scholarly journals Crown development of beech crop trees under different thinning regimes

2017 ◽  
Vol 63 (No. 4) ◽  
pp. 173-181
Author(s):  
Štefančík Igor
Keyword(s):  
Surface Area ◽  
Basal Area ◽  
Stand Age ◽  
Projection Area ◽  
Crown Width ◽  
Stem Quality ◽  
Ca 50 ◽  
Crown Thinning ◽  
Crown Projection Area ◽  
Selection Of

Crop trees are the main bearers of qualitative and value production of the stands. Although the number and production of the mentioned trees are affected by various factors, crown development by means of the thinning regime can be considered as very significant. The paper aims at the comparison of crop trees in homogeneous beech (Fagus sylvatica Linnaeus) stands, which were managed by three different management or thinning regimes for a long period (ca. 50 years): (i) heavy thinning from below (C grade according to the German forest research institutes released in 1902), (ii) Štefančík’s free crown thinning, (iii) without interventions (control). Selection of crop trees was carried out at the beginning of research using the best stem quality, diameter and height dimension and regular spacing). In this paper only the last assessment of crop trees aged from 83 to 105 years including 23 subplots established across the Slovakian territory was analysed. The highest number of crop trees has been reached in forests where Štefančík’s free crown thinning was applied. The proportion of these trees on subplots with the mentioned type of crown thinning was 61% out of the basal area at stand age of 100 years. A much lower proportion was found on subplots managed by thinning from below (32%) and on control ones (20%). Crown parameters (crown width, crown ratio, crown projection area, crown surface area and volume) showed the most appropriate values on subplots where Štefančík’s free crown thinning was used. It was: 8.36 m (crown width), 0.50 (crown ratio), 56.84 m<sup>2</sup> (crown projection area), 289.56 m<sup>2</sup> (crown surface area), and 481.75 m<sup>3</sup> (volume). Based on the results obtained after almost 50 years of systematic investigations, the mentioned thinning method was recommended for beech forests.

scholarly journals Slenderness of pedunculate oak (Quercus robur L.) according to biosocial position

2018 ◽  
Vol 73 (3) ◽  
pp. 37-43
Author(s):  
ZDZISŁAW KACZMARSKI ◽  
KATARZYNA MASTERNAK ◽  
MATEUSZ JARMUŁ
Keyword(s):  
Basal Area ◽  
Tree Height ◽  
Projection Area ◽  
Pedunculate Oak ◽  
Single Tree ◽  
Crown Length ◽  
Crown Width ◽  
Growth Space ◽  
Oak Tree ◽  
Crown Projection Area

The paper presents results of an analysis of pedunculate oak slenderness. The dependence between slenderness of the oak tree and dimensions of the trunk and the crown dimensions of a single tree were examined. The biosocial position of each tree was determined based on the Kraft’s classification criteria. Following dimensions were measured for each tree: height, height of base of live crown, crown radius, diameter at breast height. The following crown parameters related to the growth space of a single tree were determined: crown length, crown width, crown projection area, space of a single tree, Seebach’s growth space number, crown projection area to basal area ratio, crown spread. Based on the obtained results, the following was found: biosocial position of the oak tree in vertical structure of the stand has significant impact on the size of the tree slenderness; the slenderness increases with deterioration of the biosocial position of the tree, but it decreases with the increase in the value of the tree’s measurement characteristics and the measures of its crown. 

TRIPLOID APPLE VARIETIES OF SUMMER RIPENING SELECTION VNIISPK ON CLONAL ROOTSTOCK 54-118

1970 ◽  
pp. 34-36
Author(s):  
А. M. Galasheva ◽  
Е. N. Sedov
Keyword(s):  
Tree Height ◽  
Projection Area ◽  
Cross Sectional ◽  
Crown Width ◽  
Crown Volume ◽  
The World ◽  
Apple Cultivars ◽  
Crown Projection Area ◽  
Academy Of Sciences ◽  
First Time

For the first time in the world and in Russia, Academician of the Russian Academy of Sciences, breeder Evgeny Nikolaevich Sedov created a series of triploid apple cultivars from intervalent crosses 2х × 4х. Triploid apple cultivars bear fruit more regularly, have higher self-fruitfulness and have fruits of high marketability. The article presents data on the study of triploid apple cultivars of the summer ripening period of the VNIISPK breeding - Augusta, Daryona, Maslovskoye, Osipovskoye, Zhilinskoye, Spasskoye and Yablochny Spas as well as the control Canadian cultivar Melba on a semi-dwarf clone rootstock 54-118. Maslovskoye, Zhilinskoye, Spasskoye and Yablochny Spas have immunity to scab. The orchard was planted in 2014, the garden planting scheme was 5 x 2 m. The indicators of the growth force (tree height, crown width and stem diameter) and the yield of trees were studied. At the age of six, the trees of triploid cultivars reached a height of 2.2 m (Maslovskoye) to 3.0 m (Yablochny Spas) on a semi-dwarf rootstock 54-118. The highest indicators of crown volume (3.3-5.3 m3), crown projection area (4.2-5.3 m2) and the cross-sectional area of the stem (46.5-52.8 cm2) were in Osipovskoye, Yablochny Spas, Zhilinskoye and Spasskoye. The highest yield in an average of three years was given by triploid scab-immune apple cultivars on a semi-dwarf rootstock 54-118: Maslovskoye, Zhilinskoye, Spasskoye and Yablochny Spas.

The effect of local stand structure on growth and growth efficiency in heterogeneous stands of ponderosa pine and lodgepole pine in central Oregon

2004 ◽  
Vol 34 (11) ◽  
pp. 2217-2229 ◽  
Author(s):  
Douglas B Mainwaring ◽  
Douglas A Maguire
Keyword(s):  
Leaf Area ◽  
Ponderosa Pine ◽  
Lodgepole Pine ◽  
Volume Growth ◽  
Basal Area ◽  
Growth Efficiency ◽  
Projection Area ◽  
Sapwood Area ◽  
Negative Effect ◽  
Crown Projection Area

Basal area and height growth were analyzed for individual trees in uneven-aged ponderosa pine (Pinus ponderosa Dougl. ex Laws.) and lodgepole pine (Pinus contorta Dougl. ex. Loud.) stands in central Oregon. Basal area growth was modeled as a function of other stand and tree variables to address three general objectives: (1) to compare the predictive ability of distance-dependent versus distance-independent stand density variables; (2) to determine the degree to which small trees negatively affect the growth of overstory trees; and (3) to test for differences in growth efficiency between species and between indices of spatial occupancy used to define efficiency (area potentially available, crown projection area, and a surrogate for total tree leaf area). Distance-dependent variables were found to improve growth predictions when added to models with only distance-independent variables, and small trees were found to have a quantifiably negative effect on the growth of larger trees. While volume growth efficiency declined with increasing levels of spatial occupancy for lodgepole pine, ponderosa pine volume growth efficiency was greatest at the highest levels of crown base sapwood area and crown projection area. The behavior in ponderosa pine resulted from the previously recognized correlation between tree height and total leaf area or crown size. The final statistical models distinguished between the positive effect of relative height and the negative effect of increasing tree size.

scholarly journals Effects of heavy thinnings on the increment and selection of trees for tending in Norway spruce monoculture in natural hazard conditions

2017 ◽  
pp. 31-54
Author(s):  
Martin Bobinac ◽  
Sinisa Andrasev ◽  
Andrijana Bauer-Zivkovic ◽  
Nikola Susic
Keyword(s):  
Norway Spruce ◽  
Growth Stage ◽  
Natural Hazard ◽  
Basal Area ◽  
Growth Potential ◽  
Stand Age ◽  
Diameter Increment ◽  
Volume Increment ◽  
Selection Of ◽  
Area And Volume

The paper studies the effects of two heavy selection thinnings on the increment of Norway spruce trees exposed to ice and snow breaks in eastern Serbia. In a thinning that was carried out at 32 years of age, 556 candidates per hectare were selected for tending, and at the age of 40, of the initial candidates, 311 trees per hectare (55.9%) were selected as future trees. In all trees at 41-50 age period, diameter increment was higher by 31%, basal area increment by 64% and volume increment by 67% compared to 32-40 age period. The collective of indifferent trees is significantly falling behind compared to future trees in terms of increment values in both observed periods. However, the value of diameter, basal area and volume increments, of the collective of "comparable" indifferent trees are lower in comparison to the values of increments of future trees by 10-15% in the 32-40 age period, and by 15-21% in the 41-50 age period and there are no significant differences. The results show that heavy selective thinnings, initially directed at a larger number of candidates for tending at stand age that does not differ much from the period of carrying out first "commercial" thinnings, improve the growth potential of future and indifferent trees, where it is rational to do the tree replacement for the final crop in "susceptible" growth stage to snow and ice breaks.

Crown efficiency in a loblolly pine (Pinus taeda) spacing experiment

1998 ◽  
Vol 28 (9) ◽  
pp. 1344-1351 ◽  
Author(s):  
Hubert Sterba ◽  
Ralph L Amateis
Keyword(s):  
Pinus Taeda ◽  
Loblolly Pine ◽  
Basal Area ◽  
Tree Height ◽  
Projection Area ◽  
Individual Tree ◽  
Dominant Height ◽  
Crown Projection Area ◽  
Pinus Taeda L ◽  
Crown Closure

Crown efficiency was first defined by Assmann (1961. Waldertragskunde. BLV, München) as individual tree volume increment per unit of crown projection area. He hypothesized that within a given crown class, smaller crowns are more efficient because their ratio between crown surface and horizontal crown projection is higher. Data from a loblolly pine (Pinus taeda L.) spacing experiment were used to test if this hypothesis also holds in young loblolly pine stands and, if so, to determine if it explains the increment differences between spacings in the spacing experiment. Using individual tree height relative to plot dominant height to describe crown class, within-plot regression showed that crown efficiency decreased with crown size for trees below dominant height. This relationship was much less pronounced than indicated from Assmann's examples, although the crown surface to crown projection ratio behaved in the same way as Assmann had hypothesized. Crown efficiency as well as the crown surface to crown projection area ratio decreased with increasing density. Basal area increment per hectare increased until total crown closure approached 130% and then stayed constant. This major impact of total crown coverage brings into question the usefullness of crown efficiency as an indicator for unit area growth.

scholarly journals The Efficiency of The Tree Crown in The Expression of Growth For Pinus Brutia Ten Trees Growing in Atrush Region Northern Iraq

2021 ◽  
Vol 910 (1) ◽  
pp. 012008
Author(s):  
Mohammad Asim Saeed Al-Ali ◽  
Mutaz Sharif Omar Al-Hamdani
Keyword(s):  
Nonlinear Equation ◽  
Basal Area ◽  
Growth Efficiency ◽  
Projection Area ◽  
Natural Forests ◽  
Pinus Brutia ◽  
Northern Iraq ◽  
Independent Variable ◽  
Crown Projection Area

Abstract The study was conducted on Pinus brutia Ten. trees growing in Atrosh region northern Iraq, which are natural forests of different age. We have taken different measurements of (200) trees to estimate the growth efficiency in both basal area and volume depending on crown projection area of the tree as independent variable. Several linear and nonlinear equations have been obtained through which we can estimate growth and know the role of each of these elements in growth efficiency. For Crown efficiency depending on the basal area (CEBg) denoting the crown projection area (CPA) the nonlinear equation {CEBg=-0.9996+(CPA)-000009851} was chosen, as R2 (72.52) and SE (0.00002 ) and D-W (1.87). We also found The efficiency of the crown depending on the growth of base area (CEBg) denoting the of the crown projection area (CPA) and the height of the tree (H). Also the nonlinear equation was chosen depending on the scales used {CEBg=-1.99964+(CPA)-000009904 +(H)000001599} was the value of R2 (75.77), SE (0.00002) and D-W (1.81).For Crown efficiency depending on the growth in volume (CEVg) in terms of Crown projection area (CPA) the nonlinear equation{CEVg=-0.998015+(CPA)-0 0004362} was chosen as R2(70.11) and standard error SE (0.0001) ) and D-W (1.53), we also found Crown efficiency depending on the growth in volume depending on crown projection area and the height of the tree, the nonlinear equation{CEVg=- 1.9992+(CPA)-0 0005513+(H)00007631} was chosen which the value of R2 (69.44), SE (0.0001) and D-W ( 1.55 ).

scholarly journals The current growth increment of pine tree stands comprising three different age classes

2013 ◽  
Vol 74 (2) ◽  
pp. 93-100 ◽  
Author(s):  
Katarzyna Kaźmierczak
Keyword(s):  
Tree Growth ◽  
Basal Area ◽  
Projection Area ◽  
Age Classes ◽  
Single Tree ◽  
Pine Tree ◽  
Crown Length ◽  
Growth Increments ◽  
Growth Space ◽  
Crown Projection Area

Abstract The study presents the results of an analysis of the pine tree growth increments (height increment, dbh increment, basal area increment and volume increment) for a 5-year period. The study involved Scots pine trees of Kraft’s class 1, 2 and 3 (dominant stand) in stands of different age classes (II, III, V) growing in fresh mixed coniferous (BMśw) and fresh coniferous (Bśw) forest habitats. The multivariate analysis of variance was performed to assess the statistical significance of age and dominance of trees within a stand on their increment. The dominance position was classified for each tree using Kraft’s criteria. The following characteristic were also measured: dbh of the trunk in two directions (N-S and W-E), and crown projection area on the basis of the characteristic tree crown points, projected using of a crown projector, characteristic points in tree crowns (7 to 14 on average). The actual height was determined after trees were felled. The following measurements of the single tree growing space were selected and determined: crown projection area - pk (m2), crown diameter - dk (m), Seebach’s growth space number - dk / d1.3, crown projection area to basal area ratio d 2 k / d 2 1.3, crown deflection coefficient dk / h, single tree space ppd = pk·h (m3). We assessed the strength of the relationships between tree growth parameters and tree growth space, crown length, relative crown length and slenderness. Both the age and dominance position of trees within the stand affected the growth increments. The strongest correlation among measured traits was between the 5-year volume increment and decreasing slenderness.

scholarly journals Responses of Root Characteristic Parameters and Plant Dry Matter Accumulation, Distribution and Transportation to Nitrogen Levels for Spring Maize in Northeast China

Agriculture ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 308
Author(s):  
Yang Yu ◽  
Chunrong Qian ◽  
Wanrong Gu ◽  
Caifeng Li
Keyword(s):  
Surface Area ◽  
Nitrogen Fertilizer ◽  
Root Length ◽  
Dry Matter ◽  
Projection Area ◽  
Dry Matter Accumulation ◽  
Characteristic Parameters ◽  
High Nitrogen ◽  
Nitrogen Levels ◽  
Matter Transport

Improving nitrogen use efficiency is a significant scientific problem to be solved. Two maize hybrids JD27 (Jidan 27) and SD19 (Sidan 19) were selected to study the effects of nitrogen levels on root characteristic parameters and plant dry matter accumulation, distribution and transportation. We set five different nitrogen levels, which were nitrogen deficiency (000N), low nitrogen (075N), medium nitrogen (150N), high nitrogen (225N) and excessive nitrogen (300N). The results showed that the root length and root surface area of JD27 were significantly higher than those of SD19 under 075N. With the increase of nitrogen levels, the root difference among varieties gradually decreased. The root length, projection area, total surface area and total volume reached the maximum values at silking stage. The average root diameter kept stable or decreased slowly with the growth stage. The dry matter accumulation of JD27 was higher than that of SD19 at all growth stages. Increasing the amount of nitrogen fertilizer can promote the transport of dry matter to grain and improve dry matter transport efficiency after anthesis. Under the treatment of medium and high nitrogen fertilizer, maize was easy to obtain a higher yield, but excessive nitrogen fertilizer inhibited the increase of yield. This study provides theoretical and practical guidance for maize production techniques.

Effects of Crown Thinning on Baldcypress Height, Diameter, and Volume Growth

1988 ◽  
Vol 12 (4) ◽  
pp. 252-256 ◽  
Author(s):  
Stephen G. Dicke ◽  
John R. Toliver
Keyword(s):  
Volume Growth ◽  
Basal Area ◽  
Height Growth ◽  
Taxodium Distichum ◽  
Volume Increment ◽  
Crown Thinning ◽  
Epicormic Branching

Abstract Crown thinning a 63-year-old stand of baldcypress (Taxodium distichum [L.] Rich.) averaging 220 ft²/ac of basal area to 180, 140, and 100 ft²/ac resulted in 5-year diameter growths of 0.44, 0.51, and 0.77 in., respectively. The unthinned control was significantly less at 0.31 in. Six-year height growth averaged 3.1 ft and was not influenced by treatment. Thinning to 140 and 100 ft²/ac stimulated epicormic branching on many trees, which may lower log quality. All crown thinning treatments appeared to increase sawtimber volume increment and sawtimber volume/ac over the control 5 years after thinning. South. J. Appl. For. 12(4):252-256.

scholarly journals The Difficulty of Predicting Eastern Spruce Dwarf Mistletoe in Lowland Black Spruce: Model Benchmarking in Northern Minnesota, USA

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 843
Author(s):  
Ella R. Gray ◽  
Matthew B. Russell ◽  
Marcella A. Windmuller-Campione
Keyword(s):  
Stand Structure ◽  
Black Spruce ◽  
Forest Health ◽  
Basal Area ◽  
Predictive Performance ◽  
Stand Age ◽  
Management Decisions ◽  
Dwarf Mistletoe ◽  
Growing Seasons ◽  
Model Interpretation

Insects, fungi, and diseases play an important role in forest stand development and subsequently, forest management decisions and treatments. As these disturbance agents commonly occur within and across landscapes, modeling has often been used to inform forest planning and management decisions. However, models are rarely benchmarked, leaving questions about their utility. Here, we assessed the predictive performance of a Bayesian hierarchical model through on–the-ground sampling to explore what features of stand structure or composition may be important factors related to eastern spruce dwarf mistletoe (Arceuthobium pusillum Peck) presence in lowland black spruce (Picea mariana (Mill.) B. S. P.). Twenty-five state-owned stands included in the predictive model were sampled during the 2019 and 2020 growing seasons. Within each stand, data related to the presence of eastern spruce dwarf mistletoe, stand structure, and species composition were collected. The model accurately predicted eastern spruce dwarf mistletoe occurrence for 13 of the 25 stands. The amount of living and dead black spruce basal area differed significantly based on model prediction and observed infestation, but trees per hectare, total living basal area, diameter at breast height, stand age, and species richness were not significantly different. Our results highlight the benefits of model benchmarking to improve model interpretation as well as to inform our understanding of forest health problems across diverse stand conditions.

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