amount of time.  And no notes!  Truly a wealth of knowledge.  Rather than attempt a synopsis, this is a great opportunity to share some general resources and up-to-date information for some of the more alarming maple pests we face here in Ohio.

University of Kentucky Extension has a great webpage that quickly catalogs a wide range of known pests across 4 general categories – leaf feeders, sap feeders, borers, and galls.  While most maple pests are just that – pests, similar to how most of us view the average mosquito, a few present a real and present danger.  That said, if your maple trees are stressed already, a relatively harmless pest can be the proverbial straw that breaks a camel’s back.  Moral of that last sentence, practice healthy silviculture and sugarbush management to ensure your trees are healthy and vigorous.

Asian long-horned beetle are always mentioned in these presentations.  Thankfully, in Ohio at least, control and eradication of Asian long-horned beetle is a success story that we seldom get to herald in the fight against invasive species.  While we keep our eyes out for future infestations, spotted lanternfly has rapidly expanded its range and our state records now show several counties with positive detections.

An excellent website to stay abreast of issues facing plant, shrub, and tree health is Buckeye Yard & Garden onLine where Dr. Curtis Young and many other experts from Ohio State University Extension provide “timely information about Ohio growing conditions, pest, disease, and cultural problems.”

Not Just Sugar Maples – Part I

Ohio Maple Days 2022 did not disappoint.  The food was fantastic, the vendor room crowded, and the presenters shared a wealth of knowledge of expertise across a wide range of subjects.  I was among those speakers, and Abby van den Berg and I presented a pair of talks that focused on those other maples.  Abby’s perspective from Vermont and focused mainly on pure red maples (come back for Part II next week for those highlights), and my perspective sharing from the basis of our ACER-funded research on Acer freemanii, Freeman’s maple, or just “rilver” for short.  Before we get into it, be sure to mark your calendars for next year’s conference December 8th and 9th!

Let’s try this recap in a series of short statements.

1) Sugar maples are the gold standard for maple syrup production – there is no disputing that.

2) But other maple species probably deserve more love than they have traditionally been given.

3) Mounting pressures from climate change, forest pests, and a host of other reasons make other maple species more important to consider than ever before.

4) Because of the above, it makes sense to learn more about other maple species production potential.

5) We thought we had simple (red x silver) hybrid maples in the OSU Mansfield research sugarbush where we have our single-tree research stations.

6) We thought wrong.  Turns out the hybrid maples are more mysterious than that – stay tuned for further genetic testing!

7) Regardless of what other variety of maple we are working with it still made sense to compare their production potential and other characteristics to sugar maple.

8) Research began in the 2021 as we pulled over 20 sugar maples and 50 of the mystery maples into single-tree sap collection chambers that measured daily performance.

9) Research techs and research PI quickly learned that maple research can be icy cold!

10) The 2021 season was historically bad and we had 5 roller coaster runs total.

11) During the 2021 season, our mystery maples were not as sweet overall as sugar maples, however, the mystery maples held a more stable Brix level from the start of the season to finish.

12) Mystery maples lost ground to sugar maples in terms of sap production volume as the season got later and later.

13) Surprised yet?  Maybe not.  But consider this – the best half of our mystery maples OUTPERFORMED the worst half of our sugar maples in terms of syrup production potential.  Would that also hold true for 2022?

14) Fast forward 11 months to yet another choppy, wild, and erratic 2022 sap season.  When will we have another “normal” sap season?

15) Note to self, might have to add another 10 degrees to y-axis of Sap Run graph in 2023.  I surely hope not!!

16) More in line with studies elsewhere, our 2022 mystery maple trial trees matched or outpaced sugar maple’s sap volume production up until the final sap run of the year.

17) Brix consistently tracked 0.2-0.4 points below for mystery maples as compared to sugar maples.

18) Ultimately, we’re excited and hopeful for a “normal” 2023 season to collect data from a more representatively average season.

19) In the interim, both years suggest that mystery maples are not to be overlooked especially if you are an operator using reverse osmosis in your sugarhouse looking to expand your number of taps.

20) Stay tuned for 2023 – our 3rd year of ACER-funded research investigating alternative maple species production potential.