Growth and form responses to pre-commercial thinning regimes in aerially seeded jack pine stands: 5th year results

In 1986, a thinning trial was established in a 9-year-old jack pine stand near Dryden, Ontario. Four blocks consisting of five thinning regimes (1 m × 1 m, 1.5 m × 1.5 m, 2 m × 2 m, 2.5 m × 2.5 m, 3 m × 3 m) and a control plot were established using a randomized complete block design. Once thinned, a series of measurements were taken in 1986 and repeated in 1991 to determine growth and form responses. Results identified highly significant responses for DBH growth and individual stem volume growth. Height response did not vary among the spacing levels. Changes in crown dimensions and stem taper were used to evaluate form responses to thinning. A highly significant decline in all form variables was found in response to increased spacing. Although the increased growth in individual trees provides an opportunity to produce a wider array of products, it appears to be at a cost of reduced form characteristics. Specific management implications for the Dryden Crown Forest are discussed. Key words: jack pine, pre-commercial thinning, growth and form responses

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Stand structure and growing space efficiency following thinning in an even-aged Douglas-fir stand

Canadian Journal of Forest Research ◽

10.1139/x88-132 ◽

1988 ◽

Vol 18 (7) ◽

pp. 859-866 ◽

Cited By ~ 56

Author(s):

K. L. O'Hara

Keyword(s):

Stand Structure ◽

Volume Growth ◽

Basal Area ◽

Stand Density ◽

Douglas Fir ◽

Stem Volume ◽

Projection Area ◽

Individual Tree ◽

Space Efficiency ◽

Individual Trees

The growth of individual trees from four thinning treatments in a 64-year-old Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) stand was analyzed to determine desirable residual stand structures after thinning. Dominant and codominant trees had the highest individual tree stem volume growth rates over the previous 5 years, and accounted for most stand volume growth in thinned and unthinned stands. Two measures of growing space, crown projection area and sapwood basal area (a surrogate for leaf area), were used to measure how efficiently individual trees used their growing space. Crown classes were useful in characterizing growing space efficiency (volume growth per unit of growing space) only in the unthinned treatment. In thinned treatments, tall trees with medium-sized crowns were most efficient, while in the unthinned treatment, tall trees with relatively large crowns were most efficient. A large crown in an unthinned stand was comparable in size to a medium-sized crown in a thinned stand. Results suggest growing space is not limiting individual tree growth in thinned stands and that thinning to a particular stand structure is more appropriate than thinning to a particular level of stand density.

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Critical period of interspecific competition for northern conifers associated with herbaceous vegetation

Canadian Journal of Forest Research ◽

10.1139/x99-055 ◽

1999 ◽

Vol 29 (7) ◽

pp. 890-897 ◽

Cited By ~ 64

Author(s):

Robert G Wagner ◽

Gina H Mohammed ◽

Thomas L Noland

Keyword(s):

Interspecific Competition ◽

Critical Period ◽

Black Spruce ◽

Volume Growth ◽

Jack Pine ◽

Red Pine ◽

Volume Index ◽

Stem Volume ◽

White Pine ◽

Herbaceous Vegetation

Using critical-period analysis, we examined the temporal effects of interspecific competition from herbaceous vegetation on seedlings of jack pine (Pinus banksiana Lamb.), red pine (Pinus resinosa Ait.), eastern white pine (Pinus strobus L.), and black spruce (Picea mariana (Mill.) BSP) during the first 5 years after planting. The critical period is the time period during stand development when interspecific competition reduces tree growth. We found both similarities and differences in responses among tree species. Gains in stem volume index associated with increasing duration of vegetation control (expressed by weed-free curves) differed among species. In contrast, declines in stem volume index with increasing duration of competition after planting (expressed by weed-infested curves) were equal among species. Critical periods for stem volume index were shorter for shade-intolerant jack and red pine (1 and 2 years after planting) than for more shade-tolerant white pine and black spruce (1-3 years for spruce and 1-4 years for white pine). Intolerant species had greater absolute stem volume growth, but smaller relative declines from continuous association with herbaceous vegetation (85, 81, 78, and 67% for white pine, black spruce, red pine, and jack pine, respectively). Herbaceous vegetation did not affect survival and had a variable influence on height growth of all species.

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Tree size, biomass, and volume growth of twelve 34-year-old Ontario jack pine provenances

Canadian Journal of Forest Research ◽

10.1139/x85-183 ◽

1985 ◽

Vol 15 (6) ◽

pp. 1129-1136 ◽

Cited By ~ 4

Author(s):

S. Magnussen ◽

V. G. Smith ◽

C. W. Yeatman

Keyword(s):

Volume Growth ◽

Tree Height ◽

Stem Bark ◽

Jack Pine ◽

Tree Size ◽

Stem Volume ◽

Strong Negative Correlation ◽

Stem Wood ◽

Volume Production ◽

Branch Wood

Tree size and aboveground biomass in twelve 34-year-old Ontario jack pine (Pinusbanksiana Lamb.) provenances growing at Petawawa National Forestry Institute (Chalk River, Ontario) was negatively correlated with latitude of origin. The best provenance exceeded the local provenance in tree height and diameter by approximately 10%. The pattern of geographical variation was stable over time, making general and sound predictions of provenance growth based on juvenile performance feasible. Persistent differences among some geographically close provenances indicated the potential for genetic improvement by selecting the best populations within site regions. The results demonstrated have important implications for jack pine breeding and improvement strategies at the provenance level. The provenance averages of aboveground ovendry weight per tree ranged from 44 to 79 kg. The aboveground tree biomass was distributed as follows in seven analyzed provenances: stem wood, 78%; stem bark, 8%; branch wood, 8%; needles, 5%; cones, 1%. Variation in average stemwood mass among provenances was less than the variation in average stem volume because of a strong negative correlation on a single tree basis between stem volume and stem wood density. The mean annual volume and biomass accretion per hectare in the best provenances averaged 10 m3 and 4 t, respectively. Total stem volume production per hectare varied exponentially with tree height. Mean annual stem volume increment of the best provenances exceeded that of the slowest growing provenances by 22–40%.

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Vertical patterns in specific volume increment along stems of dominant jack pine (Pinus banksiana) and black spruce (Picea mariana) after thinning

Canadian Journal of Forest Research ◽

10.1139/x2012-029 ◽

2012 ◽

Vol 42 (4) ◽

pp. 733-748 ◽

Cited By ~ 25

Author(s):

Venceslas Goudiaby ◽

Suzanne Brais ◽

Frank Berninger ◽

Robert Schneider

Keyword(s):

Picea Mariana ◽

Specific Volume ◽

Pinus Banksiana ◽

Black Spruce ◽

Mass Density ◽

Volume Growth ◽

Jack Pine ◽

Stem Volume ◽

Volume Increment ◽

Foliage Density

Jack pine ( Pinus banksiana Lamb.) and black spruce ( Picea mariana (Mill.) B.S.P.) total stem volume increment and vertical growth distribution after thinning were quantified and related to foliage biomass, foliage density, and growth efficiency (GE) (stem to foliage biomass ratio). Significant positive stem volume increments were observed following thinning for jack pine (3 years after) and black spruce (4 years after). Both species reacted differently in terms of the distribution in specific volume increments (SVI) (annual stem volume increment to cambial surface ratio): (i) for jack pine, an increase in SVI was first observed at the base of the tree, with the increase moving upwards, showing that the taper was likely to increase following thinning and (ii) for black spruce, the vertical distribution of SVI was constant, leading to no modifications in stem taper. For jack pine, total stem volume growth was related to an increase in GE and a greater foliage biomass at midcrown, with foliage density staying constant. For black spruce, however, no changes in GE, foliage biomass, and foliage mass density were observed.

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Effects of precommercial thinning on tree growth and lumber quality in a jack pine stand in New Brunswick, Canada

Canadian Journal of Forest Research ◽

10.1139/x05-307 ◽

2006 ◽

Vol 36 (4) ◽

pp. 945-952 ◽

Cited By ~ 44

Author(s):

S Y Zhang ◽

Gilles Chauret ◽

D Edwin Swift ◽

Isabelle Duchesne

Keyword(s):

New Brunswick ◽

Tree Growth ◽

Volume Growth ◽

Jack Pine ◽

Modulus Of Rupture ◽

Stem Volume ◽

Stand Age ◽

Bending Properties ◽

Precommercial Thinning ◽

Thinning Intensity

A naturally regenerated jack pine (Pinus banksiana Lamb.) trial established in 1966 in New Brunswick was studied to determine how three precommercial thinning intensities (1.22 m × 1.22 m, 1.52 m × 1.52 m, and 2.13 m × 2.13 m) and a control (154 trees in total) affected tree growth and lumber quality. Mild (thinned to 1.22 m) and moderate (1.52 m) thinning had a modest impact on tree growth after 34 years (stand age 59). However, intensive thinning (2.13 m, or 2212 stems/ha) increased tree height by 13.1% compared with the control, whereas tree diameter and merchantable stem volume per tree increased by >20% and >75%, respectively. Yields of No. 2 and Better increased slightly with increasing thinning intensity, but lumber bending properties decreased with increasing thinning intensity. There was, respectively, >20% and >15% difference in lumber strength (modulus of rupture) and stiffness (modulus of elasticity) between the mild (1.22 m) and intensive (2.13 m) thinnings. Intensive precommercial thinning (2.13 m) is recommended for increased volume growth, but rotation age (>59 years) should not be reduced if lumber bending properties are of concern.

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Twelfth-year response of Douglas-fir to area of weed control and herbaceous versus woody weed control treatments

Canadian Journal of Forest Research ◽

10.1139/x06-126 ◽

2006 ◽

Vol 36 (10) ◽

pp. 2464-2473 ◽

Cited By ~ 34

Author(s):

Robin Rose ◽

Lee S Rosner ◽

J Scott Ketchum

Keyword(s):

Weed Control ◽

Stand Structure ◽

Volume Growth ◽

Woody Species ◽

Douglas Fir ◽

Stem Volume ◽

Coast Range ◽

Vegetation Control ◽

Hardwood Species ◽

Individual Trees

Coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) response to eight weed control treatments was measured 12 years after planting at two Oregon sites. Treatments included four areas of weed control around individual trees (0.375, 1.49, 3.35, and 5.95 m2), no weed control (check), total vegetation control, control of herbaceous competition only, or control of woody competition only. Douglas-fir growth and woody-species invasion differed between the Coast Range site (Summit) and the Cascade Range foothills site (Marcola). Woody species reinvasion was more intense at Summit, with Douglas-fir cumulative mortality in the check treatment reaching 23% in year 12. Woody-only control improved Douglas-fir growth at Summit but had no significant effect on growth at Marcola. Total vegetation control had a profound effect on stem volume growth 12 years after planting. At Summit, total vegetation control resulted in a 355% increase in volume per hectare relative to the check. At Marcola the increase was only 63%. At Summit, growth increased with each increase in area of weed control, whereas at Marcola growth increased with increasing area of weed control up to 3.35 m2 of control. Results suggest that much of the gain in volume growth attributable to weed control may be lost if weed-control treatments are not highly efficacious. The differential response to woody control indicates that its benefit at a given site is strongly related to the abundance of competitive hardwood species, which may be predicted from the preharvest stand structure and vegetation community.

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Influence of Stem Taper on the Yield of Black Spruce Stands and Trees Following Commercial Thinning

Forests ◽

10.3390/f10111024 ◽

2019 ◽

Vol 10 (11) ◽

pp. 1024 ◽

Cited By ~ 1

Author(s):

Manon Vincent ◽

Cornelia Krause ◽

Ahmed Koubaa

Keyword(s):

Treatment Effect ◽

Black Spruce ◽

Growth Increment ◽

Tree Level ◽

Stem Volume ◽

Stand Volume ◽

Commercial Thinning ◽

Volume Increment ◽

Individual Trees ◽

Stem Shape

In this work, we examine the effects of commercial thinning on stand volume and individual stem form in nine naturally regenerated black spruce (Picea mariana (Mill.) B.S.P.) stands. We compared these study sites with controls in the commercial boreal forest of northern Quebec, Canada. At stand level, dendrochronological data provided insight into changes in stand volume ten years after thinning. Analysis of a subsample of six individual trees from each commercially thinned stand and three individual trees from the controls illustrated the role of thinning on stem shape development. Although average volume increased for residual stems in thinned stands slightly more than in the controls (110% versus 106%), the treatment effect stand-level volume increment or stand-level total volume harvested (ten years after treatment) was not statistically significant. Moreover, at tree level, thinning did not significantly affect stem volume increment. However, radial growth increment significantly increased after treatment. Trees from commercially thinned stands showed a significantly higher growth increment along the lower first two-thirds of the stem. Response to thinning at tree level correlated strongly with the size and number of harvested competitors around a residual stem. We conclude that commercial thinning modified wood allocation rather than wood volume and did not affect taper and stem shape. These patterns of post-cutting growth are explained by wood allocation following thinning. After commercial thinning, growth increment is favored at the expense of height growth. As the treatment effect was found at the stem scale rather than at the stand scale, further research is needed in regard to commercial thinning treatments to investigate how to increase productivity at the stand scale.

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Impact of initial spacing and precommercial thinning on jack pine tree growth and stem quality

The Forestry Chronicle ◽

10.5558/tfc81418-3 ◽

2005 ◽

Vol 81 (3) ◽

pp. 418-428 ◽

Cited By ~ 18

Author(s):

Q J Tong ◽

S Y Zhang

Keyword(s):

Tree Growth ◽

Jack Pine ◽

Stem Length ◽

Stem Volume ◽

Positive Effects ◽

Commercial Thinning ◽

Dbh Distribution ◽

Stem Quality ◽

Initial Spacing ◽

The Impact

The objective of this paper was to investigate the impact of initial spacing and pre-commercial thinning (PCT) on tree growth, characteristics and stem quality in plantation-grown jack pine (Pinus banksiana Lamb.) after 58 years of growth. Four spacings including three initial spacings without PCT treatment, i.e., 1.52 × 1.52 m (5 × 5 ft), 2.13 × 2.13 m (7 × 7 ft) and 2.74 × 2.74 m (9 × 9 ft) and one initial spacing with PCT treatment (5 × 5 ft thinned to 7 × 7 ft at age 14), were chosen to analyze diameter at breast height (DBH) distribution, survival, and various tree and stem quality characteristics (e.g., DBH, total tree height, stem volume, crown size, branch, taper, sweep and wobbling). Tree mortality during the first 25 growth years was quite low for all four spacings, while after 25 years, survival for the four spacings rapidly declined. The decrease in survival for spacing 5 × 5 was the steepest, followed by spacings 7 × 7, 9 × 9 and finally the PCT-treated stand. DBH distributions for all four spacings were significantly different from each other, and five years after PCT, the 5 × 5 to 7 × 7 spacings had a similar DBH distribution to that of the constant 7 × 7 spacing. Mean DBHs differed significantly among the initial spacings. The 5 × 5 spacing produced significantly smaller trees than did the other three spacings through the years, and the 9 × 9 spacing produced significantly larger trees. PCT had positive effects on DBH growth, and yielded longer merchantable stems and better stem quality. PCT had little effect on crown development. Initial spacing significantly affected diameter growth, crown width and branch development, commercial stem length and volume, stem taper and stem deformation. Narrower spacing produced smaller but better quality stems. Spacing 7 × 7 had the worst stem quality in terms of overall sweep and wave-like transversal deformation (wobbling). A narrow initial spacing followed by a PCT treatment may provide a compromise solution for both tree growth and stem quality. Key words: Initial spacing, thinning, survival, tree growth, stem quality

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Response of a Scots pine (Pinus sylvestris) stand to application of phosphorus, potassium, magnesium and lime. 3. Foliar nutrient concentrations and stand development

Netherlands Journal of Agricultural Science ◽

10.18174/njas.v41i4.636 ◽

1993 ◽

Vol 41 (4) ◽

pp. 291-307

Author(s):

G. Arnold ◽

A. Van Diest

Keyword(s):

Scots Pine ◽

Volume Growth ◽

Stem Volume ◽

Nutrient Concentrations ◽

Growth Responses ◽

Foliar Nutrient ◽

Foliar Concentrations ◽

Foliar Nutrient Concentrations ◽

Annual Volume ◽

Individual Trees

In 1985-88, a 25-yr-old Scots pine forest in Netherlands was limed and fertilized with P, K and Mg in a factoral design. This paper addresses effects of these treatments on foliar nutrient concentrations and tree growth. Stem volume increments of individual trees were measured. Average annual volume growth was estimated to be about 16 msuperscript 3/ha, which may be a slight underestimation. P and K showed increased foliar concentrations immediately after treatment and were the only elements that significantly increased volume growth in 1988-91. Additional annual volume growth of individual trees brought about by P and K corresponded with 0.9 and 2.2 msuperscript 3/ha, respectively. Foliar Mg and Ca increased later and insignificantly reduced and increased volume growth, respectively. Lime and Mg applications tended to lower foliar N. When absolute foliar concentrations and element ratios were compared to Dutch and German standards, it appeared that application of some of these standards in present research would not always have given a fully correct prediction of growth responses to nutrient additions.

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