• Address:
  705 Spear Street
  South Burlington, Vermont 05403
  United States of America
  
  Phone: (802) 391-4135
  Email: femc@uvm.edu
  Website: www.uvm.edu/femc

Measure foliar nitrogen of sugar maple to determine relationships between leaf nitrogen content and resorption efficiency during autumn leaf senescence. To examine the variability in resorption efficiency among and within sugar maple trees. To establish a baseline for long-term nutrient cycling research. To examine the variability in resorption efficiency and foliar N content among and within sugar maple trees. To determine the relationship between resorption efficiency and foliar N content.

• Label: ID

• Description: Site Id

• Storage Type: text

• Measurment Type: nominal

• Label: Tree Number

• Description: Number assigned to identify tree

• Storage Type: int

• Measurment Type: nominal
• Standard Unit: dimensionless
• Precision: 1
• Number Type: integer

• Label: Sample Date

• Description: Date sample was collected

• Storage Type: datetime

• Measurment Type: datetime
• String Format: YYYY-MM-DD

• Label: Tree Sample Location

• Description: Location of sample collection in tree

• Storage Type: text

• Measurment Type: nominal

• Custom List: Location Code
• Code: LN
• Definition: lower canopy on north side of tree
• Code: LS
• Definition: lower canopy on south side of tree
• Code: MN
• Definition: middle canopy north side of tree
• Code: MS
• Definition: middle canopy south side of tree
• Code: UN
• Definition: upper canopy north side of tree
• Code: US
• Definition: uppers canopy south side of tree

• Label: Area

• Description: Area of leaf surface

• Storage Type: decimal

• Measurment Type: ratio
• Standard Unit: squareCentimeters
• Precision: 0.01
• Unit: squareCentimeters
• Number Type: real

• Label: Thrips Damage Index

• Description: All green leaf samples were assigned a pear thrips damage index number

• Storage Type: int

• Measurment Type: ordinal
• Standard Unit: dimensionless
• Precision: 1
• Number Type: integer

• Label: Dry Weight

• Description: Weight of leaves or lead litter oven dried at 70 degrees Celsius

• Storage Type: decimal

• Measurment Type: ratio
• Standard Unit: gram
• Precision: 0.01
• Unit: gram
• Number Type: real

• Label: CHN weight

• Description: Weight determined by CHN elemental analyzer (weight of leaf of leaf litter sample)

• Storage Type: int

• Measurment Type: ratio
• Standard Unit: microgram
• Precision: 10
• Unit: microgram
• Number Type: real

• Label: Percent Nitrogen

• Description: Percent nitrogen

• Storage Type: decimal

• Measurment Type: ratio
• Standard Unit: percent
• Precision: 0.01
• Unit: percent
• Number Type: real

• Label: QC Adjust

• Description: QC adjustment

• Storage Type: text

• Measurment Type: nominal

• Label: ug N/cm^2

• Description: Micrograms of nitrogen per centimeter squared: the amount of nitrogen found in a given area

• Storage Type: decimal

• Measurment Type: ratio
• Standard Unit: squareCentimeters
• Precision: 0.000000001
• Unit: squareCentimeters
• Number Type: real

• Label: Average ug N/cm^2

• Description: Mean micrograms of nitrogen per centimeter squared for all sample sites in a tree

• Storage Type: decimal

• Measurment Type: ratio
• Standard Unit: squareCentimeters
• Precision: 0.001
• Unit: squareCentimeters
• Number Type: real

• Label: mg N/g

• Description: Milligrams nitrogen per gram

• Storage Type: decimal

• Measurment Type: ratio
• Standard Unit: nanogram
• Precision: 0.0001
• Unit: nanogram
• Number Type: real

• Study specimens
  • Started: 1993-05-01
    
  • Method Description: Twenty sugar maple trees used for foliage sampling.

• Plot description
  • Method Description: One 75 X 50 m plot used for soil, litter, throughfall and precipitation collections.

• Leaf samples
  • Method Description: Leaf samples collected from north and south sides of tree; from lower, middle and upper canopy. Samples of leaves were collected once in mid-July and once in mid-August to obtain a measure of the maximum nitrogen pool. Foliar nutrient concentrations are most stable in this time frame.

• Leaf litter
  • Started: 1993-09-20
    
  • Method Description: Leaf litter traps collected twice weekly. One litter trap was placed under each tree, positioned so that minimal litter would fall in from surrounding trees. Leaf litter was collected throughout the leaf drop period (September 20-October 22).

• Throughfall collection
  • Method Description: Throughfall collections consisted of two funnel collectors under each of five trees, on north and south sides of tree. Plus two collectors in an open area in close proximity to the site to collect rain as a control.

• Leaf tissue analysis
  • Method Description: After each sampling, leaf tissue was run through a leaf area meter, assigned a thrips damage index number, oven dried at 70 degrees C to a constant weight and ground in a Wiley mill.

• Chromatograph
• Sampling Description: Dionex Ion Chromatograph Model 2010i was used to analyze nitrate.

• Flow injection analysis
• Sampling Description: Lachat Quick Chem AE flow injection analysis was used to test ammonium colorimetrically.

• Elemental Analyzer
• Started: 1993-05-01
  
• Sampling Description: Leeman Laboratories CHN CE440 Elemental Analyzer was used to determine total nitrogen.

• Leaf litter traps, funnel precipitation colle
• Started: 1993-05-01
  
• Sampling Description: Leaf litter traps. Funnel precipitation collectors.

• Pole pruners, ladders and rope climbing equip
• Started: 1993-05-01
  
• Sampling Description: Pole pruners, ladders and rope climbing equipment.