PRINCIPAL INVESTIGATOR
      Wayne C. Martin
      USDA Forest Service
      Hubbard Brook Experimental Forest
      West Thornton, NH
      Telephone: (603) 726-8902

BEGIN DATE
      1989

END DATE
      1992

LOCATION
      WS 1,4,5,6,7

DATA DESCRIPTION
       Routine observations of phenology at HBEF were begun in the spring of 1989. The objective of the observations is to provide repeatable, quantified phenology data in a way that takes little time. Observations are made once a week during the spring and fall.

SAMPLING DESIGN
       Each location as described above (1B, 6T, etc) is a specific point along the weekly watershed rounds route which is permanently marked. Visible from each location are three dominant or codominant trees of each of the three species: sugar maple, yellow birch, and beech. These individual trees are permanently marked on the side toward the "location" mark. When possible, their crowns are visible from the location itself to minimize the amount of moving around that is necessary. For each tree at each location, and each week, one number is recorded in spring, and one in autumn. Observations are not needed in winter or in summer unless insect attack causes premature senescence or leaffall.

ACCESS
      Public

DATA LOCATION
      USDA Forest Service, Durham, NH

LAST UPDATED
      1992

CONTACT PERSON
      John Campbell
      PO Box 640
      Durham, NH 03824
      Telephone: (603) 868-7643
      E-mail: johnc@global.unh.edu

VARIABLES

Column	Variable	Description	Units	Coded	Missing Value
1	Date	Sample date	yymmdd	n	none
2	Day	Sample day	ddd	n	none
Sugar maple
3	1B	Tree at bottom of WS1		y	not within range
4	6T	Tree at top of WS6		y	not within range
5	4B	Tree at bottom of WS4, oldest strips		y	not within range
6	4T	Tree at top of WS4, oldest strips		y	not within range
7	5B	Tree at bottom of WS5		y	not within range
8	5T	Tree at top of WS5		y	not within range
9	7B	Tree at bottom of WS7 (or 8)		y	not within range
10	7T	Tree at top of WS7 (or 8)		y	not within range
American beech
11	1B	Tree at bottom of WS1		y	not within range
12	6T	Tree at top of WS6		y	not within range
13	4B	Tree at bottom of WS4, oldest strips		y	not within range
14	4T	Tree at top of WS4, oldest strips		y	not within range
15	5B	Tree at bottom of WS5		y	not within range
16	5T	Tree at top of WS5		y	not within range
17	7B	Tree at bottom of WS7 (or 8)		y	not within range
18	7T	Tree at top of WS7 (or 8)		y	not within range
Yellow birch
19	1B	Tree at bottom of WS1		y	not within range
20	6T	Tree at top of WS6		y	not within range
21	4B	Tree at bottom of WS4, oldest strips		y	not within range
22	4T	Tree at top of WS4, oldest strips		y	not within range
23	5B	Tree at bottom of WS5		y	not within range
24	5T	Tree at top of WS5		y	not within range
25	7B	Tree at bottom of WS7 (or 8)		y	not within range
26	7T	Tree at top of WS7 (or 8)		y	not within range

CODES

SPRING CRITERIA
0	no change from winter conditions unexpanded buds only
1	bud swelling noticeable
2	small leaves or flowers visible initial stages of leaf expansion leaves about 1 cm long
3	leaves 1/2 of final length leaves 5 cm long leaves obscure 1/2 of sky as seen through crowns
3.5	leaves 3/4 expanded sky mostly obscured through crown crowns not yet in summer condition
4	canopy appears in summer condition leaves fully expanded little sky visible through crowns
AUTUMN CRITERIA
4	canopy appears in summer condition only scattered leaves or branches have any color change
3	many leaves have noticeable reddening or yellowing much green still present
2	most leaves yellow or red few leaves have fallen leaves still obscure most of sky as seen through crowns
1	no more green in canopy half of leaves have fallen leaves still obscure half of sky as seen through crown
0.5	most leaves fallen
0	all leaves fallen except remnants on beech winter condition

*DECIMAL INTERPOLATION BETWEEN VALUES IS ALLOWED, E.G. 2.2, 3.5

NOTES
Eight locations have been established for observations (described above). After three years these may be reduced in number if timing of events differs consistently among locations.

DATA FILE NAME(S)
       phen.txt