Comparison of relative accuracy and time requirement between the caliper, the diameter tape and an electronic tree measuring fork

This study compares the relative accuracy of diameters measured with the caliper, the diameter tape, and the electronic tree measuring fork (ETMF) Tally BoyMC with and without reflector. The time required for the measure and the data entry of diameters to computer for each instrument was also evaluated. Significant differences in mean DBH (diameter outside bark at breast height — 1.3 m above ground) generally occurred among instruments. Nevertheless, even if these differences were significant, they were less than 1 cm for five of the six species tested. For white pine (Pinus strobus L.), however, the use of the ETMF without reflector led to an important overestimation of the DBH in comparison to the caliper, the diameter tape and the ETMF with reflector. The typical fissured bark observed on white pines could probably explain that overestimation. For all species, the addition of the reflector to the ETMF decreased the differences among instruments. The measures taken with the diameter tape were slightly larger than those made with the caliper. In comparison to the diameter tape and the caliper, the ETMF reduced the time required for date collection from 35 to 45%. Key words: diameter measurement, timber inventory

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A geometrical tree volume model based on the location of the centre of gravity of the bole

Canadian Journal of Forest Research ◽

10.1139/x82-033 ◽

1982 ◽

Vol 12 (2) ◽

pp. 215-221 ◽

Cited By ~ 23

Author(s):

Robert R. Forslund

Keyword(s):

Volume Estimation ◽

Diameter Measurement ◽

Stem Form ◽

Total Height ◽

Volume Model ◽

Breast Height ◽

Centre Of Gravity ◽

Geometrical Form ◽

Volume Equation ◽

Diameter Outside Bark

A tree bole model describing a geometrical form in between a paraboloid and cone "paracone" has been developed. The model is based on empirical evidence that the average centre of gravity of aspen (Populustremuloides Michx.) boles without branches lies at 3/10 of the bole height from its base. Outside bark bole volume, V (cubic decimetres), can therefore be estimated nondestructively from the total height, H (metres), and the diameter outside bark, dK (centimetres), measured at a relative height, K, as follows:[Formula: see text]Based on a sample of 70 aspen stems, this equation estimates individual bole volume from total bole length or height and from a single diameter measurement, either at the 3/10 position or at the breast-height position, as accurately as Smalian's formula using seven diameter measurements. Based on the sample, the 3/10 position should be chosen over breast height wherever breast height lies below 20 or above 60% of the total height. It is important that care be taken in the measurement of the diameter due to the sensitivity of the volume equation to diameter variation. In addition to volume estimation, the paracone model provides a comparison profile around which stem form variation within and among species may be observed.

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Operational biomass recovery of small trees: equations for six central Ontario tree species

Canadian Journal of Forest Research ◽

10.1139/cjfr-2014-0429 ◽

2015 ◽

Vol 45 (3) ◽

pp. 372-377 ◽

Cited By ~ 1

Author(s):

Matt Thiel ◽

Nathan Basiliko ◽

John Caspersen ◽

Jeff Fera ◽

Trevor Jones

Keyword(s):

Pinus Strobus ◽

Size Class ◽

Forest Types ◽

White Pine ◽

Breast Height ◽

Biomass Equations ◽

Bioenergy Feedstocks ◽

Biomass Recovery ◽

The Difference ◽

High Degree

Accurate estimates of the amount of biomass that can be recovered at the roadside are needed to make informed decisions about whether to implement an increased utilization harvesting system to supply additional bioenergy feedstocks. Current estimates of recovery are based on total aboveground biomass equations that do not always account for the volume lost to the unharvested stumps or to tops and branches broken during forestry operations. The study took place in a white pine (Pinus strobus L.) mixedwood forest at the Petawawa Research Forest in central Ontario. Equations to describe recoverable biomass were developed from 371 cut and skidded trees, which ranged from 3 to 24 cm in diameter at breast height, across six species. For each species and diameter size class, we evaluated the difference between estimates produced by locally developed equations and those from published equations produced for other locations and forest types. Our recovered biomass estimates were generally higher than the Canadian national averages but within the observed range of published values from across North America. We report that small trees are recovered nearly in their entirety, with little breakage and loss during operations. The high degree of variability among estimates produced by the various equations poses one of the biggest challenges in accurately estimating roadside biomass in an operational setting.

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Effets du brûlage dirigé et du scarifiage sur l'établissement des semis et sur leur interaction avec la végétation concurrente

The Forestry Chronicle ◽

10.5558/tfc71621-5 ◽

1995 ◽

Vol 71 (5) ◽

pp. 621-626 ◽

Cited By ~ 5

Author(s):

Renée Tellier ◽

Luc C. Duchesne ◽

Robert S. McAlpine ◽

Jean-Claude Ruel

Keyword(s):

Survival Rate ◽

Key Words ◽

Seedling Survival ◽

Pinus Strobus ◽

Pinus Resinosa ◽

Red Pine ◽

Fire Intensity ◽

Competition Index ◽

White Pine ◽

Clear Cut

In 1990, a jack pine forest was clear-cut on an 15 ha area and divided into 40 plots. In 1991, ten plots were burned-over under varying conditions to obtain different fire intensities and ten plots were scarified. Each plot was planted in 1992 with red pine (Pinus resinosa Ait.) and white pine (P. strobus L.) seedlings. Survival rate and health of the seedlings was evaluated for the first two years after planting and the non-crop vegetation was assessed using a competition index developed for conifer management in Ontario. Our results show seedling survival rate, health, biomass and height to be improved when planted on burned-over or scarified sites and that fire intensity influences certain of those characteristics. Key words: scarification, fire, Pinus resinosa, Pinus strobus, competition

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An investigation of product form

Canadian Journal of Forest Research ◽

10.1139/x84-137 ◽

1984 ◽

Vol 14 (6) ◽

pp. 768-774 ◽

Cited By ~ 1

Author(s):

P. Roebbelen ◽

V. G. Smith

Keyword(s):

Black Spruce ◽

Jack Pine ◽

Small Sample ◽

Red Pine ◽

Product Form ◽

Regression Equations ◽

White Pine ◽

Total Height ◽

Breast Height ◽

Diameter Outside Bark

Product form (P) of a tree has been defined as the product of diameter-outside-bark at midheight above breast height (d) and total height (H) (P = d × H). It is used along with diameter breast height (D) in product form volume equations (VPF = f(P,D)) for estimating individual tree volumes. It is hypothesized that for each coniferous species, there exists some optimal height at which a diameter measurement can be taken and used in a product form term to estimate the inside-bark volume with minimum error. Regression equations and simpler expressions of the form V = D2 × H × F were developed for red pine (Pinusresinosa Ait.), white pine (Pinusstrobus L.), jack pine (Pinusbanksiana Lamb.), and black spruce (Piceamariana (Mill.) B.S.P.) using six upper diameter locations. The optimal location of the upper diameter was found to be 50% of the total height for red pine and white pine and 47% of total height for jack pine and black spruce. Product form is redefined as P = d* × H where d* = diameter-outside-bark at that average relative height on the tree where d* = (2 × V)/(D × H) as determined from a small sample of scaled trees, for each species and H = total height of tree.

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Chronicle of white pine and red pine research at the Petawawa National Forestry Institute

The Forestry Chronicle ◽

10.5558/tfc70372-4 ◽

1994 ◽

Vol 70 (4) ◽

pp. 372-381 ◽

Cited By ~ 2

Author(s):

W. M. Stiell

Keyword(s):

Key Words ◽

Pinus Strobus ◽

Forest Service ◽

Forest History ◽

Red Pine ◽

White Pine ◽

Eastern White Pine ◽

Forestry Research

Research dealing with eastern white pine (Pinus strobus L.) and red pine (P. resinosa Ait.) at the Petawawa National Forestry Institute is traced from its inception in 1918 to the present. Individual studies are described briefly, together with the names of the scientists who conducted them and the titles of publications which ensued. Key words: Forest history, forestry research, white pine, red pine, Canadian Forest Service, Petawawa National Forestry Institute

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Zones de Vulnérabilité du Pin Blanc à la Rouille Vésiculeuse au Québec

The Forestry Chronicle ◽

10.5558/tfc62024-1 ◽

1986 ◽

Vol 62 (1) ◽

pp. 24-28 ◽

Cited By ~ 6

Author(s):

André Lavallée

Keyword(s):

Key Words ◽

Pinus Strobus ◽

Cronartium Ribicola ◽

White Pine ◽

Pissodes Strobi ◽

Pine Weevil ◽

Blister Rust ◽

White Pine Weevil

Analysis of relevant data for the last 11 years improved the precision of zoning for white pine vulnerability to blister rust in Quebec. The validity of the existing approach for the area under study was confirmed. White pine located in zones 1 and 2 usually indicated less than 15% stem infections by the blister rust. Distribution of the white pine weevil damage in the zones is presented. Key words: Pinus strobus L., Cronartium ribicola J.C. Fisher, Pissodes strobi Peck, blister rust vulnerability.

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