1937 Vegetation Inventory (3000 acres)

• Investigators: N Hosley
• Contact: David Foster
• Start date: 1937-01-01
• End date: 1937-12-31
• Location: Harvard Forest
• Latitude: +42.45 to +42.55
• Longitude: -72.23 to -72.16
• Elevation: 205 to 420 meters
• Taxa:
• Keywords: forest dynamics, inventory
• Release date: 2003
• EML version: knb-lter-hfr.39.2
• Revisions:
• Abstract:

  The three main tracts of the Harvard Forest (3000 acres) in Petersham, MA have been sampled every 10-30 years since 1907. Though methods have varied, each survey has involved mapping forest stands followed by intensive sampling. The 1937 forest inventory was conducted one year before 75% of the standing timber at Harvard Forest was blown down by the 1938 hurricane. This valuable data set shows maximum vegetation development since agricultural abandonment. Data collected in this inventory include tree volume by species and presence/absence of advance regeneration, shrubs, herbs and bryophytes.

• Methods:

  Introduction

  The following "Directions for Reinventory of Forest, 1937" were transcribed by Audrey Barker Plotkin from original in HF Archives.

  Boundary Survey

  Compartment Boundaries: All are to be surveyed by transit and tape within accuracy limits of 2:1000. Notes are to be computed by latitudes and departures. Main corners of external boundaries are to be marked with 1" galvanized pipes having brass caps marked with H. F. and a set of serial numbers for each block, the numbers starting with one at the westernmost part and going clockwise around the block. Internal compartment lines and minor corners of external boundaries are to be marked by iron pipes. All pipes (but not the caps) are to be painted orange.

  Course

  Mapping: Any stands of 1/40 acre or over are to be mapped.

  Method of Cruising: A modification of the line-plot method with circular plots of ¼ acre (59' radius), or halves or quarters of this is to be used. In stands large enough to warrant it plots are to be spaced evenly at either 600' (27% cruise) or 800' (15%) intervals on the cruise lines according to the uniformity of the stand. Lines will be run N. - S. or E. - W. so as to accurately locate the boundaries of all stands. In most of the Forest this will necessitate distances between lines of not more than 300'. In compartments not broken up by big cuttings or openings, lines will be run from boundary to boundary but this does not necessarily have to be followed where offsets will more effectively tie in the stands. In small stands plots will be located either on or off the lines according to judgment as to where the most representative samples can be gotten.

  Plot Description

  A number will be assigned to each plot taken by means of a metal tag nailed to the central tree on the south side at or near d.b.h. This number will be placed on the field map with a circle to show the plot location.

  Area of the plot will be given as 1/4 acre, 1/8 acre, etc.

  Actual age of the stand will be gotten as closely as possible. Pines can be counted back by whorls accurately enough for the purpose. Hardwoods in even-aged stands should have an overtopped tree bored at stump height to check ages. In uneven-aged stands the range of ages should be given.

  Economic age is used for stands which, at some period, have grown under an overwood. The figure given is based on the age which would have been required to reach present size if the stand had been free to grow.

  Density class is an ocular estimate of degree of stocking. Fully stocked stands are called density class I, medium stocked one II and understocked III.

  Site class is also largely based on ocular estimates of the relative growth and development of the species occupying the sites. Three classes are used and, in general, it can be said that the west slope on the east side of Tom Swamp Pond is site I, most of Prospect Hill II, and the sandy or gravelly eskers in Tom Swamp VII site III. The seepage areas in all blocks are apt to approach site I if not too wet.

  Form is simply used to designate whether a stand is even-aged (E.A.), uneven-aged (U.A.) or two-storied.

  Form class is the arbitrary group of absolute form-quotient units into which a given stand falls. These classes are estimated in five-unit classes, i.e. .60, .65 etc. Form classes in white pine can be estimated by use of the crown indexes and dead lengths in Harvard Forest Bulletin 13 until the cruiser becomes enough accustomed to estimating by means of age and density of stocking. As a guide, the open grown, 50-year-old white pines in the north end of the Adams-Fay lot are in form class 50 while the older, densely grown ones between the strip cuttings in the south end of the lot are in class 72. With all hardwoods except gray birch the average form class of trees 7" and over is 65 (Hawley and Wheaton, 1926), with the trend indicated to be slightly upward for smaller sizes but anything measured of the better hardwoods can be assumed to fall in this class. Gray birch falls between form classes .55 and .60, being closer to .60.

  Quality for pine stands is designated as "better than box," "box," and "poor box" and the hardwoods as "sawtimber" or "cordwood."

  Ground cover is described to give an extensive picture of the wildlife food production in the stands. Ground cover should first be described as "dense," medium," "sparse" or lacking and then the species included should be listed in order of abundance. Whenever possible, plants should be identified to species.

  Advance growth as described is, of course, the guide as to what may be expected as the next crop and as to treatment needed. It should be described first as "dense," "medium, " spars" or lacking and then the species should be listed in order of abundance.

  Silvicultural condition and treatment is used to describe the stand in general terms as to what has been done and what is needed. This is one of the most important pieces of information to be gotten and, accordingly, should not be slighted.

  Ring width is used in mature stands to denote whether the average tree is making appreciatble growth. A boring is made at or near breast height to a depth of around one inch and the ring widths for the last ten years marked in the space provided on the plot sheet with the bark indicated as a longer line, thus: '''''''| . After the current year's growth has begun, neglect that and place the bark mark at the start of this growth.

  Remarks is used for anything pertinent that occurs to the cruiser by way of description or needed treatment.

  Tally of the timber on the plot is by means of diameters taken with a tape and heights are gotten to the nearest five-foot class [minimum diameter recorded = 2 inches; trees tallied by species, 1" diameter class and 5' height class]. A Faustmann hypsometer or Abney graduated in per cent is used for checking heights and for getting the cruiser accustomed to estimating heights accurately. All trees are listed by species.

  Computation of Tally

  Volume Tables (all cubic foot). Better hardwoods - Hawley and Wheaton, F.C. 65. Cordwood - Red maple, Cook, Mass. Table; Gray birch, Hawley and Wheaton, F.C. 60. White pine - H.F. Bulletin 13. Hemlock - Merrill. Spruce - H.F. Bulleting 19. Red pine - Canadian Table (F. Class).

  Yield Tables. White pine - Cook. Spruce - H.F. Bulletin 19. Hemlock - Merrill and Hawley, 1924. Better hardwoods - Spaeth. Inferior hardwoods - Spaeth.

• Use:

  This dataset is released to the public and may be freely downloaded. Please keep the designated Contact person informed of any plans to use the dataset. Consultation or collaboration with the original investigators is strongly encouraged. Publications and data products that make use of the dataset must include proper acknowledgement. For more information on LTER Network data access and use policies, please see: http://www.lternet.edu/data/netpolicy.html.

• Related datasets: HF037