Effect of compression wood and grain angle on deformations of studs from 22-year-old scots pine trees

2004 ◽  
Vol 19 (sup5) ◽  
pp. 48-54 ◽  
Author(s):  
Mats Warensjö ◽  
Göran Rune
Keyword(s):  
Scots Pine ◽  
Compression Wood ◽  
Grain Angle ◽  
Pine Trees

Strength properties of wind- and snow-damaged stems of Picea sitchensis and Pinus sylvestris in comparison with undamaged trees

1999 ◽  
Vol 29 (5) ◽  
pp. 595-599 ◽  
Author(s):  
A D Cameron ◽  
R A Dunham
Keyword(s):  
Pinus Sylvestris ◽  
Scots Pine ◽  
Compression Wood ◽  
Outer Part ◽  
Sitka Spruce ◽  
Strength Properties ◽  
Picea Sitchensis ◽  
Modulus Of Rupture ◽  
Clear Wood ◽  
Pine Trees

This study compared the strength properties of wood taken from Sitka spruce (Picea sitchensis (Bong.) Carr.) and Scots pine (Pinus sylvestris L.) trees damaged as a result of wind and snow. The spruce trees were located in triplets of stems of similar diameter that had snapped, overturned (i.e., uprooted), or remained undamaged as a result of wind and snow. The pine trees were located in pairs of similar-sized stems that had snapped or remained undamaged. None of the pine trees overturned. Clear wood (wood without knots and sloping grain) from the outer part of the stem of snapped Sitka spruce and Scots pine trees was less stiff (lower modulus of elasticity (MOE)) than wood taken from the same location from overturned (spruce only) or standing trees. Modulus of rupture and density were unaffected. Damaged trees of both species were found to have significantly more compression wood within the test samples in comparison with undamaged trees. These findings suggest that trees that either overturn or snap are bending more than undamaged trees (because of their low MOE) thereby introducing a greater component of crown weight to the overall forces acting on the stem, and that this may be associated with compression wood.

Basal sweep and compression wood in young Scots pine trees

2002 ◽  
Vol 17 (6) ◽  
pp. 529-537 ◽  
Author(s):  
Göran Rune ◽  
Mats Warensjö
Keyword(s):  
Scots Pine ◽  
Compression Wood ◽  
Pine Trees

scholarly journals Interacting effects of insect and ungulate herbivory on Scots pine growth

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Michelle Nordkvist ◽  
Maartje J. Klapwijk ◽  
La rs Edenius ◽  
Christer Björkman
Keyword(s):  
Plant Growth ◽  
Scots Pine ◽  
Growth Response ◽  
Insect Herbivory ◽  
Additive Effects ◽  
Significant Interaction Effect ◽  
Ungulate Herbivory ◽  
Pine Trees ◽  
Multiple Species ◽  
Species Specific

AbstractMost plants are subjected to damage from multiple species of herbivores, and the combined impact on plant growth can be non-additive. Since plant response to herbivores tends to be species specific, and change with repeated damage, the outcome likely depend on the sequence and number of attacks. There is a high likelihood of non-additive effects on plant growth by damage from mammals and insects, as mammalian herbivory can alter insect herbivore damage levels, yet few studies have explored this. We report the growth response of young Scots pine trees to sequential mammal and insect herbivory, varying the sequence and number of damage events, using an ungulate-pine-sawfly system. Combined sawfly and ungulate herbivory had both additive and non-additive effects on pine growth—the growth response depended on the combination of ungulate browsing and sawfly defoliation (significant interaction effect). Repeated sawfly herbivory reduced growth (compared to single defoliation) on un-browsed trees. However, on browsed trees, depending on when sawfly defoliation was combined with browsing, trees exposed to repeated sawfly herbivory had both higher, lower and the same growth as trees exposed to a single defoliation event. We conclude that the sequence of attacks by multiple herbivores determine plant growth response.

Freeze-preservation of buds from Scots pine trees

1991 ◽  
Vol 27 (1) ◽  
pp. 89-93 ◽  
Author(s):  
Tero Kuoksa ◽  
Anja Hohtola
Keyword(s):  
Scots Pine ◽  
Pine Trees

scholarly journals Scots pine (Pinus sylvestris) dynamics in the Welsh Marches during the mid to late-Holocene

The Holocene ◽  
2021 ◽  
pp. 095968362199465
Author(s):  
Dael Sassoon ◽  
William J Fletcher ◽  
Alastair Hotchkiss ◽  
Fern Owen ◽  
Liting Feng
Keyword(s):  
Pinus Sylvestris ◽  
Scots Pine ◽  
Late Holocene ◽  
British Isles ◽  
Loss On Ignition ◽  
Peat Core ◽  
New Information ◽  
Pine Trees ◽  
Pollen Records

Around 4000 cal yr BP, Scots pine ( Pinus sylvestris) suffered a widespread demise across the British Isles. This paper presents new information about P. sylvestris populations found in the Welsh Marches (western central Britain), for which the long-term history and origins are poorly known. Two new pollen records were produced from the Lin Can Moss ombrotrophic bog (LM18) and the Breidden Hill pond (BH18). The LM18 peat core is supported by loss-on-ignition, humification analysis and radiocarbon dating. Lead concentrations were used to provide an estimated timeframe for the recent BH18 record. In contrast to many other Holocene pollen records from the British Isles, analysis of LM18 reveals that Scots pine grains were deposited continuously between c. 6900–300 cal yr BP, at frequencies of 0.3–5.4%. It is possible that individual Scots pine trees persisted through the wider demise on thin soils of steep drought-prone crags of hills or the fringes of lowland bogs in the Welsh Marches. At BH18, the record indicates a transition from broadleaved to mixed woodland, including conifer species introduced around AD 1850 including Picea and Pinus. The insights from BH18 suggest that the current populations may largely be the result of planting. Comparison of the LM18 findings with other regional pollen records highlights consistent patterns, including a Mid-Holocene maximum (ca. 7000 cal yr BP), long-term persistence at low pollen percentages and a Late-Holocene minimum (ca. 3000 cal yr BP). These distinctive trends encourage further studies on refugial areas for Scots pine in this region and elsewhere.

scholarly journals CHRONIC IRRADIATION OF SCOTS PINE TREES (PINUS SYLVESTRIS) IN THE CHERNOBYL EXCLUSION ZONE: DOSIMETRY AND RADIOBIOLOGICAL EFFECTS

2011 ◽  
Vol 101 (4) ◽  
pp. 393-408 ◽  
Author(s):  
Vasyl I. Yoschenko ◽  
Valery A. Kashparov ◽  
Maxim D. Melnychuk ◽  
Svjatoslav E. Levchuk ◽  
Yulia O. Bondar ◽  
...  
Keyword(s):  
Pinus Sylvestris ◽  
Scots Pine ◽  
Chronic Irradiation ◽  
Exclusion Zone ◽  
Pine Trees ◽  
Radiobiological Effects

scholarly journals Chemodiversity of a Scots pine stand and implications for terpene air concentrations

2012 ◽  
Vol 9 (2) ◽  
pp. 689-702 ◽  
Author(s):  
J. Bäck ◽  
J. Aalto ◽  
M. Henriksson ◽  
H. Hakola ◽  
Q. He ◽  
...  
Keyword(s):  
Scots Pine ◽  
Atmospheric Chemistry ◽  
Bimodal Distribution ◽  
Atmospheric Modeling ◽  
Emission Data ◽  
Intermediate Group ◽  
Pine Trees ◽  
Seed Origin ◽  
Atmospheric Concentrations ◽  
Air Concentrations

Abstract. Atmospheric chemistry in background areas is strongly influenced by natural vegetation. Coniferous forests are known to produce large quantities of volatile vapors, especially terpenes. These compounds are reactive in the atmosphere, and contribute to the formation and growth of atmospheric new particles. Our aim was to analyze the variability of mono- and sesquiterpene emissions between Scots pine trees, in order to clarify the potential errors caused by using emission data obtained from only a few trees in atmospheric chemistry models. We also aimed at testing if stand history and seed origin has an influence on the chemotypic diversity. The inherited, chemotypic variability in mono- and sesquiterpene emission was studied in a seemingly homogeneous 48 yr-old stand in Southern Finland, where two areas differing in their stand regeneration history could be distinguished. Sampling was conducted in August 2009. Terpene concentrations in the air had been measured at the same site for seven years prior to branch sampling for chemotypes. Two main compounds, α-pinene and Δ3-carene formed together 40–97% of the monoterpene proportions in both the branch emissions and in the air concentrations. The data showed a bimodal distribution in emission composition, in particular in Δ3-carene emission within the studied population. 10% of the trees emitted mainly α-pinene and no Δ3-carene at all, whereas 20% of the trees where characterized as high Δ3-carene emitters (Δ3-carene forming >80% of total emitted monoterpene spectrum). An intermediate group of trees emitted equal amounts of both α-pinene and Δ3-carene. The emission pattern of trees at the area established using seeding as the artificial regeneration method differed from the naturally regenerated or planted trees, being mainly high Δ3-carene emitters. Some differences were also seen in e.g. camphene and limonene emissions between chemotypes, but sesquiterpene emissions did not differ significantly between trees. The atmospheric concentrations at the site were found to reflect the species and/or chemodiversity rather than the emissions measured from any single tree, and were strongly dominated by α-pinene. We also tested the effect of chemodiversity on modeled monoterpene concentrations at the site and found out that since it significantly influences the distributions and hence the chemical reactions in the atmosphere, it should be taken into account in atmospheric modeling.

scholarly journals Estimation of crown and canopy cover from airborne lidar data

2010 ◽  
Vol 52 (1) ◽  
pp. 5-17 ◽  
Author(s):  
Mait Lang
Keyword(s):  
Norway Spruce ◽  
Scots Pine ◽  
Stand Structure ◽  
Canopy Cover ◽  
Airborne Lidar ◽  
Silver Birch ◽  
Lidar Data ◽  
Crown Cover ◽  
Pine Trees ◽  
Airborne Lidar Data

Metsa katvuse ja liituse hindamine lennukilt laserskanneriga Tests were carried out in mature Scots pine, Norway spruce and Silver birch stands at Järvselja, Estonia, to estimate canopy cover (K) and crown cover (L) from airborne lidar data. Independent estimates Kc and Lc for K and L were calculated from the Cajanus tube readings made on the ground at 1.3 m height. Lidar data based cover estimates depended on the inclusion of different order returns significantly. In all the stands first order return based estimate K1 was biased positively (3-10%) at the reference height of 1.3 m compared to ground measurements. All lidar based estimates decreased with increasing the reference height. Single return (Ky) and all return (Kk) based canopy cover estimates depended more on the sand structure compared to K1. The ratio of all return count to the first return count D behaved like crown cover estimate in all stands. However, in spruce stand D understimated Lc significantly. In the Scots pine stand K1(1.3) = 0.7431 was most similar canopy cover estimate relative to the ground estimate Kc = 0,7362 whereas Ky(1.3) and Kk(1.3) gave significant underestimates (>15%) of K. Caused by the simple structure of Scots pine stand - only one layer pine trees, the Cajanus tube based canopy cover (Kc), crown cover (Lc) and lidar data based canopy density D(1.3) values were rather similar. In the Norway spruce stand and in the Silver birch stand second layer and regeneration trees were present. In the Silver birch stand Kk(1.3) and Ky(1.3) estimated Kc rather well. In the Norway spruce stand Ky(1.3) and K1(1.3) were the best estimators of Kc whereas Kk(1.3) underestimated canopy cover. Lidar data were found to be usable for canopy cover and crown cover assessment but the selection of the estimator is not trivial and depends on the stand structure.

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