Harvard Forest Data Archive

HF361

Nonstructural Carbon, Phenology and Wood Formation in Three Tree Species at Harvard Forest 2017-2019

Related Publications

Data

• hf361-01: allometric data (preview)
• hf361-02: growth data from band width measurements (preview)
• hf361-03: growth data from cell counts (preview)
• hf361-04: list of samples for nonstructural carbon data (preview)
• hf361-05: nonstructrual carbon data for foliage samples (preview)
• hf361-06: nonstructrual carbon data for first cm of increment core samples (preview)
• hf361-07: data for the calibration curves and laboratory control standards for the wood samples (preview)
• hf361-08: stem CO2 efflux data (preview)
• hf361-09: leaf phenology, spring and fall (preview)

Overview

• Lead: Tim Rademacher
• Investigators: Andrew Richardson, Mark VanScoy
• Contact: Information Manager
• Start date: 2017
• End date: 2019
• Status: complete
• Location: Prospect Hill Tract (Harvard Forest)
• Latitude: +42.51 degrees
• Longitude: -72.22 degrees
• Elevation: 340 meter
• Datum: WGS84
• Taxa: Acer rubrum, Quercus rubra, Pinus strobus
• Release date: 2023
• Language: English
• EML file: knb-lter-hfr.361.3
• DOI: digital object identifier
• EDI: data package
• DataONE: data package
• Related links:
• Phenology of Woody Species at Harvard Forest since 1990
• Density Anomalies in White Pine at Harvard Forest 2019
• White Pine Girdling and Compression Experiment at Harvard Forest 2017-2019
• Investigating Wood Growth, Wood Properties and Carbon Metabolism in Young White Pines in Tom Swamp
• WIAD: Wood Image Analysis and Dataset
• Study type: short-term measurement
• Research topic: forest-atmosphere exchange; international research projects; physiological ecology, population dynamics and species interactions
• LTER core area: primary production
• Keywords: aboveground biomass, carbohydrates, carbon, maple, oak, phenology, pine, tree growth, tree rings
• Abstract:

  This data set comprises various observations and measurements across the 2017 to 2019 growing season for seven red maple (Acer rubrum), eight red oak (Quercus rubra), and six white pine (Pinus strobus) in the Prospect Hill Tract of Harvard Forest. The observations include spring and fall leaf phenology and basic allometry, such as diameter at breast height and height. For the leaf phenology, we followed the protocol from John O’Keefe (HF003). Measurements include wood growth data from weekly microcores and a three time characterisation of growing season nonstructural carbon concentrations (soluble sugars and starch) for stems and leaves. Additionally, stem CO2 efflux was measured once a month for the 2018 growing season and weekly for the 2019 growing season.

• Methods:

  Allometric data

  Diameters were measured with a diameter tape at 1.5 m above the root collar at the beginning of the study in February 2017. Heights were measured three times with a laser hypsometer in February of 2017. Ages were estimated by simply counting growth rings from two increment cores taken in 2020 with a standard increment corer and prepared according to dendrochronological procedures (mounting, sanding, etc.).

  Wood growth

  Microcores were collected on a weekly basis using a Trephor tool (Rossi et al., 2006). The cores were stored in solution (75% ethanol (95%) and 25% glacial acetic acid) for 24 hours, when they were transferred to only ethanol (95%) until further processing. Microsections were double-stained with astra-blue and safranin after cutting (7 μm-thick cross-sectional cuts) with a rotary microtome (Leica RM2245, Switzerland) from paraffin-embedded samples (Tissue Processor 1020 Leica, Switzerland). Images of the microsections were captured using a digital slide-scanner (Zeiss Axio Scan.Z1, Germany) with a resolution of roughly 1.5 pixels per μm. Cell counts for each developmental process (cambial, enlargening, thickening, and mature cells) were performed on three radial files and their band widths were measured using the Wood Image Analysis and Database (https://wiad.science; Rademacher et al., 2021).

  Nonstructural carbon

  Stem and foliage soluble sugar and starch concentrations were determined from tissue samples collected at the first Wednesday of each month throughout the growing season. Stems were cored using an increment borer (5.15 mm diameter, Haglӧf Company Group, Långsele, Sweden). Foliage samples were collected from a sun-exposed part of the crown with a bucket lift and pole pruner. All sampled tissues were immediately shock-frozen on dry ice in the field and kept frozen until further processing (-60℃). Samples were eventually cut using razor blades and freeze-dried (FreeZone 2.5, Labconco, Kansas City, Missouri, USA and Hybrid Vacuum Pump, Vaccubrand, Wertheim, Germany). Dried samples were ground by Wiley mill with mesh 20 (Thomas Scientific Wiley Mill, Swedesboro, New Jersey, USA) and homogenised (SPEX SamplePrep 1600, MiniG, Metuchen, New Jersey, USA). For white pine, we processed an equal mix of first- and second-year needles, while we used several leaves for maples and oak. For stems, we homogenised the first centimetre of xylem tissue without the bark and phloem. For all samples about 40 mg of finely ground and dried powder was analysed using a colourimetric assay with phenol-sulfuric acid following ethanol extraction according to the protocol by Chow and Landhäusser (2004) as adapted by Furze et al. (2019). Using a spectrophotometer (Thermo Fisher Scientific GENESYS 10S UV-Vis, Waltham, Massachusetts, USA) we read absorbances twice at 490 nm for sugar and 525 nm for starch, and calibrated the absorbance values with a 1:1:1 glucose:fructose:galactose (Sigma Chemicals, St. Louis, Missouri, USA) standard curve for sugar and a glucose (Sigma Chemicals, St. Louis, Missouri, USA) standard curve for starch. Each batch of samples included roughly 40 samples, including always both tube and sample blanks and additional laboratory control standards for quality control (red oak stem wood, Harvard Forest, Petersham, Massachusetts, USA; potato starch, Sigma Chemicals, St. Louis, Missouri, USA). All samples’ absorbance values were converted to concentrations in % dry weight and uncertainties with the self-developed R package NSCprocessR (https://github.com/TTRademacher/NSCprocessR).

  Stem CO2 efflux

  Stem CO2 efflux was measured using the Flux Puppy system (Carbone et al., 2019). Chambers (10 cm diameter by 10 cm length PVC pipe) were cut to fit each tree’s stem curvature at 1.5 m and attached to all trees in April of 2018 silicone adhesive. An infrared gas analyser (LI-820 or LI-840, LI-COR, Lincoln, Nebraska, USA) with a circulating pump (12K, Boxer, Ottobeuren, Germany) was attached to the chambers using a PVC cap with two ports to constantly circulate air through the closed system. Once the lid was closed and the concentration stabilised, the chamber CO2 concentration was measured at 1 Hz for at least 90 seconds. To minimise any effect of diel and environmental influences on treatment differences in CO2 efflux, we measured CO2 efflux at the same time of day for each tree throughout the measurement campaign starting around 13:00h local time. The raw stem CO2 efflux and uncertainties were estimated using the RespChamberProc package (https://r-forge.r-project.org/projects/respchamberproc; Perez-Priego et al., 2015).

  Leaf phenology

  Leaf phenology was observed following the protocol by John O’Keefe (HF003) for all trees in our study.

  Publications cited

  Chow and Landhäusser (2004) “A method for routine measurements of total sugar and starch content in woody plant tissues”, Tree Physiology, 24 (10), 1120-1136, doi:10.1093/treephys/24.10.1129

  Perez-Priego et al. (2015) “Sun-induced chlorophyll fluorescence and photochemical reflectance index improve remote-sensing gross primary production estimates under varying nutrient availability in a typical Mediterranean savanna ecosystem”, Biogeosciences, 12 (21), 6351-6367, doi:10.5194/bg-12-6351-2015

  Rademacher et al. (2021) “The Wood Image Analysis and Dataset (WIAD): open-access visual analysis tools to advance the ecological data revolution”, Methods in Ecology and Evolution 12: 2379-2387. doi:https://doi.org/10.1101/2020.12.16.423133

  Rossi et al. (2006) “Trephor: A New Tool for Sampling Microcores from tree stems”, IAWA Journal, 89-97, doi:10.1163/22941932-90000139

• Organization: Harvard Forest. 324 North Main Street, Petersham, MA 01366, USA. Phone (978) 724-3302. Fax (978) 724-3595.

• Project: The Harvard Forest Long-Term Ecological Research (LTER) program examines ecological dynamics in the New England region resulting from natural disturbances, environmental change, and human impacts. (ROR).

• Funding: National Science Foundation LTER grants: DEB-8811764, DEB-9411975, DEB-0080592, DEB-0620443, DEB-1237491, DEB-1832210.

• Use: This dataset is released to the public under Creative Commons CC0 1.0 (No Rights Reserved). Please keep the dataset creators informed of any plans to use the dataset. Consultation with the original investigators is strongly encouraged. Publications and data products that make use of the dataset should include proper acknowledgement.

• License: Creative Commons Zero v1.0 Universal (CC0-1.0)

• Citation: Rademacher T. 2023. Nonstructural Carbon, Phenology and Wood Formation in Three Tree Species at Harvard Forest 2017-2019. Harvard Forest Data Archive: HF361 (v.3). Environmental Data Initiative: https://doi.org/10.6073/pasta/338e836be7cd3a5b7d4b7aabe54a2969.

Detailed Metadata

hf361-01: allometric data

1. tree.id: tree identifier
2. species: tree species
   • Acer rubrum: red maple
   • Pinus strobus: white pine
   • Quercus rubrum: red oak
3. utm18T.easting: location of tree stem base with reference to UTM 18T (unit: meter / missing value: NA)
4. utm18T.northing: location of tree stem base with reference to UTM 18T (unit: meter / missing value: NA)
5. circumference: tree stem circumference at 1.5 m (unit: centimeter / missing value: NA)
6. radius: tree stem radius at 1.5 m (unit: centimeter / missing value: NA)
7. diameter: tree stem diameter at 1.5 m (unit: centimeter / missing value: NA)
8. h1: first tree height measurement (unit: meter / missing value: NA)
9. h2: second tree height measurement (unit: meter / missing value: NA)
10. h3: third tree height measurement (unit: meter / missing value: NA)
11. h: mean tree height (unit: meter / missing value: NA)
12. age: minimum estimate of tree age in years from counting visible growth rings in increment cores (unit: number / missing value: NA)
13. comments: comments

hf361-02: growth data from band width measurements

1. study: type of study
   • Obs: observational study without treatment
2. tree.id: identifier for the tree
3. species: tree species
   • Acer rubrum: red maple
   • Pinus strobus: white pine
   • Quercus rubra: red oak
4. sample.number: number of the sample collected for that particular species in that specific year
5. year: year during which the sample was collected
6. date: date on which the sample was collected
7. doy: day of the year on which the sample was collected (unit: nominalDay / missing value: NA)
8. c1: band width of cambial cell in first radial file (unit: micrometer / missing value: NA)
9. c2: band width of cambial cell in second radial file (unit: micrometer / missing value: NA)
10. c3: band width of cambial cell in third radial file (unit: micrometer / missing value: NA)
11. cq: quality of cambial cell observations
    • 0: very poor quality — counting or measurements are not done directly on the section, but are guessed by the expert using all the clues available on the section
    • 1: poor quality — counting or measurements are based on only one complete radial file
    • 2: decent quality — counting or measurements are based on few adjacent complete radial files
    • 3: good quality — counting or measurements are based on few complete radial files distributed in different regions of the section, but shapes or colours are blurred
    • 4: very good quality — counting or measurements are based on several complete radial files distributed in different regions of the section, shapes and colours are plain
    • 5: excellent quality — perfect anatomical section (to keep for illustrations)
12. e1: band width of expanding cells in the first radial file (unit: micrometer / missing value: NA)
13. e2: band width of expanding cells in the second radial file (unit: micrometer / missing value: NA)
14. e3: band width of expanding cells in the third radial file (unit: micrometer / missing value: NA)
15. eq: quality of expanding cell observations with the same key as column 10 “cq”
16. w1: band width of thickening cells in the first radial file (unit: micrometer / missing value: NA)
17. w2: band width of thickening cells in the second radial file (unit: micrometer / missing value: NA)
18. w3: band width of thickening cells in the third radial file (unit: micrometer / missing value: NA)
19. wq: quality of thickening cell observations with the same key as column 10 “cq”
20. m1: band width of cells in the first radial file (unit: micrometer / missing value: NA)
21. m2: band width of cells in the second radial file (unit: micrometer / missing value: NA)
22. m3: band width of mature cells in the third radial file (unit: micrometer / missing value: NA)
23. mq: quality of mature cell observations with the same key as column 10 “cq”
24. p1: tree-ring width in the first radial file of the previous tree-ring, aka year before the monitoring (unit: micrometer / missing value: NA)
25. p2: tree-ring width in the second radial file of the previous tree-ring, aka year before the monitoring (unit: micrometer / missing value: NA)
26. p3: tree-ring width in the third radial file of the previous tree-ring, aka year before the monitoring (unit: micrometer / missing value: NA)
27. pq: quality of width measurements of previous tree-ring with the same key as column 10 “cq”
28. comments: comments

hf361-03: growth data from cell counts

1. study: type of study
   • Obs: observational study without treatment
2. tree.id: identifier for the tree
3. species: tree species
   • Acer rubrum: red maple
   • Pinus strobus: white pine
   • Quercus rubrum: red oak
4. sample.number: number of the sample collected for that particular species in that specific year
5. year: year during which the sample was collected
6. date: date on which the sample was collected
7. doy: day of the year on which the sample was collected (unit: nominalDay / missing value: NA)
8. c1: number of cambial cells in first radial file (unit: number / missing value: NA)
9. c2: number of cambial cells in second radial file (unit: number / missing value: NA)
10. c3: number of cambial cells in third radial file (unit: number / missing value: NA)
11. cq: quality of cambial cell observations
    • 0: very poor quality — counting or measurements are not done directly on the section, but are guessed by the expert using all the clues available on the section
    • 1: poor quality — counting or measurements are based on only one complete radial file
    • 2: decent quality — counting or measurements are based on few adjacent complete radial files
    • 3: good quality — counting or measurements are based on few complete radial files distributed in different regions of the section, but shapes or colours are blurred
    • 4: very good quality — counting or measurements are based on several complete radial files distributed in different regions of the section, shapes and colours are plain
    • 5: excellent quality — perfect anatomical section (to keep for illustrations)
12. e1: number of expanding cells in the first radial file (unit: number / missing value: NA)
13. e2: number of expanding cells in the second radial file (unit: number / missing value: NA)
14. e3: number of expanding cells in the third radial file (unit: number / missing value: NA)
15. eq: quality of expanding cell observations with the same key as column 10 “cq”
16. w1: number of thickening cells in the first radial file (unit: number / missing value: NA)
17. w2: number of thickening cells in the second radial file (unit: number / missing value: NA)
18. w3: number of thickening cells in the third radial file (unit: number / missing value: NA)
19. wq: quality of thickening cell observations with the same key as column 10 “cq”
20. m1: number of mature cells in the first radial file (unit: number / missing value: NA)
21. m2: number of mature cells in the second radial file (unit: number / missing value: NA)
22. m3: number of mature cells in the third radial file (unit: number / missing value: NA)
23. mq: quality of mature cell observations with the same key as column 10 “cq”
24. p1: tree-ring width in the first radial file of the previous tree-ring, aka year before the monitoring (unit: micrometer / missing value: NA)
25. p2: tree-ring width in the second radial file of the previous tree-ring, aka year before the monitoring (unit: micrometer / missing value: NA)
26. p3: tree-ring width in the third radial file of the previous tree-ring, aka year before the monitoring (unit: micrometer / missing value: NA)
27. pq: quality of width measurements of previous tree-ring with the same key as column 10 “cq”
28. comments: comments

hf361-04: list of samples for nonstructural carbon data

1. study: type of study
   • Obs: observational study without treatment
2. tree.id: identifier for the tree
3. tissue: type of tissue of the sample
4. date: date of sample collection
5. rc.lab.number: lab-internal number identifying the sample in the Richardson-Carbone lab at Northern Arizona University
6. month: month of sample collection (unit: number / missing value: NA)
7. day: day of sample collection (unit: number / missing value: NA)
8. year: year of sample collection
9. month.abbreviation: month of sample collection

hf361-05: nonstructrual carbon data for foliage samples

1. rc.lab.number: lab-internal number identifying the sample in the Richardson-Carbone lab at Northern Arizona University
2. sample.id: identifier for the sample
3. tissue: type of tissue of the sample
   • B: blank
   • Foliage: foliage tissue
   • LCS: laboratory control standard
   • Ref: reference values of various concentrations
   • Root: root
   • Stem: stem tissue
   • TB: tube blank
   • Wood: wood
4. batch.id: identifier of the batch of samples, as all samples were generally processed in batches of 40 tubes (including laboratory standards, reference values for calibration, tube blanks, and sample blanks)
5. sample.location: sample site
6. date: date of sample collection
7. date.sugar.analysis: date the sugar analysis of the sample was performed
8. date.starch.analysis: date the starch analysis of the sample was performed
9. mass.empty: mass of the empty tube without the sample (unit: gram / missing value: NA)
10. mass: mass of the tube with the sample (unit: gram / missing value: NA)
11. absorbance490.1: first absorbance value reading at 490 nm (unit: dimensionless / missing value: NA)
12. absorbance490.2: second absorbance value reading at 490 nm (unit: dimensionless / missing value: NA)
13. absorbance490.blank: absorbance value reading at 490 nm for the blank (unit: dimensionless / missing value: NA)
14. absorbance525.1: first absorbance value reading at 525 nm (unit: dimensionless / missing value: NA)
15. absorbance525.2: second absorbance value reading at 525 nm (unit: dimensionless / missing value: NA)
16. dilution.factor.sugar: factor by which the sugar extract was diluted (unit: dimensionless / missing value: NA)
17. volume.sugar: volume of the sugar extract (unit: milliliter / missing value: NA)
18. dilution.factor.starch: factor by which the starch extract was diluted (unit: dimensionless / missing value: NA)
19. volume.starch: volume of the starch extract (unit: milliliter / missing value: NA)
20. comments: comments

hf361-06: nonstructrual carbon data for first cm of increment core samples

1. rc.lab.number: lab-internal number identifying the sample in the Richardson-Carbone lab at Northern Arizona University
2. sample.id: identifier for the sample
3. tissue: type of tissue of the sample
   • B: blank
   • Foliage: foliage tissue
   • LCS: laboratory control standard
   • Ref: reference values of various concentrations
   • Root: root
   • Stem: stem tissue
   • TB: tube blank
   • Wood: wood
4. batch.id: identifier of the batch of samples, as all samples were generally processed in batches of 40 tubes (including laboratory standards, reference values for calibration, tube blanks, and sample blanks)
5. sample.location: sample site
6. date: date of sample collection
7. date.sugar.analysis: date the sugar analysis of the sample was performed
8. date.starch.analysis: date the starch analysis of the sample was performed
9. mass.empty: mass of the empty tube without the sample (unit: gram / missing value: NA)
10. mass: mass of the tube with the sample (unit: gram / missing value: NA)
11. absorbance490.1: first absorbance value reading at 490 nm (unit: dimensionless / missing value: NA)
12. absorbance490.2: second absorbance value reading at 490 nm (unit: dimensionless / missing value: NA)
13. absorbance490.blank: absorbance value reading at 490 nm for the blank (unit: dimensionless / missing value: NA)
14. absorbance525.1: first absorbance value reading at 525 nm (unit: dimensionless / missing value: NA)
15. absorbance525.2: second absorbance value reading at 525 nm (unit: dimensionless / missing value: NA)
16. dilution.factor.sugar: factor by which the sugar extract was diluted (unit: dimensionless / missing value: NA)
17. volume.sugar: volume of the sugar extract (unit: milliliter / missing value: NA)
18. dilution.factor.starch: factor by which the starch extract was diluted (unit: dimensionless / missing value: NA)
19. volume.starch: volume of the starch extract (unit: milliliter / missing value: NA)
20. comments: comments

hf361-07: data for the calibration curves and laboratory control standards for the wood samples

1. rc.lab.number: lab-internal number identifying the sample in the Richardson-Carbone lab at Northern Arizona University
2. sample.id: identifier for the sample
3. tissue: type of tissue of the sample
   • B: blank
   • Foliage: foliage tissue
   • LCS: laboratory control standard
   • Ref: reference values of various concentrations
   • Root: root
   • Stem: stem tissue
   • TB: tube blank
   • Wood: wood
4. batch.id: identifier of the batch of samples, as all samples were generally processed in batches of 40 tubes (including laboratory standards, reference values for calibration, tube blanks, and sample blanks)
5. sample.location: sample site
6. date: date of sample collection
7. date.sugar.analysis: date the sugar analysis of the sample was performed
8. date.starch.analysis: date the starch analysis of the sample was performed
9. mass.empty: mass of the empty tube without the sample (unit: gram / missing value: NA)
10. mass: mass of the tube with the sample (unit: gram / missing value: NA)
11. absorbance490.1: first absorbance value reading at 490 nm (unit: dimensionless / missing value: NA)
12. absorbance490.2: second absorbance value reading at 490 nm (unit: dimensionless / missing value: NA)
13. absorbance490.blank: absorbance value reading at 490 nm for the blank (unit: dimensionless / missing value: NA)
14. absorbance525.1: first absorbance value reading at 525 nm (unit: dimensionless / missing value: NA)
15. absorbance525.2: second absorbance value reading at 525 nm (unit: dimensionless / missing value: NA)
16. dilution.factor.sugar: factor by which the sugar extract was diluted (unit: dimensionless / missing value: NA)
17. volume.sugar: volume of the sugar extract (unit: milliliter / missing value: NA)
18. dilution.factor.starch: factor by which the starch extract was diluted (unit: dimensionless / missing value: NA)
19. volume.starch: volume of the starch extract (unit: milliliter / missing value: NA)
20. comments: comments

hf361-08: stem CO2 efflux data

1. file: name of the raw data file
2. study: study
   • Obs: obervational study without treatment
3. treatment: possible experimental treatment
   • 1: control
4. tree.id: identifier for tree
5. species: tree species
   • Acer rubrum: red maple
   • Pinus strobus: white pine
   • Quercus rubra: red oak
6. chamber: chamber identifier
   • 1: 1.5 m above ground on main stem
7. chamber.volume: volume of the respiration chamber (unit: cubicMeter / missing value: NA)
8. chamber.area: stem surface area covered by the chamber (unit: squareMeter / missing value: NA)
9. datetime: time stamp of when the measurement was started
10. session: identifier for the session of respiration measurements, which was needed for processing
11. flux.raw: mean CO2 efflux from given chamber (unit: micromolePerMeterSquaredPerSecond / missing value: NA)
12. sd.flux.raw: standard deviation of respiratory flux from given chamber (unit: micromolePerMeterSquaredPerSecond / missing value: NA)
13. aic.raw: Akaike Information Criterion of linear regression model fitted to CO2 curve (unit: dimensionless / missing value: NA)
14. r2.raw: R2 of the fitted linear regression model fitted to CO2 curve (unit: dimensionless / missing value: NA)
15. flux.atm: mean CO2 efflux from given chamber after correction for water vapor dilution using atmospheric humidity (unit: micromolePerMeterSquaredPerSecond / missing value: NA)
16. sd.flux.atm: standard deviation of respiratory flux from given chamber after correction for water vapor dilution using atmospheric humidity (unit: micromolePerMeterSquaredPerSecond / missing value: NA)
17. aic.atm: Akaike Information Criterion of linear regression model fitted to CO2 curve after correction for water vapor dilution using atmospheric humidity (unit: dimensionless / missing value: NA)
18. r2.atm: R2 of the fitted linear regression model fitted to CO2 curve after correction for water vapor dilution using atmospheric humidity (unit: dimensionless / missing value: NA)
19. flux.int: mean CO2 efflux from given chamber after correction for water vapor dilution using internal humidity from LiCOR-840 (unit: micromolePerMeterSquaredPerSecond / missing value: NA)
20. sd.flux.int: standard deviation of respiratory flux from given chamber after correction for water vapor dilution using internal humidity from LiCOR-840 (unit: micromolePerMeterSquaredPerSecond / missing value: NA)
21. aic.int: Akaike Information Criterion of linear regression model fitted to CO2 curve after correction for water vapor dilution using internal humidity from LiCOR-840 (unit: dimensionless / missing value: NA)
22. r2.int: R2 of the fitted linear regression model fitted to CO2 curve after correction for water vapor dilution using internal humidity from LiCOR-840 (unit: dimensionless / missing value: NA)
23. ea.pa: atmospheric water vapor pressure calculated from humidity from Fisher meteorological station at time of measurement (unit: pascal / missing value: NA)
24. airt.c: surface air temperature at time of measurement (unit: celsius / missing value: NA)
25. soilt1.c: soil temperature at 2.25 cm near the Barn Tower at time of measurement (unit: celsius / missing value: NA)
26. soilt2.c: soil temperature at 6.80 cm near the Barn Tower at time of measurement (unit: celsius / missing value: NA)
27. soilt3.c: soil temperature at 12.85 cm near the Barn Tower at time of measurement (unit: celsius / missing value: NA)
28. soilt4.c: soil temperature at 22.75 cm near the Barn Tower at time of measurement (unit: celsius / missing value: NA)
29. pres.pa: atmospheric barometric pressure from Fisher meteorological station at time of measurement (unit: celsius / missing value: NA)
30. h2o.ppt.atm: atmospheric humidity from Fisher meteorological station at time of measurement in parts per thousand (unit: dimensionless / missing value: NA)
31. h2o.ppt.int: internal humidity from LiCOR-840 at time of measurement in parts per thousand (unit: dimensionless / missing value: NA)
32. vwc.daily: daily mean volumetric water content from probes near the Barn Tower for day of measurement (unit: dimensionless / missing value: NA)
33. vwc1: 10-mean volumetric water content at 2.25 cm from probe near the Barn Tower at time of measurement (unit: dimensionless / missing value: NA)
34. vwc2: 10-mean volumetric water content at 6.80 cm from probe near the Barn Tower at time of measurement (unit: dimensionless / missing value: NA)
35. vwc3: 10-mean volumetric water content at 12.85 cm from probe near the Barn Tower at time of measurement (unit: dimensionless / missing value: NA)
36. vwc4: 10-mean volumetric water content at 22.75 cm from probe near the Barn Tower at time of measurement (unit: dimensionless / missing value: NA)
37. total.rad: total downwelling shortwave radiation at the top of the Barn Tower at time of measurement (unit: wattPerMeterSquared / missing value: NA)
38. diffuse.rad: diffuse downwelling shortwave radiation at the top of the Barn Tower at time of measurement (unit: wattPerMeterSquared / missing value: NA)

hf361-09: leaf phenology, spring and fall

1. study: study
   • Obs: observational study without treatment
2. treatment: possible experimental treatment
   • 1: control
3. year: year of measurement
4. tree.id: tree identifier
5. species: tree species
   • Acer rubrum: red maple
   • Pinus strobus: white pine
   • Quercus rubrum: red oak
6. bb.doy: day of year on which 50% of the buds were open with visible leaves (unit: nominalDay / missing value: NA)
7. l75.doy: day of year on which 50% of the leaves were developed to 75% of their final size (unit: nominalDay / missing value: NA)
8. fbb.doy: day of year on which flower buds first broke with petals visible (unit: nominalDay / missing value: NA)
9. fopn.doy: day of year on which 50% of the flower buds were open (unit: nominalDay / missing value: NA)
10. lc.doy: day of year on which 50% of the leaves have changed color on a given tree (unit: nominalDay / missing value: NA)
11. lf.doy: day of year on which 50% of the leaves have fallen from a given tree (unit: nominalDay / missing value: NA)
12. comments: comments