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Silva Fennica 1926-1997
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Acta Forestalia Fennica
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Articles containing the keyword 'logs'.

Category: Research article

article id 1054, category Research article
Karin Kolis, Juhana Hiironen, Esa Ärölä, Arvo Vitikainen. (2014). Effects of sale-specific factors on stumpage prices in Finland. Silva Fennica vol. 48 no. 3 article id 1054. https://doi.org/10.14214/sf.1054
Highlights: Data on 4824 individual sales were used to estimate which factors affect stumpage prices; The time of sale, seasonal harvest restrictions, the location and the assortment affected prices; Larger total volumes and shorter forest haulage distances raised unit prices; A higher percentage of the assortment and percentage of sawlogs within the sale corresponded to higher prices.
Buyers of standing timber take not only the market situation but also the harvest costs into consideration when making purchase offers. In Finland, 85% of all timber is sold as standing timber, but there is little information for forest owners and third parties regarding how differences in harvest costs are reflected in the stumpage prices. This article analyses the relationship between sale-specific factors and stumpage prices in Finland. Data on 4824 standing timber sales between 2008 and 2012 were gathered from five local Forest Management Associations. Regression analyses were run on the stumpage prices (euros m–3) paid for sawlogs and pulpwood. Seasonal harvest restrictions, the volume of the sale and the timber assortment influenced stumpage prices, as did the presence of forest damages. Prices also differed over time and between locations. Furthermore, the forest haulage distance was statistically significant for pulpwood. The results suggest that the size of the individual sales and the composition of assortments affect the income owners earn from their forest. The results can be used to estimate stumpage prices and the monetary impacts on forest owners of procedures such as forest road network planning and land consolidation, as well as for valuation of forests.
  • Kolis, Aalto University, Department of Real Estate, Planning and Geoinformatics, P.O. Box 12200, FI-00076 Aalto, Finland ORCID ID:E-mail: karin.kolis@aalto.fi (email)
  • Hiironen, Aalto University, Department of Real Estate, Planning and Geoinformatics, P.O. Box 12200, FI-00076 Aalto, Finland ORCID ID:E-mail: juhana.hiironen@aalto.fi
  • Ärölä, National Land Survey of Finland, Production Support Services, P.O. Box 84, FI-00521 Helsinki, Finland ORCID ID:E-mail: esa.arola@nls.fi
  • Vitikainen, Aalto University, Department of Real Estate, Planning and Geoinformatics, P.O. Box 12200, FI-00076 Aalto, Finland ORCID ID:E-mail: arvo.vitikainen@aalto.fi
article id 86, category Research article
Mats Jonsell, Jesper Hansson. (2011). Logs and stumps in clearcuts support similar saproxylic beetle diversity: implications for bioenergy harvest. Silva Fennica vol. 45 no. 5 article id 86. https://doi.org/10.14214/sf.86
Stumps from clear cuts are increasingly used for bioenergy. Extracting this wood will reduce the habitat available for saproxylic (wood-living) organisms. As little is known about the species assemblages that will be affected, we investigated the diversity of saproxylic beetles in stumps on clear-felled sites and as a reference, we compared it with the diversity in downed logs. Stumps and logs of aspen (Populus tremula L.), birch (Betula pubescens Ehrh. and B. verrucosa Ehrh.[syn. B. pendula Roth]), spruce (Picea abies (L.) Karst.) and pine (Pinus sylvestris L.) were examined in clear cuts of two different ages: one summer old and 4–5 years old. The beetles were sampled by sieving bark (0.25 m2) peeled from the wood. The samples were taken in pairs of one log and one stump situated close together and of the same tree species, age since death and diameter. In total 3348 saproxylic beetles belonging to 124 species were found in 176 samples. The stumps had a similar number of species to the logs both as measured per sample and as an accumulated number. Exceptions were 4–5 years old wood of birch and pine where the number was significantly higher in the stumps. The number of red-listed species was also similar between stumps and logs. Species composition was more different between the stumps and logs of conifers than of deciduous trees. We conclude that clear-felled stumps have a diverse saproxylic insect fauna. This has to be taken into account if large scale extraction of logging stumps is implemented.
  • Jonsell, Swedish University of Agrarian Sciences, Dept of Ecology, Uppsala, Sweden ORCID ID:E-mail: mats.jonsell@ekol.slu.se (email)
  • Hansson, Swedish University of Agrarian Sciences, Dept of Ecology, Uppsala, Sweden ORCID ID:E-mail:
article id 117, category Research article
Harri Kilpeläinen, Jari Lindblad, Henrik Heräjärvi, Erkki Verkasalo. (2011). Saw log recovery and stem quality of birch from thinnings in southern Finland. Silva Fennica vol. 45 no. 2 article id 117. https://doi.org/10.14214/sf.117
The objective of this study was to examine the timber quality of silver birch (Betula pendula Roth) and European white birch (Betula pubescens Ehrh.) trees in the first and second thinnings in southern parts of Finland, from the viewpoint of sawing of small-diameter, short logs, in particular. The average stem volume of birch was 0.140 m3 in the first thinning stands and 0.206 m3 in the second thinning stands. In planted stands, the trees were larger in the first thinnings but slightly smaller in the second thinnings, compared with naturally regenerated pure birch stands or mixed stands of Norway spruce and birch species. Almost 60% of the harvested and 35% of the remaining stems that could provide saw logs were graded as pulpwood for timber quality due to the occurrence of stem defects. The most common stem defects were multiple crooks and middle crooks. Only minor between-stratum differences were detected in the numbers of defects. Depending on the bucking option, the total percentage of saw and plywood logs from the total birch recovery in the thinning of the sample stands varied between 11.7 and 18.2. The recovery of saw logs was clearly higher in the second thinnings, 12–19%, than in the first thinnings, 8–14%. Of the stand types, saw log recovery was the highest in planted birch stands, 12–19%, but lower in naturally regenerated pure birch stands and mixed stands of Norway spruce and birch. The highest share of saw logs was in the second thinning of planted stands, 17–25%. This study shows that the harvesting recoveries of end-use based timber assortments can be estimated in different kinds of thinning birch stands. Based on tree and log dimensions and stem squality, silver birch firstly from plantations and secondly from mixed stands should be the most interesting source of raw material for the saw milling, furniture and interior product sectors.
  • Kilpeläinen, Finnish Forest Research Institute, Eastern Finland Research Unit, P.O. Box 68, FI-80101 Joensuu, Finland ORCID ID:E-mail:
  • Lindblad, Finnish Forest Research Institute, Eastern Finland Research Unit, P.O. Box 68, FI-80101 Joensuu, Finland ORCID ID:E-mail:
  • Heräjärvi, Finnish Forest Research Institute, Eastern Finland Research Unit, P.O. Box 68, FI-80101 Joensuu, Finland ORCID ID:E-mail: henrik.herajarvi@metla.fi (email)
  • Verkasalo, Finnish Forest Research Institute, Eastern Finland Research Unit, P.O. Box 68, FI-80101 Joensuu, Finland ORCID ID:E-mail:

Category: Research note

article id 148, category Research note
Ola Lindroos, Magnus Matisons, Petter Johansson, Tomas Nordfjell. (2010). Productivity of a prototype truck-mounted logging residue bundler and a road-side bundling system. Silva Fennica vol. 44 no. 3 article id 148. https://doi.org/10.14214/sf.148
When recovering logging residues (LR) for bioenergy its density should be increased before road transport, otherwise a low proportion of the trucks’ load capacity will be used. One way this can be currently done is to compress LR into bundles that are forwarded to roadside landing. A less well-developed alternative is to forward loose LR and bundle it at landing. In the presented study, a prototype specifically developed for road-side bundling was found to produce larger, heavier bundles than bundling machinery intended for in-field use (mean length, diameter and raw bulk density 4.7 m, 0.8 m and 285 kg m–3, respectively, with 299–445 kg oven dry matter per bundle). The machine was also at least 30% more productive than previously described in-field bundling systems, producing 14–19 bundles per productive work hour (PWh), equivalent to 5.2–7.8 oven-dry tonnes PWh–1. Bundles were estimated to use 67–86% of an LR truck’s 30 tonnes load capacity, similar to proportions used when transporting loose LR. However, a continuous feeding and compressing process would probably almost double productivity, while longer bundles would enable full use of truck load capacity. With such improvements bundling at road-side could provide a viable alternative to current LR-recovering systems.
  • Lindroos, Department of Forest Resource Management, Swedish University of Agricultural Sciences, Umeå, Sweden ORCID ID:E-mail: ola.lindroos@srh.slu.se (email)
  • Matisons, Department of Forest Resource Management, Swedish University of Agricultural Sciences, Umeå, Sweden ORCID ID:E-mail:
  • Johansson, Sveaskog Förvaltnings AB, Vindeln, Sweden ORCID ID:E-mail:
  • Nordfjell, Department of Forest Resource Management, Swedish University of Agricultural Sciences, Umeå, Sweden ORCID ID:E-mail:

Category: Article

article id 7167, category Article
Veijo Heiskanen. (1966). Tutkimuksia rauduskoivikon karsimisen kannattavuudesta. Acta Forestalia Fennica vol. 81 no. 2 article id 7167. https://doi.org/10.14214/aff.7167
English title: Studies on the profitability of pruning of common birch (Betula pendula) stands.

The objective of the present investigation was to clarify the profitability of pruning silver birch (Betula verrucosa, now Betula pendula Roth) in the growing of raw material for veneer industry. Calculations were made on the grade, value, and price of pruned and untreated butt logs as well as on costs of pruning and the development of pruned trees.

The grade distribution of unpruned veneer butt logs, the grade distribution of the veneer yield, and consequently, the value of veneer yield and log prices at the plant are considerably better than those of average logs. The grade, value and price increased with increasing diameter. The value and price of pruned butt logs depended primarily on the difference between the turning pruning diameters, and their increase with decreasing pruning diameter and increasing turning diameter. The value of pruned butt logs is always considerably higher than that of unpruned logs. The increase in the value correlates to the pruning and turning diameters, and is, for example, in rotary-cut logs which have been pruned when 10 cm in diameter 80–130%.

Pruning increases the stumpage in naturally regenerated silver birch stands on Oxalis-Myrtillus site by 2,000–3,000 Fmk/ha when employed at 20 years of stand age and rotary cutting at 60–80 years of age respectively. The average pruning costs on Oxalis-Myrtillus site are 51–57 Fmk/ha.

The PDF includes a summary English.

  • Heiskanen, ORCID ID:E-mail:
article id 7372, category Article
Vilho Seppänen. (1942). Sahatukkien teosta aikatutkimuksen valossa. Acta Forestalia Fennica vol. 50 no. 19 article id 7372. https://doi.org/10.14214/aff.7372
English title: Time studies on making of saw logs.

A time study was conducted in saw log harvesting site in state forests of Evo in Southern Finland in 1934. Felling was performed in teams of two loggers. Two teams were observed. The work was divided into several stages of work: felling, branching, cross-cutting, barking and making of top log. On the site grew Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.).

The daily working hours not including breaks was in average 5 hours and 33 minutes. The most time-consuming stage of the work was barking of the stem (55% of working time for Scots pine and 47% for Norway spruce), followed by felling (22.5% for pine and 19.4% for spruce), branching (11.7% and 21.6%) and cross-cutting (11.3% and 11.8%). Temperature affects barking strongly. Scots pine is slower to bark than Norway spruce. Similarly, butt and middle logs are slower to bark than top logs. It took in average 79.02 min to process one solid m3 of timber with bark and 91.45 min without bark.

The PDF includes a summary in German.

  • Seppänen, ORCID ID:E-mail:
article id 7371, category Article
Einari Wuoti. (1942). Kuusisahapuun teknillisen ja pinokuution välinen suhde sekä sen riippuvaisuus muotoluokasta. Acta Forestalia Fennica vol. 50 no. 18 article id 7371. https://doi.org/10.14214/aff.7371
English title: Relation between technical and piled cubic meter of Norway spruce saw logs and their relation to form class.

Due to shortage of large logs, sawmill industry has been forced to buy also smaller logs, which also pulp industry uses as a raw material. Sawmills must be careful in the pricing of the logs, because profitability of sawing of timber depends on the size of the logs. These industries use different measures when they buy timber: pulp industry uses piled measure in meters, while saw logs are measured individually in cubic feet. The aim of the study was to develop sets of figures on technical cubic measure of a saw log and its relation to a piled cubic meter from the same log used as pulp wood. In addition, the effect of form class on the measures was studied.

The relation was assessed for trunks that had good, mediocre or unfavourable form class, which distinction is easy to make for a forest worker buying timber. The relations can be used by a buyer of saw logs or pulpwood who need to compare the prices or when the seller of the wood compares the offers.

The PDF includes a summary in German.

  • Wuoti, ORCID ID:E-mail:
article id 5261, category Article
Matti Kärkkäinen. (1986). Koivuvaneritukkien ja -runkojen arvosuhteet. Silva Fennica vol. 20 no. 1 article id 5261. https://doi.org/10.14214/sf.a15440
English title: Value relations of birch veneer logs and stems in Finland.

A model was developed in order to describe the peeling of veneer for determining value relationship for birch veneer logs and stems. The model was based on selling prices of veneer and other products as well as processing costs. The model was utilized for determining the effect of various input variables on the log value.

According to the results, the effect of tree size was important for the value of raw material. Even knottiness had an effect although only in the higher manufacturing costs of knotty veneer were taken into account. Pruning was a method to increase substantially the proportion of knotless veneer.

The PDF includes an abstract in English.

  • Kärkkäinen, ORCID ID:E-mail:
article id 5251, category Article
Markku Halinen. (1985). Männyn nuoruusvaiheen kasvunopeuden vaikutus sahatavaran laatuun. Silva Fennica vol. 19 no. 4 article id 5251. https://doi.org/10.14214/sf.a15430
English title: The effect of the growth rate of young Scots pine on the quality of sawn goods.

Totally 653 battens and planks sawn from butt logsof Scots pine (Pinus sylvestris L.) were chosen from 3 saw mills. The sawn goods were sorted according to normal sorting principles. In order to determine growth rate in the youth, the mean value of the average ring width was measured at the butt end at various distances from the pith.

The average ring width increased as the quality of the sawn goods decreased. The difference between the quality classes in ring width was measured between 2 and 4 cm from the pith. As the size of sawn goods, and, simultaneously, the log size increased, the average ring width increased in a given quality class. Research reinforced previous results, in which slow diameter growth of young Scots pines has been shown to reflect the good quality of sawn goods.

The PDF includes a summary in English.

  • Halinen, ORCID ID:E-mail:
article id 5246, category Article
Matti Kärkkäinen, Markku Halinen. (1985). Mäntysahatukkien minimivaatimusten täsmentäminen. Silva Fennica vol. 19 no. 3 article id 5246. https://doi.org/10.14214/sf.a15425
English title: Reappraisal of minimum requirements of Scots pine saw logs.

A test sawing was made of 807 Scots pine (Pinus sylvestris L.) saw logs of varying size and quality. The most important knot characteristic affecting the value of sawn goods was the diameter of the thickest dry knot. The new minimum requirements for pine logs were proposed on the basis of top diameter of the log and the diameter of the thickest dry and living knot.

The PDF includes a summary in English

  • Kärkkäinen, ORCID ID:E-mail:
  • Halinen, ORCID ID:E-mail:
article id 5182, category Article
Matti Kärkkäinen, Herman Hakala. (1983). Kuusitukin koon vaikutus sivulautojen taivutus- ja puristuslujuuteen. Silva Fennica vol. 17 no. 2 article id 5182. https://doi.org/10.14214/sf.a15098
English title: Effect of log size on the bending and compression strength of side boards in Norway spruce.

In order to evaluate the strength properties of boards made from small and large Norway spruce (Picea abies) butt logs, 15 small (top end diameter 13 cm) and 15 large (top end diameter 25 cm) logs were sampled from a sawmill in Finland. From each log two test pieces were made in order to measure the bending and compression strength, dry density and average ring width.

The boards from small logs were stronger and their density higher. When the differences between groups were analysed it was found that the strength was determined by the density and ring width. When the density was kept constant, the increase in ring width had a decreasing effect on the strength properties. Because there was a negative correlation between ring width and density, ring width alone had a great effect on the strength properties.

The PDF includes a summary in English.

  • Kärkkäinen, ORCID ID:E-mail:
  • Hakala, ORCID ID:E-mail:
article id 5083, category Article
Matti Kärkkäinen. (1980). Havaintoja koivutukkien epäpyöreydestä ja pituusmittaeroista. Silva Fennica vol. 14 no. 3 article id 5083. https://doi.org/10.14214/sf.a15024
English title: Observations on the out-of-roundness and deviations from nominal lengths of birch logs.
English keywords: Betula; birch; logs; roundness; diameter

A material of 478 birch logs were measured. The horizontal diameter was on average larger than the vertical one, the difference increasing with the increasing diameter. The reason was supposed to be the effect of sweep and out-of-roundness of logs. The difference between the actual and nominal length increased with the increasing lengths, but decreased with increasing diameter.

The PDF includes a summary in English.

  • Kärkkäinen, ORCID ID:E-mail:
article id 5004, category Article
Matti Kärkkäinen. (1978). Haapatukkien lahoisuus. Silva Fennica vol. 12 no. 3 article id 5004. https://doi.org/10.14214/sf.a14858
English title: Occurrence of decay in aspen logs.
Original keywords: haapa; tukki; laho; tyvitukit
English keywords: aspen; Populus tremula; logs; decay; butt logs

At three Finnish match factories 1,629 aspen logs were measured (see Kärkkäinen and Salmi 1978). When the estimation was based on the condition of the butt cross section of a log, less than half of the logs were sound without any discoloration or decay. Based on the condition of the top cross-section, the corresponding figure was a little higher than 50%. The logs with decay were bigger than those without it. There were relatively more butt logs among the logs with decay than among the totally sound logs.

The PDF includes a summary in Finnish.

  • Kärkkäinen, ORCID ID:E-mail:
article id 5004, category Article
Matti Kärkkäinen. (1978). Haapatukkien lahoisuus. Silva Fennica vol. 12 no. 3 article id 5004. https://doi.org/10.14214/sf.a14858
English title: Occurrence of decay in aspen logs.
Original keywords: haapa; tukki; laho; tyvitukit
English keywords: aspen; Populus tremula; logs; decay; butt logs

At three Finnish match factories 1,629 aspen logs were measured (see Kärkkäinen and Salmi 1978). When the estimation was based on the condition of the butt cross section of a log, less than half of the logs were sound without any discoloration or decay. Based on the condition of the top cross-section, the corresponding figure was a little higher than 50%. The logs with decay were bigger than those without it. There were relatively more butt logs among the logs with decay than among the totally sound logs.

The PDF includes a summary in Finnish.

  • Kärkkäinen, ORCID ID:E-mail:
article id 4950, category Article
Matti Kärkkäinen. (1976). Lisähavaintoja haapatukkien poikkipinta-alan mittaamisesta. Silva Fennica vol. 10 no. 4 article id 4950. https://doi.org/10.14214/sf.a14796
English title: Auxiliary observations on the measurement of the cross-sectional area of aspen logs.

In this study the area, 8 diameters, and 16 radii were measured of 174 discs representing aspen logs in a mill. The average difference between the largest and smallest diameter was 18 mm, or 7% of the longest diameter. The difference between the largest and smallest radius was 29 mm, or 22% of the longest radius. The diameter was on the average 2.4 mm longer than the two corresponding radii.

The exact area of each disc was measured using a planimeter. In comparison, the area based on the circle formula the diameter being the arithmetic mean of largest and smallest diameters overestimated the area by 1.7%. The results also indicated that the use of random direction in the measurement of diameter overestimated the cross-sectional area on the average by 1.8%.

The study is continuation of the earlier study where the bibliography is presented. As far as the results are comparable, they support each other.

The PDF includes a summary in English.

  • Kärkkäinen, ORCID ID:E-mail:
article id 4925, category Article
Matti Kärkkäinen. (1975). Pohjoissuomalaisten mäntytukkien soikeus. Silva Fennica vol. 9 no. 4 article id 4925. https://doi.org/10.14214/sf.a14767
English title: Ovalness of Scots pine logs in Northern Finland.

The material of this study consists of 1,080 Scots pine (Pinus sylvestris L.) saw logs measures in two saw mills in Northern Finland. The largest and the smallest top-diameter of each log was measured under bark. According to the results, the ovalness was rather small, 1 mm or 4.9% on average. On the other hand, only 14.3% of all logs showed a diameter difference smaller than 2%. The ovalness was larger than 10% in 5.8% of all logs.

The PDF includes a summary in English.

  • Kärkkäinen, ORCID ID:E-mail:
article id 4922, category Article
Matti Kärkkäinen. (1975). Koivu- ja haapatukkien poikkipinta-alan mittaaminen. Silva Fennica vol. 9 no. 3 article id 4922. https://doi.org/10.14214/sf.a14764
English title: Measurement of the cross-sectional area of birch and aspen logs.

The aim of the study was to determine the extent to which the cross section of birch (Betula sp.) and aspen (Populus tremula L.) logs differ from a circle and to test some simple methods for measuring the cross-sectional area which can be used, for instance, for determining the volume of the logs. The material consisted of 420 debarked birch disks and 240 aspen disks which were representative of the logs arriving at two factories.

The convex deficit values for the material were very small, the cross-sectional area error being in general less than 1%. On the other hand, the other parameters deviated from the circular form to quite a large degree. It was also evident that the radii measured from the piths to the surface of the wood varied considerably more in the same disk, as regards length, than the diameters measured in different directions.

It was evident that the shape of the average cross-sectional area was not in general elliptical. It thus appears that any method for measuring the cross-sectional area which is based on elliptical formula is not suitable. The method which gave the best result was that in which the cross-sectional area was taken as the average of the area of the circle calculated from the smallest diameter and that calculated from the diameter passing at right angles to it. This method also appeared to be the best for disks which deviated to quite a large degree from the circular form. The suitability of this method is increased by the fact that the relative error is only slightly dependent on the size of the disk.

The PDF includes a summary in English.

  • Kärkkäinen, ORCID ID:E-mail:
article id 4896, category Article
Matti Kärkkäinen. (1974). Keskusmuotoluvun perusteita tukkien ja kuitupuun mittauksessa. Silva Fennica vol. 8 no. 1 article id 4896. https://doi.org/10.14214/sf.a14740
English title: Foundations of middle form factor in the measurement of logs and pulpwood.

In this literature review some error possibilities in the measurement of solid volume of logs and pulpwood are discussed. Although both underestimation and overestimation can occur for various reasons it seems likely that in the stereometric measurement method the real volume is underestimated, at least when Huber’s formula is applied, and the respective middle form factors are too low. Numerous results of empirical investigations are presented in the paper, too.

The PDF includes a summary in English.

  • Kärkkäinen, ORCID ID:E-mail:
article id 4768, category Article
Veijo Heiskanen. (1968). Havaintoja eräiden vikaisuuksien vaikutuksesta mäntytukkien sahauksessa. Silva Fennica vol. 2 no. 3 article id 4768. https://doi.org/10.14214/sf.a14553
English title: Influence of some log defects in sawing of pine logs.

The present paper presents studies on the influence of some relatively common defects of Scots pine logs in Northern Finland on both the sawing yield and on the quality of the sawn goods. The study was based on test sawing of 25 logs for each of the defects (upright limb, heart shake and various kinds of wounds and scars) at Karihaara sawmill. The yield was graded into grades used for export timber according to the system of the sawmill. The proportion of the different export grades (U/S), fifths, sixths and culls) were used as characteristics together with the ratio of raw-wood consumption expressed as cu.ft/std.

Upright limbs occurring in a piece of sawn timber was shown to lower its quality to fifth grade in 43.5%, to sixth grade in 46.8% and to the category of culls in 6.5% of all cases. Only 3.2% of the cases the piece remained in U/S-grades. The size of the upright limb was the most important factor lowering the quality and affecting the ratio of raw-wood consumption.

Heart shakes are relatively common defects in pine logs deriving from over-mature trees. The quality-decreasing influence on the sawing yield depends clearly on the length of the shake in the cross-section. The same characteristics also decreases the ratio of raw-wood consumption. In addition, twisting and star shakes are considerably more harmful than straight ones. If rot occurs in connection with shakes, the places marred by the shakes are only capable of yielding sixth-grade sawn goods or culls.

Scar encountered in logs affect the sawn yield and its quality to quite a varying degree, but these defects themselves may also vary considerably both in size and quality. The length of the scar is highly significant as a quality-decreasing factor. If, in addition, rot is encountered, the defect is of a severe nature.

The PDF includes a summary in English.

  • Heiskanen, ORCID ID:E-mail:
article id 4760, category Article
Veijo Heiskanen. (1968). Kuusitukkien laatuluokkajakautuma Etelä-Suomessa. Silva Fennica vol. 2 no. 1 article id 4760. https://doi.org/10.14214/sf.a14544
English title: Grade distribution of Norway spruce logs in Southern Finland.

The aim of the present study was to find the factors influencing the distribution of Norway spruce (Picea abies (L.) H. Karst.) logs on various grades with special stress on the effects of the grade on the value of logs. The material was obtained from ten sawmills located in Southern Finland by grading a total of 13,559 logs.

The results showed that knottiness in its different forms of appearance is the most important factor influencing the quality of spruce logs. Its significance is clearly greater in spruce than in Scots pine saw logs. Among the other defects, the most common are crooks. Even scars and decay occur to a considerable degree, but other defects seldom affect the grade. The quality of butt logs is markedly better than that of top logs. Both in butt and top logs the smallest logs in diameter are of poorer quality. However, in the largest diameter classes the quality begins again to decrease.

The difference in the quality of logs of the same grade at various sawmills is very small. The results of grading at varying times at the same sawmill show greater differences than can be observed between different sawmills. However, the logs of sawmills that procure the timber from coastal areas and islands are inferior to those which procure the timber from the mainland.

The PDF includes a summary in English.

  • Heiskanen, ORCID ID:E-mail:
article id 7186, category Article
Bror-Anton Granvik. (1968). Sahaustuloksen määrä ja laatu havutukkien kenttäpyörösahauksessa. Acta Forestalia Fennica no. 86 article id 7186. https://doi.org/10.14214/aff.7186
English title: The quantity and quality of the sawing yield in sawing coniferous logs with circular saw.

The aim of the study was to find out the ratio of raw wood consumption and the quantity and quality of the sawing yield using circular saws. The unit of study was one single log, the Norway spruce logs were divided into two grades and Scots pine logs in three grades. The principal material of the study was collected in 1950-51 using four types of saws of type EKA-50. The data consisted of 1,690 logs.

On the basis of the material, the efficiency of centre-piece sawing was 63.9% of the technical volume. On the average, 32.1% was unsorted goods, 11.5% fifths, 19.1% sixths and 1.2% culls. For spruce, the efficiency was superior to pine, which means that the consumption of raw wood for preparation of one standard of sawn goods is smaller in spruce than in pine. The volume of side boards trimmed reached about 2% of the total log volume. The efficiency of sawing and the ratio of raw-wood consumption were calculated both on the basis of the estimated and actual volume of trimmed goods. The raw-wood consumption is particularly good in logs of small and large top-diameter.

Goods sawn with circular saw have a characteristic shape. They are thinner at the ends than in the middle parts, and the deviation from the correct measure is larger in the first than in the last end of the pieces. They are also wedge-shaped because of the first piece sawn is thinner than the second one. The deviation from the correct measure exceeded the allowance for shrinking in seasoning. The goods are often under sized even if surplus measure occurs. In goods sawn using frame saws, however, it was difficult to discover any deviation from the correct measure.

The PDF includes a summary in English.

  • Granvik, ORCID ID:E-mail:
article id 4646, category Article
Paavo Yli-Vakkuri. (1955). Tutkimuksia metsänhoitolautakuntien ja -yhdistysten leimaustoiminnan kehityksestä. Silva Fennica no. 87 article id 4646. https://doi.org/10.14214/sf.a9108
English title: Studies on crop marking of District Forestry Boards and Forest Management Associations.

Wood demand and practices in the marking of trees for cutting have affected the silvicultural state of the forests of Finland in the early 1900s. The aim of the study was to study the development of timber sales and the marking of trees for logging, with a special emphasis on variation in the volume of the sales and assortment range. The study is based on statistics of the District Forestry Boards and Forest Management Associations about timber marked for cutting in 1931-1953.

The professionals in the District Forestry Boards and Forest Management Associations have marked annually in average 9 million stems of heavy timber and about 7 million m3 of stacked wood for sales. The volume  follows business cycles, the changes in the volume of stacked wood being larger than of heavy timber. When demand was high, the number of professional workers limited the supply of wood. There were large differences in the volumes marked within the country. The share of small diameter stacked wood has increased since 1930s compared to heavy timber.

The article includes a summary in German.

  • Yli-Vakkuri, ORCID ID:E-mail:
article id 4642, category Article
Einar Maliniemi. (1954). Tilastollinen tutkimus sahapuiden hakkuusta ja ajosta Perä-Pohjolassa. Silva Fennica no. 82 article id 4642. https://doi.org/10.14214/sf.a9103
English title: Statistical analysis on felling and haulage of sawlogs in Perä-Pohjola in Northern Finland.

The wages of logging and haulage has been dependent on the decisions of foremen. The aim of this study was to provide better insight on how working conditions in a logging site affect productivity of the work. Six working sites operated by Forest Service, Veitsiluoto Oy and Kemi Oy in the communes of Salla, Muonio and Kolari in Lapland were studied. The forests in the area were mostly Scots pine (Pinus sylvestris L.).

The effect of average volume of the stems, the average daily haulage over distances of various lengths, density of the stand and shape of the stem on effectivity was calculated. The size of the team was of considerable importance to the felling and haulage result in the Northern Finland where the feller assists in loading of the logs. One of the aims of the study was to find out what size of team is most advantageous for each haulage distance. The results show the optimum distance of haulage for teams of different sizes.

The article includes a summary in English.

  • Maliniemi, ORCID ID:E-mail:
article id 4613, category Article
Veijo Heiskanen. (1951). Mäntysahatukkien laatuarvioinnin tarkkuudesta. Silva Fennica no. 69 article id 4613. https://doi.org/10.14214/sf.a14009
English title: Accuracy of quality grading of Scots pine saw logs.

Silva Fennica Issue 69 includes presentations held in 1948-1950 in the fourth professional development courses, arranged for foresters working in the Forest Service. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.

This presentation discusses accuracy of the quality grading of Scots pine (Pinus sylvestris L.) saw logs suggested by professor Ilmari Vuoristo based on a data collected by Valtiala. According to the study, greatest inaccuracies in the grading by visual inspection was caused by differences between the evaluators.

  • Heiskanen, ORCID ID:E-mail:
article id 4612, category Article
Veijo Heiskanen. (1951). Mäntysahatukkien laadun mukaisista arvosuhteista. Silva Fennica no. 69 article id 4612. https://doi.org/10.14214/sf.a14008
English title: Value grading of Scots pine saw logs.

Silva Fennica Issue 69 includes presentations held in 1948-1950 in the fourth professional development courses, arranged for foresters working in the Forest Service. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.

Quality grading has been rarely used in pricing of saw logs due to lack of knowledge on how the quality of logs affects the value of the sawn wood. This presentation discusses the subject based on unpublished data professor Ilmari Vuoristo collected in 1930s on effects of timber grading on the quality and value of sawn wood. The quality classification developed by professor Vuoristo is presented.

  • Heiskanen, ORCID ID:E-mail:
article id 4611, category Article
Veijo Heiskanen. (1951). Sahatukkien laatuluokittelulla saavutettavista eduista. Silva Fennica no. 69 article id 4611. https://doi.org/10.14214/sf.a14007
English title: Benefits of qualitative classification of saw logs.

Silva Fennica Issue 69 includes presentations held in 1948-1950 in the fourth professional development courses, arranged for foresters working in the Forest Service. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.

This presentation describes benefits of the qualitative classification of saw logs to forest owners and forest industry.

  • Heiskanen, ORCID ID:E-mail:
article id 4610, category Article
Veijo Heiskanen. (1951). Sahatukkien laatuluokittelutavat. Silva Fennica no. 69 article id 4610. https://doi.org/10.14214/sf.a14006
English title: Methods of saw log classification according to quality.

Silva Fennica Issue 69 includes presentations held in 1948-1950 in the fourth professional development courses, arranged for foresters working in the Forest Service. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.

This presentation describes the uses and principles of different kinds of grading of saw logs.

  • Heiskanen, ORCID ID:E-mail:
article id 4609, category Article
F. E. Siimes. (1951). Sahatukkien laatuluokittelu sahatavarain käytön, lajittelun ja koesahausten valossa. Silva Fennica no. 69 article id 4609. https://doi.org/10.14214/sf.a14005
English title: Classification according to quality of saw logs in the light of use, grading and sawing tests of sawn timber.

Silva Fennica Issue 69 includes presentations held in 1948-1950 in the fourth professional development courses, arranged for foresters working in the Forest Service. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.

This presentation describes the grading of sawn timber for export and domestic use, and suggests improvements to grading of the sawn products in the saw mills to better answer the needs of export.

  • Siimes, ORCID ID:E-mail:
article id 4565, category Article
Paavo Jokinen. (1939). Asutustoiminnan yhteydessä valtiolle pidätettävät arvopuut ja niiden hakkaaminen. Silva Fennica no. 52 article id 4565. https://doi.org/10.14214/sf.a13972
English title: Reservation of valuable timber-trees in connection to settlement activities.

Silva Fennica issue 52 includes presentations held in professional development courses, arranged for foresters working in public administration in 1938. The presentations focus on practical issues in forest management and administration, especially in regional level. The education was arranged by Forest Service.

This presentation describes the conditions according to which the state can reclaim valuable timber-trees on forest land which ownership is transferred to landless population in settlement work.

  • Jokinen, ORCID ID:E-mail:
article id 4460, category Article
I. Lassila. (1931). Suunnitelma Suomen lauttausväylillä uitetun puun uppoamisen tutkimisesta. Silva Fennica no. 19 article id 4460. https://doi.org/10.14214/sf.a9001
English title: Research proposal for studies on sinking of logs in the floating channels of Finland.

Majority of the timber floated in Finland has been floated loose. Repair of the floating channels in the end of 1800s decreased the amount of sunken logs and loss of timber during the transportation. The increase of floating of pulpwood and other small timber has later increased the number of sunken logs. More information is needed on the amount and quality of floated timber, also the floating channels should be classified. A detailed study plan to investigate how big proportion of the timber is lost during floating, which factors influence the sinking of timber, and how the timber dries in the forest depots is presented. A classification of timber by its floatability is presented.

The PDF includes a summary in German.

  • Lassila, ORCID ID:E-mail:

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