Progress report for FNE24-083
Project Information
We wanted to:
- Understand the nutrition underlying 2023 animal enthusiasm about our SARE FNE22-013 field-edge tree/shrub leaf-silages, plus explore additional tree/shrub species including those deemed “invasive;”
- Explore why my animals limit their consumption of regionally abundant Red (and Sugar) Maple leaves, and contribute data to limited scientific understanding of toxicities present in maple species; and
- Delineate safe use of Black Cherry (and also some Pin Cherry) per Hydrogen Cyanide levels - Black Cherry grows substantially along field edges, and was a livestock top choice.
Dairy One (Ithaca, NY) completed nutritional analyses on 94 leaf-samples of 17 tree and 9 shrub species so far, including 20 matched fresh/ensiled sample-pairs to look at nutritional changes when ensiled. We ordered quantification of Soluble Protein (SP) and Rumen-Degradable Protein (RDP), with partial success (many of those tests failed), to gain clues about protein utilization.
High energy/low fiber traits of tree leaves were confirmed: our leaf-silage averaged 120% of the Water Soluble Carbohydrate level (WSC) of Dairy One average grass-silage, and over twice as much Non-Fiber Carbohdrates (NFC) overall.
Harvest-date comparisons are confounded by differing quality of 3 sites (see 2 “Harvest-date” spreadsheets under “Results”).
We had Dairy One analyse 4 long-fermented leaf-silage samples for 6 acids normal to grass and corn silage, as follow-up to 2019 short (<1 yr) Fermentation Profiles which showed almost no such activity (see “Fermentation” spreadsheet under “Results”).
We also added analyses of fats (Fat Ether Extract = Fat EE) and Ash, in order to obtain accurate NFC figures; average leaf-silage Fat content was 147% of the average Dairy One grass silage figure, and averaged 111% of levels in matched fresh leaf-samples (see “All” and ”Paired” spreadsheets under “Results”).
Cherry leaves become much safer when ensiled. We will continue testing for Hydrogen Cyanide in 2025. Toxins in Maples, Box Elder and Sumac vary widely per tree or site; I wil lfollow up in 2025 with an added plan of date-varied acceptance/refusal triling with my steer and goats. Box Elder has the highest known safety risk.
Once web-related tasks/expenses are completed, Tech Advisor Karl Hallen and I will decide which further sampling and analyses will fit in last bits of our budget. Our wish-list goes beyod funds: new matched fresh/ensiled sample-pairs of species missed, harvest-date comparison of fresh samples of 3 species each harvested at 3 different dates from same sites, and lipidomic work to determine identity and dietary value of our high Fat EE levels.
Since start of this project 6 months ago, I’ve given 9 presentations at 5 event venues, and tabled twice. Venues beyond Maine were NOFA MA “Go Nuts” on-line agroforestry discussion series, and the intermational Short Rotation Woody Crops Conference at University of Missouri Center for Agroforestry, both in May (unfortunately, trips away are no longer possible, due to goat behavior). A second Poor Proles Almanac podcast interview, this time about results of these SARE projects, has been recorded, and will air this coming summer. In person, farmers can join me for a willow silage harvest at MOFGA Farm & Homestead Day next June, or find me at the Common Ground Fair in September.
See https://3streamsfarmbelfastme.blogspot.com for various spreadsheets, presentation recordings, and slide PDFs with full text. See "Results" below, and "Informational Productss" above, for those completed since commencement of this study.
This project seeks to seize an opportunity for optimal data collection from SARE FNE22-013’s vast tree/shrub-leaf fresh-sample and silage “bank” collected in 2023 plus additional samples, and improve/use web-based outreach, to bridge an informational gap that is slowing livestock farmers from
productive use of on-site woody perennial forages when weather challenges interfere with their grass-forage harvests.
We will:
- Broaden analyses of nutrition, ensilement and digestibility to 28 tree/shrub species including 6 “invasives” for generalizable findings on ensilement plus per-species info sought by Northeastern farmers;
- Broaden toxin testing with ensiled comparisons to 2 cherry and 5 maple species plus sumac, sampling a range of harvest dates, wiltedness, and ensilement time-periods, to minimize farmer and livestock risk in using these high-yielding species common to field edges;
- Obtain triplicate analyses for 7 silage species fed during upcoming winter goat/steer and cow dietary intake/milking trials, to encourage further study by meeting academic standards, while also increasing confidence for farmer recommendations; and
- Update, improve and use our website, listserv, and network to organizations/other sites serving farmers, to streamline provision of this critical alternative forage data.
Northeastern farmers can then effectively supplement ruminant rations with vital on-farm forages.
Northeastern farmers’ climate risks around grass-based forage continue. In 2023, water-logged fields caused a first-harvest hay-scramble in mid-August. Nutritional quality of such late first-cut is poor, and second-cut was low in volume. Grass baleage provided to Meadowsweet Farm was also cut late; farmer Eliot VanPeski said his grass-fed cattle were in less good condition due to poor silage quality.
Cattle browse-lines are evident on field-edge trees of most Northeastern dairy farms. Tech Advisor Karl Hallen observed in his past herd that his highest-performing cattle were doing most of that browsing; Fred Provenza (Pershouse & Perovenza 2020) stated that ruminants perform better across the board with access to woody browse . Tree/shrub leaf-silage can extend both known and (humanly) unknown benefits into ruminant winter diets.
Our weather-resilient SARE FNE 22-013 harvest of field-edge trees and shrubs started as soon as Doak’s Machine finished upgrades on the Chain-Flail Leaf-Separator prototype in late June, and yielded slowly but plentifully. Cutting with hand-held power-tools, and stripping leaves with this machine prototype (created by current Tech Advisor Karl Hallen) which is 90% quicker than traditional hand-stripping, we produced 2,500+ gallons of tree/shrub leaf silage (70 of 60-70 planned barrels) in only 1,000 lineal feet of field edges (our proposal identified 5,700 LFT for potential harvest).
Cattle generlly eat 12% Dry Matter (DM) of woody browse, sheep 20% and goats 60% (Whistance 2021); my steer Angelo in SARE FNE22-013, with unlimited access to that low-quality 2023 late-cut hay, consistently chose tree/shrub leaf-silage as 33% DM of his (grain-free, forage only) diet across three separate 11-day periods of one 2 hour offering-period/day. Angelo kicked up his heels to gallop to it (he only trotted quickly for the alternate-period offerings of 2nd-cut hay); I did not weigh him, but he outgrew draft tack and looked great all winter.
Positive livestock palatability responses from SARE FNE18-897 and VTGF mini-grant nutritionl results (Hanson 2020 b) preceded SARE FNE22-013 data on HOW MUCH my steer and goats will eat, and on whether leaf-silage can support milk production (it does, though low protein availability can be a limiting factor if not supplemented). Our overlapping current project uses fresh and ensiled leaf-samples taken during FNE22-013 harvests and winter livestock trials, plus additional new leaf-sampling, to explore nutritional levels (more thoroughly than in previous VTGF study), nutritional changes when ensiled, reductions in cherry-leaf Hydrogen Cyanide toxin-levels when ensiled, plus add to sparse information on toxicities present in maple species.
We are taking opportunities to go beyond committed testing. Wayne Zeller, US Dairy Forage Research Center, will receive freeze-dried samples from us soon, to isolate and identify Condensed Tannins from 17 to 20 of our species screened to have high levels.
This project also funds changes to/improvement of our web presence, where farmers can access this new information and other resources on use of tree/shrub forages.
I have summarized all data to date on printable spreadsheet pdfs (see “Results” section) and in presentations, highlighting noteworthy trends, remaining limitations of our data-set, and new insights plus unanswered queries, for both farmers rationing leaf-silages, and researchers interested in benefits to ruminants.
As yet, other farmers do not have leaf-separator machines, but some are proceeding to use tree/shrub forages fresh, dried, chipped or hand-stripped. They are eager for our new information at my presentations; that information is updated and more completely offered herein under “Results.” It’s already helping these smallest most flexible and adventuresome farmers accurately and safely plan winter diets for their herds. My summer of immersion in data has increased my own critical understanding, to improve how I feed my herd.
I look forward to: loads of leaf-silage for winter abundance and optimal animal health on my own farm; sharing machinery and experience with other farmers as they achieve much-needed forage-security and ongoing productivity; and researcher contributions to what my animals already seem to know about our Northeastern tree/shrub resources. I hope my efforts support long-term increases in farm-scape diversity, full of trees with useful accessible canopies, pleasantly moderating farm temperatures, winds and rain. I hope also that tree-based industries soon find added-value encouragement of new forage-streams, that can strengthen sustainable, renewable land practices.
CITATIONS:
Whistance, Lindsay. Farming, Animals and Trees. In Tree Fodder Virtual Seminar webinar hosted by Steve Gabriel, Wellspring Forest Farm, December 10, 2021. Accessed 1/20/25. https://www.youtube.com/watch?v=hCJYKhOZt58&list=PL3dng73x0WAQKUQKFWM12Ky2DkHgub7rt&index=4
Pershouse, Didi & Provenza, Fred (2020). Nourishment: Learning from the Nutritional Wisdom of Grazing Animals. Webinar “Mini-Course” 5/21/20, hosted by Land & Leadership Institute.
I farm full-time at 3 Streams Farm (my home since 2000) and Belfast Blueberry Cooperative (field purchased in 2018) bringing (9 right now) dairy goats and a steer both places, and have history of longtime professional winter orchard-pruning (starting in 1983). After 8 years of goat observations, I started working with tree fodders as a primary focus in 2011, presenting internationally at 2iem Colloque Trognes in 2018. My SARE FNE18-897 and 2019 VTGF projects broke ground on tree-leaf storage, palatability, and nutrition of Northestern US tree leaves, and I am currently leading SARE FNE22-013, almost complete, which funded the Chain-Flail Leaf-Separator prototype made by Karl Hallen (Tech Advisor for FNE24-083 to which this report pertains). That project and machine enabled production of enough leaf-silage for a 60-day home livestock trial with my very willing steer and 10 goats, plus three shorter trials at other farms, and was the source of most (but not all) samples tested for this overlapping, ongoing FNE24-083 project.
3 Streams Farm provides goats’ milk from 100% fresh greenery of woodland and pasture, to seasonal subscribers. Belfast Blueberry Cooperative provides fresh-market wholesale and PYO Certified Organic blueberries each late July-August. Combined gross is $12-$15,000.
Cooperators
- - Technical Advisor
Research
1. Broaden analyses of nutrition, ensilement and digestibility to 28 tree/shrub species including 6 “invasives:”
Send 1 fresh-frozen and one ensiled sample per species, of machine-separated
tree leaves:
American Beech, American Basswood, American Elm, Big-toothed Aspen, Quaking Aspen, Black Cherry, Pin Cherry, Black Locust, Box Elder, Gray Birch, White Birch, Green Ash, White Ash, Hybrid (Crack/White) Willow, Norway Maple, Red Maple, Rock Maple, Striped Maple, Red Oak,
and shrub leaves:
Arrowwood, Autumn Olive, Pagoda Dogwood, Honeysuckle, Leatherwood, Multi-flora Rose, Smooth Buckthorn, Stghorn Sumac, Winterberry (I also added a hand-stripped sample of Bittersweet; I will try next summer to machine-separate some, now that new enlarged sprockets can grip small stock).
Data is complete on 19 fresh/ensiled species-pairs (plus a second White Ash pair), and one sample either fresh or ensiled of 7 other species (see spreadsheets under “Results” below). I’ve not yet tested three species at all: Hybrid Willow we just harvested in October 2024, due to deliberation about 2022 PFAS result; Pagoda Dogwood Susan Littlefield took samples, then misplaced; and Susan and I mislabelled some birch as “White” which was not.
I will pursue missed sampling in summer 2025, as in 2024 too much time was spent inventorying and pulling frozen samples to send, processing and re-processing data as results came in, and preparing presentations for 5 venues. I am painstakingly slow but persistent on the computer (light-sensitive eyes, swollen hands excerbated by sorting frozen samples in an unheated open-air basement, intermittent typing on browse walks in summer, computer-charging failures in winter). I continue to learn spreadsheet processes and shortcuts by trial and error – this learning is an exciting and worthwhile outcome.
to DairyOne for:
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“Ration Balancer” analysis which includes Moisture Content (MC), Dry Matter (DM), Crude Protein (CP), Acid Detergent Fiber (ADF), Neutral Detergent Fiber (NDF), Non-Fiber Carbohydrates (NFC), Total Dietary Nutrition (TDN), Net Energy for Lactation (NEL), Net Energy for Maintenance (NEM), Net Energy for Growth (NEG), Relative Feed Value (RFV) and 11 minerals, and
We learned partway through that previous Relative Feed Value (RFV) and Non-Fiber Carbohydrate (NFC) figures were inaccurate due to lab categorizing of samples as grass forages; these were missing when Dairy One started correctly categorizing. So mid-stream I started ordering/paying for Fat EE and Ash add-ons in order for Dairy One to compute accurate NFC results (NFC though listed in initial package is included for grass forages only, as they use average known grass Fat and Ash figures).
RFV is a computation from Acid Detergent Fiber (ADF) and Neutral Detergent Fiber (NDF); Dairy One sent me a calculator spreadsheet containing the formula, and I replaced missing RFV figures.
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Add-on measurements of Water-Soluble Carbohydrates (WSC), Soluble Protein (SP), Rumen-Degradable Protein (RDP), and Ph.
Water-Soluble Carbohydrates (WSC) results are complete for all samples analysed so far, and are a valuable highlight of leaf-silages (see spreadsheets under “Results”).
Dairy One gently requested for us to stop ordering Soluble Protein % DM (SP) and Rumen-Degradable Protein % DM (RDP) tests, as in many, the required liquid preparation gelled up and clogged their filter.
For each ensiled sample, also obtain analysis of
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Ammonia.
See “Results” for Ammonia figures on samples completed. ALSO we re-allocated funds to obtain 4 “Fermentation Profiles” on samples ensiled more than 1 year, as follow-up to information from my 2020 VTGF Mini-Grant report on first-winter leaf-silages, of very low or zero amounts of the usual 6 acids found in grass and corn silages. These acids did appear with longer ensilement.
***See “Fermentation Profiles” spreadsheet and Fermentation discussion in “Results” section below.***
a. Chart data per 28 species; (All data so far is organized on spreadsheets, in “Results” section.)
b. Compute mean and range of each nutritional measurement across species;
***See “Nutritionl Data from All”spreadsheet.***)
c. Compute mean and range of changes in each nutritional measurement from fresh to ensiled, across species;
***See “Paired Fresh & Ensiled” spreadsheet.***
c. Re-grouped Fresh/Ensiled Pairs into 3 harvest-date categories. Computed mean and range of changes in each nutritional measurement from fresh to ensiled, per date category, to look at effects of length of period ensiled (but even these changes are affected by date-related differences in initial fresh leaf carbohydrates especially). I also compiled fresh and ensiled data separately per date-period, on same sheet, to look for date differences attributable to leaf development of fresh samples, and to have allow others to puzzle over the complete data-set.
On separte spreadsheet, I re-grouped selected data of 3 species having multiple harvest-dates, into 3 harvest date-periods. I noted trends of change for each nutritional measurement as leaves matured and changed, while length of remaining warm weather-period supporting fermentation decreased.
Both of the above harvest-date category spreadsheets looking simultaneously at these two factors can help farmers to think about their choice of dates to harvest/ensile leaves, but do not offer conclusive results due to differing richness of our 3 sites, with each site harvested at a different point in the growing season.
I plan to obtain and test 2025 fresh samples of 3 species repeating same sites at 3 harvest-dates, for nutritionl effects of leaf development only. Our paired samples already give a good look at nutritional effects of ensilement.
***See “Fresh/Ensiled Pairs Comparing 3 Date Categories” spreadsheet, & “Selected Leaf-samples Comparing 3 Date Categories” spreadsheet, both under “Results.”***
d. Discuss protein availability in light of CP, SP, RDP and Ammonia measurements, including change from ensiling. (See Protein discussion under “Results.” I continue to consult and read about this complex subject, which Karl Hallen and Juan Alvez try to explain to me. Additionally, Wayne Zeller’s Condensed Tannin – CT – results will play into our understanding of protein utilization.)
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Offer charts plus summarize findings in our Final Report, to give farmers:
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Generalizable information on effects of ensilement on tree/shrub leaf nutrition, including information on protein availability (important for animal growth or lactation, versus traditional winter maintenance), and changes in sugars (WSC) and Ph (which both affect rumen function and silage shelf-life), plus
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Per-species nutritional info for most common tree/shrub species at Northeastern field-edges (including 2 tree and 4 shrub species designated “invasive”).
***Charts are useable now. Find them in the “Results” section.***
A bit more data will be added next summer, 2025.
2. Broaden toxin testing with ensiled comparisons:
Use existing fresh-frozen/ensiled sample-pairs (for immediate March 2024 results), plus harvest, machine leaf-separate and pack new samples, and obtain laboratory analyses for:
a. Hydrogen-Cyanide (HC or Prussic Acid) in 17 cherry leaf-samples:
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6/27/23 Black Cherry (MOFGA), Ensiled 120 days then frozen;
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6/29/23 Pin Cherry (MOFGA), 1 Fresh-frozen/1 Ensiled 120 days then frozen;
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10//23 coppiced Black Cherry (Y Knot Farm), left out 24 hrs on a gray day, 1 Fresh-frozen/1 Ensiled 30 days then frozen;
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4 samples early June 2024 Black Cherry from Y Knot Farm, Fresh/Same Ensiled 30 days, 60 days and 90 days;
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4 samples early June 2024 Black Cherry from Y Knot Farm, Wilted 4 hrs (mid-day in full sun, before leaf-separation)/Same Ensiled 30 days, 60 days and 90 days;
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4 samples early June 2024 Black Cherry from Y Knot Farm, Wilted 24 hrs (branches cut then left out overnight across parts of two sunny days before leaf-separation)/Same Ensiled 30 days, 60 days and 90 days;
Summarize findings with recommendations/warnings for safe use of ensiled cherry leaves.
Tests on 3 pairs of samples (in above 1st 3 bullets) are complete, and showed very safe reduction of Hydrogen Cyanide with ensiling. Even fresh levels were below the toxic threshold. See “Cherry Leaves & Cyanide” spreadsheet under “Results.”
I will re-sample in June 2025 for rest of testing commitments; I have all 2024 samples frozen, but new Ziploc bags with differing texture (used doubled) apparently leaked, as evidenced by fungi in ensiled samples. So highly volatile HC probably escaped; therefore I did not send this 2024 sample-set for testing, but instead will re-do with screw-top containment in 2025.
b. Gallic Acid and Ellagic Acid both free and total=hydrolyzed, Hypoglycines A and B, plus related Methylenecyclpropylglycine (MCPrG) and γ-glutamyl-MCPrG levels in 1 Fresh/Ensiled sample-pair each of 6 species (Difference between free and hydrolyzed Gallic Acid will give sum level of complexes such as Gallotannin which contain Gallic Acid):
Red Maple, Rock Maple, (Striped Maple we took out, but will include in livestock sampling), Norway Maple, Box Elder, and Sumac.
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Compare 6 toxin levels between above species,
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Explore relationship to ruminant intake data from SARE FNE22-013 livestock trials plus additionl sampling/feeding observations in 2024-’25,
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Continue to review literature on this obscure subect;
Due to misunderstanding of listed gallotannin lab-service at UC Davis, which was non-quantitative and only on horse urine, we re-allocated funds for 3x greater expense of higher-tech analyses at MU Metabolomics Center. There, they quantified Gallic Acid (GA) and Ellagic Acid (EA) both free and total = hydrolyzed* (EA added on advice of Director Zhentian Lei), and relatively quantified Hypoglycines A and B, plus related Methylenecyclpropylglycine (MCPrG) and γ-glutamyl-MCPrG (due to literature search, we added these 4 maple-species toxins), in 3 fresh-leaf replicates each of Red Maple, Sugar Maple, Norway Maple, Box Elder, and Staghorn Sumac (Zhentian Lei strongly recommended 3 replicates= similar individuals of each species, so due to limited budget we left out less abundant Striped Maple and ensiled comparisons).
*11 of 15 free GA figures are much higher than total= hydrolyzed figures. Zhentian Lei responded that some Free GA is lost during hydrolysis, So it seems that hydrolysed= Remaining GA versus Total. I await answers as to whether this data still gives clues about levels of complex forms of GA such as Gallotannin.
***See “Maple, Box Elder & Sumac Toxins” group of files under “Results.”***
Report findings on:
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Limitations/dangers of ruminant intake per tree species re: these 6 toxins,
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Potential ruminant digestive benefits related to Gallic and Ellagic Acids,
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Livestock fresh-fed preferences and rejections of these 4 Maples, Box Elder, nnd Staghorn Sumac at various harvest-dates in summer 2025.
These toxins are said to increase throughout the season. Our “straw-payer” at University of Missouri Center for Agroforestry expressed unwillingness to wait; hence our rather early June 24-25, 2024 sampling dates. (MU Metabolomics Center can only directly serve those with university and other official research organization accounts.)
I have changed the last bullet above to include a more thorough assessment of my own knowledgeable animals’ leaf rejection-dates. Most sampling will be near work at the blueberry field; I will see if friends in Unity will bring Box Elder on their trips into Belfast, and renew permission to cut Norway Maple at Y Knot Farm or downtown Belfast.
***See discussion & “MU Metabolomic" files under “Results,” for charts and graphs provided by Zhentian Lei, MU Metabolomics; I’ve typed minor additions. (I have not yet learned how to make computer graphs. There is at least one graph error to be corrected before Final Report). ***
3. Obtained 1 nutritional analysis per each tree/shrub-species layer or full barrel/bucket of leaf-silage (Black Cherry, Gray Birch, Honeysuckle, Quaking Aspen, Big-Toothed Aspen, Red Maple, Red Oak, White Ash, Green ash) fed during our 12-week winter SARE FNE22-013 goat/steer trial (which measured dietary intake and milk yield), plus obtained analyses on each other ensiled batch of those species, and on other less abundant tree/shrub species fed out during that trial plus trials at Y Knot and Faithful Venture Farms.
Took 3 lbs per numbered barrel fed, drawn from near top, middle and bottom of each barrel, then mixed/bagged/froze 2x1 qt and 2x tiny- bag (2”x3”) samples. We took/packed/froze lesser amounts from each bucket fed. Sent 1 or more sample/harvest-date/tree or shrub species for DairyOne analyses including:
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“Ration Balancer” analysis which includes Moisture Content (MC), Dry Matter (DM), Crude Protein (CP), Acid Detergent Fiber (ADF), Neutral Detergent Fiber (NDF), Non-Fiber Carbohydrates (NFC), Total Dietary Nutrition (TDN), Net Energy for Lactation (NEL), Net Energy for Maintenance (NEM), Net Energy for Growth (NEG), Relative Feed Value (RFV) and 11 minerals on most samples, and
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Add-on measurements of Water-Soluble Carbohydrates (WSC), Soluble Protein (SP), Rumen-Degradable Protein (RDP), Ammonia, and Ph.
Charted, examined and reporting: (See “All” spreadsheet in “Results” section)
a. Mean of each nutritional measurement per tree/shrub species; (Did)
b. Relationships between animal intake and nutritional measurements per tree/shrub species; (Do in 2025)
c. Nutritional comparison of these (mostly) 2023 leaf-silages to Dairy One average grass-hay and grass-silage figures 2004-2024, and to 2 samples of 2023 hay from 2 sources, that we fed out during the 3 Streams Farm trial. (Compared our hay to all; compared Dairy One averages to a partial list of nutritional measures; see “All” spreadsheet under “Results.”)
Based upon this data plus standard nutritionl requirements and data from “1.” above:
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Offer supplemental leaf-silage rationing recommendations per ruminant species, including whole-diet examples with other feeds identified to fill nutritional gaps, if such remain; and
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Update SARE FNE22-013 cost/benefit analysis of this leaf-silage, to re-report in light of our new data and insights (simple example: costs of mineral supplements may be saved).
I will complete last 2 bullets for our Final Report next year.
4. Update, improve and use our website, “tree fodder” listserve, and network of livestock farm-related organizations and sites,* to streamline provision of this critical alternative forage data, augmenting in-person presentations at farmer events.
Emily MacGibeny re-organized my past reports and presentations on our current website, and did significant work on a new “wix” website (which platform she prefers to our “blogspot), but became unavailable last spring, and then resigned this winter. My housemate Merissa MacDonald, Consulting Arborist and Grant Writer for Hyphae Design Laboratory, hopes to pick up where Emily left off, but has little time to do so. Bailey __ video-recorded the 2024 leaf-separator demo at Common Ground Fair and is editing for me in trade for milk. This and 2 other recorded presentations have yet to be posted for farmers.
I will continue to pursue completion of these web tasks through these or other helpers (photosensitive eyes make computer work slow and painful, or impossible, to do myself).
NUTRITIONAL ANALYSES
Dairy One (Ithaca, NY) completed nutritional analyses on 94 leaf-samples of 17 tree and 9 shrub species so far. I organized results by species, with fresh-frozen versus ensiled paired samples listed at top of each species-specific list, and following samples organized consecutively by harvest-date. A later harvest-date= shorter ensilement; we froze most ensiled samples during 2023-’24 winter feed-out, including those harvested in fall of 2022 when our Leaf-Separator machine first arrived (therefore the 2022 barrels and buckets had the longest ensilement period, with a few warm-enough fall weeks plus one full summer).
Species averages of each nutritional measure (using ensiled samples only, as fresh/ensiled paired samples repeat the same batch) are below species-specific lists containing multiple batches, and averages of 10 most abundant species are also compiled and averaged across species on last pages 11-12 of “Dairy One NUTRITIONAL DATA from ALL 2022-'24 LEAF-SAMPLES analysed” spreadsheet PDF below.
For Species averages, go to END (pp11-12) of: Dairy One NUTRITIONAL DATA from ALL 2022-'24 LEAF-SAMPLES analysed
(formatted to print on legal-sized, landscape-oriented paper.)
These results are specific to our 3 Waldo County, Maine harvest-sites, with varying and sometimes low numbers of samples per species. Harvest was aimed at yield measurements and provision of many whole barrels for livestock trials in SARE FNE22-013. Validity of comparisons of species averages is limited by differing site qualities and differing harvest date-windows at the sites (the Leaf-Separator machine farm-trailer base requires slow transport-speed, so was parked at sites consecutively with just one return-trip to Y Knot Farm.) We generally harvested in linear field-edge order, at each site.
Dry Matter in our leaf-silages averaged 44%.
Protein: Crude Protein (CP) levels in our leaf-silages were respectable, falling between those of the 1st- and 2nd-cut hay we had that winter. Early cuts of both grass and tree matter are known to have higher protein levels than later cuts. 1st- and 2nd-cut hays were both cut in late August, due to 2023 wet June and July; the bulk of our leaf-silages we harvested late June through July, and then a lesser number of barrels late September through to October 12th.
Acid Detergent Insoluble Protein (ADICP) levels in my 2019 leaf analyses indicated limited protein availability, as do our new results. We therefore ordered quantification of Soluble Protein %CP (SP) and Rumen-Degradable Protein %CP (RDP), to gain more clues about protein utilization. In many of these tests, the required liquid preparation gelled up and clogged a filter. After the first large batches of samples yielded much but not all requested data, I gave in to Dairy One’s gentle suggestion for us to stop ordering SP and RDP tests.
We have complete SP and RDP data for all samples of 16 species (out of 26). SP and RDP tests failures happened on all 5 Red Oak samples, and on fresh/ensiled sample-pairs of American Elm, Norway Maple, and Smooth Buckthorn, such that we have no measurements for these 4 species. Either SP or RDP failed on 4 out of 5 Honeysuckle samples; RDP failed on 4 out of 7 Quaking Aspen samples, 1 of 6 White Ash samples, and 3 of 11 Black Cherry samples. All of the first 3 SP tests and 2 of the first 3 RDP tests failed on Gray Birch, such that we have no SP and only one (curiously high) RDP result on Gray Birch (so we stopped ordering these tests on Gray Birch); Red Maple had this problem for SP and RDP on 64% of tests.
From SP %CP, RDP %CP and CP %DM, I computed SP %DM and RDP %DM for both leaf- and grass-forages, to compare actual quantities in the feed. SP levels in our Black Cherry and Green Ash samples were highest, and matched or surpassed the level in our 1st-cut hay, as did some levels in White Ash. RDP levels were also highest in these species, but lower than that of the 1st-cut hay.
Jaime Garzon,UME Cooperative Extension Forage Specialist, uses a practical guideline that WSC to CP ratio should fall between .4 and 1.5 in silage, for digestive balance (personal communication 12/2/24). Of that CP, he says SP should be 30-40%. Our average Black Cherry silage falls well within that WSC/CP range at .65, but with SP at only 20% of CP. Our Green Ash ratio is .575 with SP at 22%.
Acid Detergent & Neutral Detergent Fiber was much lower in our leaf-silages than in grass forages.
Non-Fiber Carbohydrates (NFC): Our leaf-silage had around twice the NFC of Dairy One average grass-silage, and nearly matched average grass-silage level of Water-Soluble Carbohydrates (WSC).
Fat Ether Extract level in our leaf-silages averaged 6% DM, or 150% of that in average Dairy One grass-silage.
Hauge, Garmo & Austad wrote (pp 74-75 in Austad & Hauge 2014) (my English notes from the Norwegian – thank you to Yvonne Taylor, past Black Locust Farm farmer, for translating to me a few years ago) :
“The fat content is high in leaves (5 – 7% DM), like (as compared to?) grass (1 – 3%).The reason is that the leaves have a thick, protective [layer?]. This layer serves as a defense against parasites, and reduces water loss as a result of transpiration in the plants. The outermost layer (cuticle) is built from a cutin and wax that doesn’t have any nutritional value. Leaves from birch often have a higher content of fat than leaves from willow, vier, or, aspen, and rowan. The least fat content is found in elm, ash, linden, and hazel. Like in grass and clover (trifolium species) it is [linolensyren = Linolenic acid = ALA acc to Google] that is most prevalent in leaves (35 – 45% of total fatty acids) (Garmo 2012).”
In light of this, our leaves should have around 2.4% DM Alpha-Linolenic Acid.
Ensiled leaves consistently had more fat than fresh leaves (averaging 111% of fresh level). Perhaps the rise is in wax coatings, as the leaves suffocate? Or do the wax coatings break down to become digestible fats?
Minerals varied widely in our leaf-silages, as did those in my 2019 samples. Our species-averages of Calcium were high, ranging from similar to levels in both our hay samples, to almost 3x as much as in the hay. Note also that our 2nd-cut hay was full of dirt, with minerals that my animals did not eat (our leaf-silages include no dirt).
Net Energy in our leaf-silage averaged scores of 66 for Lactation, 64 for Maintenance, and 38 for Growth. These were higher than in either of our hay samples (not sure why Angelo seemed to grow).
Fermentation & pH: In 2019 I was confused by low 3.7 pH of spring-harvested Beech leaf-silage with almost no fermentation acids detected in any of 5 samples tested. I thought that perhaps different acids were produced (but possibly that acidity was from Vitamin C, already present when leaves were fresh?). So we decided last summer to send 4 samples ensiled for more than a year; the usual fermenttion acids did appear. PH went down from fresh to long-ensiled (over 1 year) 1.1 points in Big Toothed Aspen (going from 5.5 to 4.4), zero in July-harvested Beech (which stayed at 5.4 with very low .4% total acids), and 1.5 in Winterberry (going from 5.7 down to 4.2, the acceptable upper limit for grass silage. In first winter, pH was 5.4). Across these three sample-pairs, fresh pH averaged 5.53, and 1+year ensiled pH averaged 4.67.
The animals consistently mobbed our pleasant-smelling 1+ year-old leaf-silages of palatable species and ate them, as they did in the first winter.
***See “Dairy One NUTRITIONAL DATA from ALL 2022-'24 LEAF-SAMPLES analysed” & “Dairy One FERMENTATION PROFILES & Nutrition, comparing 2018…” spreadsheet PDFs below, both formatted to print on legal-sized, landscape-oriented paper.
Dairy One NUTRITIONAL DATA from ALL 2022-'24 LEAF-SAMPLES analysed
Nutritional Changes from Fresh to Ensiled
We’ve completed 20 matched fresh/ensiled sample-pairs of 19 species (two of White Ash, with much healthier-looking leaves from the site with later harvest-date, hence duplication) to look at nutritional changes when ensiled.
Dry Matter (DM) decreased slightly with ensilement, while %DM of both types of fiber (Acid Detergent and Neutral Detergent) went slightly up, as did %DM of Crude Protein (CP). Within CP, Rumen-Degradable Protein %DM (RDP) decreased to 95% of Fresh average, which indicates that the increase in CP consisted of rumen-escaping protected proteins. Within decreasing RDP, Soluble Protein %DM (SP) increased to 103% of the Fresh average. So Rumen-Degradable Insoluble Protein was what decreased, as CP went up as a whole with more rumen-protected protein plus more soluble protein. (I realize I am be-laboring this, and also that my use of SP %DM versus %CP is unconventional, but I am trying to visualize complexity of the changing amounts).
Water-Soluble Carbohydrates (WSC) dropped 36% of fresh level when ensiled, though Non-Fiber carbohydrates as a whole only dropped slightly (so did starches increase? We did not test for these). Fat Ether Extract went up; fat content in ensiled samples averaged 111% of levels in matched fresh leaf-samples. This rise of Fat when leaves are ensiled, consistent across samples, intrigues me; tree physiologist Kevin Smith, UNH Extension, Durham (email 6/26/24), said that WSC can only be converted to fat in aerobic conditions (does it happen immediately upon sealing the barrel?)
*** See “Dairy One data comparing PAIRED FRESH & ENSILED leaf-samples” spreadsheet PDF, formatted to print on legal-sized, landscape-oriented paper.***
Dairy One data comparing PAIRED FRESH & ENSILED leaf-samples
Harvest Date Effects
I divided our Fresh/Ensiled sample-pairs into 3 harvest-date categories, to look at the interaction of said-to-be lower quality at later harvest-dates, and less warm weather left for fermentation for those harvested later as well. Noth these comparisons have limited validity due to differing harvest-sites per date-period,
(Spreadsheets below formatted to print on legal-sized, landscape-oriented paper.)
Dairy One PAIRED FRESH & ENSILED samples, HARVEST-DATE categories COMPARED
Selected leaf-samples comparing 3 HARVEST-DATE categories
TOXIN ANALYSES
Hydrogen Cyanide in Cherry Leaves
Tests on 3 fresh & ensiled sample-pairs are complete, and showed very safe reduction of Hydrogen Cyanide with ensiling. Even fresh levels were below the toxic threshold.
I will add data re: early-cut cherry thought to be more toxic, and same with varying wiltedness and ensilement time-periods, once 2025 analyses are complete.
*** See printable copy: “Cyanide in Cherry Leaves” spreadsheet PDF below.***
Hydrogen Cyanide in Cherry Leaves, 4 Fresh & Ensiled Sample-Pairs
Gallic, Ellagic, & 4 non-proteinogenic Amino, Acid Toxins in Maples, Box Elder & Staghorn Sumac
A goat at Locust Grove Woodworks (Unity, ME) died a few years ago of bloat from Box Elder, when fed in a stall with limited choices. Box Elder from a sunny roadside site on Hunt Rd, Unity, was eaten without issue by my steer and goats at June 25th, 2024 time of sampling for metabolomics work, but was entirely refused when harvested from a pollarded tree at MOFGA South Orchard later in the season on July 20, 2024. Was that refusal due to the date, or the tree? The Kitchen Box Elder (also pollarded) at MOFGA had a 2x+ greater spike of Hypoglycine B than our other 2 samples.
As noted in Westermann (2016), toxin levels can vary greatly from tree to tree or site to site. Our species with highest spikes of HGA, HGB and γ-glutamyl-MCPrG each had broadly ranging levels among (3) same-species, same-day samples. Hence my animals will browse individual trees selectively. Their discernment is much more affordable than metabolomic analyses, but sometimes they aren’t present for my forage harvest. Scandinavian farmers of antiquity were said to taste tree leaves themselves, to know when to cut. Short of that skill, I proceed to report comparison of the averages.
By Final Report time next year, I hope to be able to discuss potential effects of measured levels (GA & EA) on the animals (quantification of the other toxins was relative, not measured).
In Box Elder, metabolomic analysis showed spike averages of Hypoglycin B (HGB) and of related γ-glutamyl-MCPrG to be drastically higher than in the other species, with the HGB much higher than any other toxin analysed. Box Elder was 2nd highest in HGA , but lower in related Methylenecyclpropylglycine (MCPrG) than all other species tested.
Red Maple leaves are used by my livestock if eaten alternately with other forages over time (in the SARE FNE22-013 trial, they finished leaves overnight, and also ate the twigs). Yet winter twigs and bark are an immediately-consumed staple for us. When I have brought home Sugar Maple, animal response has been similar (but with slightly less choice twigs and bark).
Red Maple leaf results show (Free*) Gallic Acid (GA) and Methylenecyclpropylglycine (MCPrG – related to Hypoglycine A) to have much higher spike averages than in the other species tested. All species tested showed HGA; Red Maple had the 2nd lowest level (Norway Maple had the lowest).
*A discrepancy seemed to exist in the Free and Total (=hydrolysed, including free GA plus GA in more complex molecules such as toxic hydrolyzable Gallotannin) GA figures. Ellagic acid (EA) figures less strongly had the same issue.
Zhentian Lei explained (1/16/25 email): “ The hydrolyzable data (hydrolyzable gallic acid and hydrolyzable ellagic acid) contain the free data. Because the hydrolysis was performed at high temperatures in strong acid, some free gallic acid could be lost due to degradation. Thus, the free gallic acid is a better indicator of its content in the samples while hydrolyzable ellagic is a better indicator of ellagic content in the samples.”
In Sugar Maple those 2 toxins in Red Maple were contrastingly low, while Hydrolyzed Ellagic Acid and Hypoglycine A averaged to be much higher in Sugar Maple than in other species.
It is interesting that Hypoglycin A (HGA) showed a much higher spike in our Sugar Maple leaves than in those of Box Elder, and (homologue of HGA) Methylenecyclpropylglycine (MCPrG) showed a much higher spike in our Red Maple leaves than in those of Box Elder.
El-Khatib et al. (2022) wrote that Hypoglycine B (HGB) and its homologue γ-glutamyl-MCPrG had been found in Sycamore seeds 50 years before, but were subsequently overlooked until their 2022 study, while HGA was assumed to be the cause of poisoning.
Norway Maple is a highly edible fodder tree from Europe, with leaves that my cattle and goats consistently devour. Our results confirmed low presence of toxins indicated by other researchers.
My goats strip bark and kill Striped Maple before it gets established here; I look forward to their responses on Striped Maple leaves from my blueberry property. Due to budgetary limitatiions, we did not include Striped maple in metabolomic analyses.
Staghorn Sumac is considered by Susan Littlefield to be a choice forage for her Y Knot Farm sheep; my goats refused senescing leaves but ate a few berries, in October (the only time we are near some).
Staghorn Sumac results showed second highest average Free* GA level (well behind Red maple), but way higher Hydrolyzed GA average than had Red Maple. *Zhentian Lei had labelled this column “Gallic acid” without specifying Free or Hydrolyzed, but he said he had only assessed Free at that point.
***See also “MU Metabolomics Charts & Graphs” below, created by them (with small changes typed by me), plus printable Legal/Landscape-oriented copy of above spreadsheet.***
MU Metabolomics Charts & Graphs,, with Hydrolyzed Gallic Acid added
MU Metabolomic Results spreaadsheet, inc Hydrolyzed Gallic Acid
CONDENSED TANNIN SCREENS & PLANS for IDENTIFICATION
Condensed Tannins (CTs)) are sought-fter in ruminant diets to improve utilzation of proteins, protecting them to pass through the rumen and be more effectively digested in the small intestine. There are also research indications that CT reduces ruminant methane emissions by changing rumen microbial populations, and probable negative effects for unwanted intestinal parasites.
Wayne Zeller, US Dairy Forage Research Center in Madison, WI, screened tiny fresh (and one ensiled: Quaking Aspen) leaf-samples from our 2023 harvest. Soon he will start isolating and identifying tannins from larger samples of all species rating “5” or higher (he is right now screening some additionl species I just sent). (*All of this was/is above and beyond our SARE committed research plans.)
***See also “Wayne Zeller’s CTannin Screens, my slides & 3 of Wayne’s...NOFA MA,” below***
Wayne Zeller's C Tannin screens, my slides and 3 of Wayne's used in NOFA MA 2024
CITATIONS:
Austad, I. & Hauge, L. (2014). Trær og tradisjon. Bruk av lauvtrær i kulturlandscapet. (Trees and tradition: Use of leaf-trees in the cultural landscape.) Fagbokforlaget. ISBN: 978-82-11-01905-9.
Westermann CM, van Leeuwen R, van Raamsdonk LW, Mol HG (2016). Hypoglycin A Concentrations in Maple Tree Species in the Netherlands and the Occurrence of Atypical Myopathy in Horses . J Vet Intern Med. 2016 May;30(3):880-4. doi: 10.1111/jvim.13927. Epub 2016 Mar 20. PMID: 26995161; PMCID: PMC4913566.
El-Khatib, Ahmed H., Anna Maria Engel, and Stefan Weigel (2022). Co-Occurrence of Hypoglycin A and Hypoglycin B in Sycamore and Box Elder Maple Proved by LC-MS/MS and LC-HR-MS Toxins (Basel). 2022 Sep; 14(9): 608. Published online 2022 Sep 1. doi:10.3390/toxins14090608
We wanted to:
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Understand the nutrition behind 2023 animal enthusiasm about (all except one species of) our SARE FNE22-013 machine leaf-separated field-edge tree/shrub leaf-silages from three sites (see FNE22-013 reports for details on the machine that Karl Hallen made, yields, etc.), plus explore additional tree/shrub species including those deemed “choice” by my animals but considered “invasive.” We also wanted to detail and confirm or refute (now retired) Waldo County Extension Forage Specialist Rick Kersbergen’s assertion that nutrition is “all down-hill” from fresh to ensiled, with comparisons of matched samples.
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Explore:
why my steer and goats limit their consumption of regionally abundant Red (and Sugar) Maple leaves, but eagerly eat the twigs and bark in winter as a staple forage, and always devour fresh or ensiled Norway Maple leaves;
why they only tasted fresh, and completely refused wilted Box Elder (another Acer maple species, sometimes called “Ash-leafed Maple”) which I once brought from MOFGA (and why Kenneth Copp’s doe goat in Unity died of bloat from Box Elder fed in her stall);
and whether Staghorn Sumac which Susan Littlefield’s Y Knot Farm sheep love (but my goats do not browse except a few late berries, when we are near some in fall) has similar issues to maples - Karl Hallen had heard that Sumac also had Gallic Acid issues (Ann Lichtenwalner, UME Animal Science Laboratories, now retired, had told me that Gallic Acid was one known toxicity in Red Maple, with other factors less understood).
After sparse but fruitful literature-searching, we saw need to contribute new data to limited scientific understanding of multiple toxicities that may relate to our animals’ responses to leaves of these Maple, Box Elder, and Sumac species, and chose Metabolomic Analysis examining 6 suspected chemical compounds.
Toxins in these species are especially pertinent to industrial leaf-silage sourcing where the farmer is not present to choose species, and to farms where animals are enclosed with limited experience and choice of browse. Forage experts need to understand what the toxins are, and at what levels, in order to recommend safe rationing parameters for Maple and Sumc tree/shrub species.
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Delineate safe use of Black Cherry, and also test Pin Cherry, per Hydrogen Cyanide levels. Black Cherry grows substantially along field edges, and has been consistently a livestock top choice and sometimes staple forage for my own goats and cattle plus for Susan Littlefield’s Y Knot Farm sheep, when fed fresh, dried or ensiled.
Cherry leaves are said to be deadly when wilted; my animals and Susan’s sheep eagerly eat a lot of cherry, and limit their own consumption when wilted. Farmers with less experienced animals need regionally pertinent safety information before initiating forage use of Cherry.
In this 1st not-quite-a year, our study has made worthwhile progress:
Usable Northeastern Nutritional Data: With most results in and funds spent, and just a few tail ends to pursue in 2025, nutritional data is now sufficient to guide farmer rationing experimenttion with Northeastern leaf-silage.
Farmer Perceptions & Awareness of Toxins: Countless farmers have thought to incorrectly inform me not to use Cherry leaves, yet noone seems to know about dangers of feeding Box Elder. Our Cherry-leaf toxin data indicates that Cherry species can be safely included in leaf-silage harvests (I’ll add more detailed data in 2025). I hope that my discussion and metabolomic data regarding Box Elder draws farmer attention, to use Box Elder with caution, as poisoning symptoms are multiple and deadly (see ____).
My planned exploration of animal acceptance versus refusal-dates in 2025 may further clarify Box Elder and Staghorn Sumac limitations, and Maple preferences.
Value of Norway Maple Leaves: I hope that our metabolomic data comparing Maples, Box Elder and Staghorn Sumac will change attitudes about “invasive” Norway Maple, for farmers to start utilizing this low-toxin, “snappable” easily-harvested, choice fodder-tree.
Landscape Benefits & Ecological Services of Regenerative Shrub Harvest: Our nutritional data on other “invasive” plants, especially including Multiflora Rose whith surprised me by making it through the Leaf-Separator, and also especially including my ruminants’ 1st-choice summer staple Smooth Buckthorn, strongly supports an approach of direct rotational browsing and regenerative forage harvest, versus uprooting and herbicidal extermination of these species. I’ve observed shrub removal to create ongoing lack of green understory in woodlands here in Maine.
A pro-life approach to “invasive” plants creates optimal biodiverse leaf-coverage, for climate cooling and soil-carbon increase. Browsing is known to increase biodiversity (Meuret & Provensa 20__);. harvest cutting-cycles can do the same, supporting non-invasive “invasive” plant participation in multi-species plant communities (an already-frequent occurance; Theodoropolis _____).
Shrub species from origins with domestic ruminant history have through necessity developed hardy growth habits. These plants are among our most viable Northeastern shrub-forages, more able to co-exist when fenced with livestock than are other Northeastern shrubs.
Surprises & Questions: As often happens, our multiple streams of new leaf-forage data have turned up these aforementioned curious surprises:
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Fat content rising when ensiled;
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Tests which gelled up and failed to yield results, in what were possibly the highest digestible-protein samples;
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Completely different toxin profiles in Red Maple and Sugar Maple leaves, both edible but not choice;
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Zero screening rating of Condensed Tannins in White Ash, a highly tasty traditionally staple forage (we knew animals can eat more when tannins are low, but that is REALLY low!), while Black Locust scored 10 yet was as speedily consumed (and July-harvested Gray Birch at 7 was almost inedible).
What type of fat increases through ensilement, and is it beneficial? What is the nature of those proteins that cannot be tested? One farmer who bought goats from me in 2020 feeds a lot of Box Elder; does he have harvest-date observations to report? Will Gray Birch screen at lower CT levels in spring and fall, when the animals love to eat it? Are Black Locust CTs tastier than Gray Birch CTs? Or are those proteins that gell up causing the Gray Birch refusals? Black Locust did not gell up (but oak, which they also always eat, did gell). – Or is the shiny cutin and wax leaf-coating objectionable? (Gray Birch Fat EE is higher than average – is that due to this coating?)
We aren’t yet testing for vitamins, or Volatile Organic Compounds - VOCs fill leaf-silage barrels with tree aromas, and probably increase the shelf-life of our milk, among other benefits.
Strangely, other farmers feeding leaves get just as excited as me. Our results so far are substantial, and support continued leaf-silage use and learning. Though not easy, nor efficient (yet), it’s somehow right. There are Quality of Life aspects of multi-sensory awareness, hard to explain, but simple, like wind in the trees.
CITATIONS:
Meuret, Michel & Provenza, Fred D. (2015). When Art and Science Meet: Integrating Knowledge of French Herders with Science of Foraging Behavior. Rangeland Ecology & Management, 68/1, Jan., pp. 1-17.
Theodoropoulos, David I. (2003). Invasion Biology: Critique of A Pseudoscience. Avvar Books.
Learning Outcomes
Key areas of change:
Knowledge of tree/shrub-leaf nutrition, and safety/limitations/toxicities; attitude-shift that tree/shrub forage use may be worth pursuing;
Awareness that tree industries produce untapped forage resources, and that routine farm brush-clearing and ROW pruning can be forage harvests. (Skills of pollarding trees, or of using our Leaf-Separator, were also part of activities during our 2 overlapping SARE projects, but pertain more to FNE22-013 than to this FNE24-083.)
Details of awareness in particular that were raised:
Concentrated energy in tree/shrub leaves as compared to grass forages may reduce grain cost (Jason Tessier, Tessier Farm);
Leaf proteins that escape rumen fermentation may benefit cheese-making (Kaili Wardwell, Abraham’s Creamery);
Cherry leaves have little risk of Hydrogen-Cyanide toxins when ensiled (many farmers, including email conversation);
Box Elder leaves are dangerous to ruminants once fully mature;
Potential exists for mechanical improvements that can make leaf-silage available in quantity, and tree/shrub-leaf forage value supports such development.
Project Outcomes
I expect increased animal health and higher winter milk yields, as I am committed to providing a significant quantity of summer-harvested tree/shrub leaf-silage to my animals in winter, from now on. This will be in addition to longstanding habits of fresh winter cutting with animals yarded for the winter on-site (I provide red maple daily for twig browsing and bark stripping, young fir side-buds and some bark which they browse directly, plus intermittent fresh winter cutting of Hemlock, and a bit of White Cedar, which used to be a winter staple for us, but is looking thin since the 2015-’18 droughts).
The animals are so excited on days when they see I’ve brought out a barrel! (When my aanimals are happy, I’m happy!) So I am adding road access to our blueberry field and a tractor, to be able to use the Leaf-Separator on my own land (so far, harvests for the Leaf-Separator have been on other people’s land).
Due to protein data, in future I am going to try to purchase a higher proportion of 2nd-cut hay, as I used to do before droughts threatened supply. (I am committed to forage-only diets. Grass silage holds threat of listeria for small ruminants; my steer eats with the goats.) I also look forward to Karl and my plan to obtain data on early-cut tree/shrub leaf-forages this coming summer, as those may be richer in protein.
I have ongoing communication/consultation with 14 Maine farms where I have visited or will visit, to help them move toward more tree/shrub forage use. Two of them were Trial Farms for FNE22-013, and have both increased their use. The coming season should offer more to report. Also people from 2 out-of state farms caught me at the 2023 or ‘24 Fair for rope-climbing lessons; the first had put in significant dried leaf-forage when I saw him again in 2024 (no one but me has a Leaf-Separator yet so far as I know, to make silage easily. I'm working on that.).
Labor-intensity of harvest-cutting remains a primary limitation, to be addressed with further development of equipment plus collabortions with tree (inc field-biomass) industries to separate leaves from what they are already harvesting. Tech Advisor Karl Hallen has hopes to be able to personally work on screen-winnowing of biomass for leaf use in the next couple years; I will continue to improve and use the Chain-Flail Leaf-Separator he created.
I tried this fall and will try again to access funds for an improved manufacturable engineered replication of the Leaf-Separator, with added brush-processing features. The engineer and machinist needed more market demand for this forage 1st, and such demand seems hard to create for an as-yet unavailable or labor-intensive product (a circular chicken or egg dilemma).
Similarly forage researcher Juan Romero, UME, tells me he can access funds to research leaf-silage once it is available in significant quantity; that research might create market demand to support machine development, but first we need a plan for quantity (which requires machine development). Wayne Zeller who is doing our (un-planned) Condensed Tannin work is trying to interest other US Dairy Forage Research Center staff to do in-vitro digestibility studies with my remaining SARE FNE22-013, or new, leaf-silage samples. Protein utilization and methane emission reduction, both in light of tannin benefits, are hot topics currently.
I continue to want (or possibly plan) research of leaf lipids, to understand which go up when ensiled. I have a hunch that special digestive qualities of those fats may add animal enthusiasm beyond abundant minerals and high level of Non-Fiber Carbohydrates (quantifying sugars and fats). As with other forages, high ALA content in tree leves is known to offer healthful CLA in milk for humans. Such info can help support demand, to improve supply.
Grass-fed cattle farmers, and all goat farmers , can especially benefit from tree/shrub use, especially when climate challenges reduce quantity or quality of grass harvests. Northeastern farms will find our regionally limited data to be most pertinent to their farm resources, but some nutritional parameters may apply to broadleaf trees in general, and be of interest beyond our region . Mid-sized and larger farms need above developments to access and use leaf-silage. Small Northeastern farms, including most Maine goat and sheep farms, are already able to use our information to ration forage produced from their own trees/shrubs, or from other local sources.