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Silva Fennica 1926-1997
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Acta Forestalia Fennica
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Articles by Yrjö Roitto

Category: Article

article id 7137, category Article
Yrjö Roitto. (1963). Ison-Saimaan yhteisuitto-ongelma. Acta Forestalia Fennica vol. 75 no. 3 article id 7137. https://doi.org/10.14214/aff.7137
English title: Problem of co-operative floating on the Iso-Saimaa in Eastern Finland.

In Finland roundwood is floated either privately or co-operatively. In the later, a co-operative floating association is established to operate floating. The association is compulsory association of those enterprises who want to have wood floated along the floating routes of the area. It is favoured when the number of enterprises and the wood to be floated is large. In addition, costs are lower than in private floating.

Floating in Lake Saimaa area in Central Finland can be divided into Iso-Saimaa, where floating is private, and into Saimaa Water System, where floating is operated by a co-operative floating association. It has been suggested that adoption of co-operative floating in Iso-Saimaa would be to the common interest. This study aimed at finding out if co-operative floating influences the transport costs, and if co-operative floating increases competition of roundwood by forest industry companies.

According to the study, the costs of most enterprises would decrease. The total decrease in costs would amount to 65 million Finnish marks annually, about 20% less than the present costs. The change of organization would not alter the competitive relationship in buying roundwood. On the other hand, it would seem that co-operative floating would be less flexible than private floating. The management of a large organization, whose effective operation time would cover only a part of the year, would meet with some difficulties. Also, co-operative floating would reduce competition among enterprises.

The PDF includes a summary in English.

  • Roitto, ORCID ID:E-mail:
article id 7477, category Article
Yrjö Roitto. (1958). Raakapuun kaukokuljetus Saimaan vesistössä. Acta Forestalia Fennica vol. 67 no. 3 article id 7477. https://doi.org/10.14214/aff.7477
English title: Transportation of round timber in the Lake Saimaa water system.

This paper aims at investigating which factors, in the point of view of the entrepreneur, define the choice of long-distance transport either as floating in bundles, steamship transport or barge transport in the waterway system of Lake Saimaa in 1950s. It defines the usage, kind of fleet, operation and costs of the abovesaid modes of transport. The investigation is mainly based on statistics of Enso-Gutzeit Oyj and the fuel office of the Finnish State Railways.

Location of the industrial enterprise sets the limits for use of the different modes of transport of roundwood. Previous decisions can influence the future choices, for instance, the capital the company has earler invested on the transportation system. Also, the type and amount of timber acquired by the company, transportation distance, time, and means of transport affect the choice of mode of transport. Those factors that direct decision-making, often lead the entrepreneur to stick to the chosen mode of transport.

Floating becomes the more inexpensive the larger the scale of operation is, and if the timber assortment is suitable for floating and water storage. For instance, dry wood is an asset for a wood export agency, and their sales have often time pressures, which rules floating out of their choices. Transportation in vessels has decreased to 4% of all roundwood haulage, but has its function as a supplementary way of transport.

The PDF includes a summary in German.

  • Roitto, ORCID ID:E-mail:
article id 4957, category Article
Yrjö Roitto. (1977). Finnish inland waterway fleet in 1975. - An analysis with special reference to wood transporting vessels. Silva Fennica vol. 11 no. 1 article id 4957. https://doi.org/10.14214/sf.a14807

In 1975 the roundwood transport in Finland, which was mostly floated in the inland waters, accounted for 45% of the total transport performance and for 25% of the total transport volume. The paper describes the Finnish inland waterway fleet in 1975. The information was collected from the material of navigation inspectors who yearly inspect the seaworthiness of the merchant ships. The number of inspected vessels was 778. Of those 495 were tugs, 118 passenger boats, 71 warping boats, and the others totalled 94. The average power of tugs was 65 kW and that of warping boats 16 kW.

The PDF includes a summary in Finnish and French.

  • Roitto, ORCID ID:E-mail:
article id 4915, category Article
Yrjö Roitto. (1975). Raakapuukuljetusten optimointi. Silva Fennica vol. 9 no. 1 article id 4915. https://doi.org/10.14214/sf.a14759
English title: Optimization of roundwood transport.

The paper deals with the optimization of roundwood transport in cases where many destinations for it exist and where several means of transport are available. It is also understood that the capacities of the factories to which wood is transported can be used at varying degree. A model was developed for a case such as Finland which sells most of its products abroad.

In the above case, the optimization of roundwood transport does not necessarily mean minimization of transport costs. What is aimed at is to obtain, by using different combinations (mill destinations and the media of transport) the maximum difference between the allowable cut (calculated) and real (actual) transport costs.

The PDF includes a summary in English.

  • Roitto, ORCID ID:E-mail:
article id 7587, category Article
Yrjö Roitto. (1976). The economic transport unit size in roundwood towing on Lake Iso-Saimaa [in eastern Finland]. Acta Forestalia Fennica no. 153 article id 7587. https://doi.org/10.14214/aff.7587

The transport unit in roundwood towing on Lake Iso-Saimaa in Central Finland comprises a tug and a raft of bundled wood with a towline between them. There are several factors influencing the economic size of the transport unit in roundwood towing. These are changing with the enterprises and along with general developments. In this paper these factors or factor groups are seen from the point of view of the enterprise. The main question is to determine the most economic combination of tug and raft size.

From the point of view of the towing enterprises the unit costs of transport are the most decisive factor. Both the size of the raft as well as the power of the tug influence strongly the unit costs. As a long-term goal a raft of about 35,000 m3 and a tug of 550 kW or more is considered to be advisable. The width of channels and sounds then allow a free passage for rafts being 36–40 m wide.

The PDF includes a summary in Finnish and in French.

  • Roitto, ORCID ID:E-mail:
article id 4711, category Article
Yrjö Roitto. (1963). Suomen sisävesien aluskanta. Puutavaraliikenteen aluksia koskeva selvittely. Silva Fennica no. 113 article id 4711. https://doi.org/10.14214/sf.a14269
  • Roitto, ORCID ID:E-mail:
article id 7537, category Article
Yrjö Roitto. (1970). Fuelwood consumption in the city of Monrovia ( Liberia) in 1965. Acta Forestalia Fennica no. 103 article id 7537. https://doi.org/10.14214/aff.7537

This paper deals with fuelwood consumption in the city of Monrovia (Liberia) in 1965. Buyers of fuelwood were interviewed at market places, relevant data were recorded, and the average size of fuelwood bundles was measured by applying Archimedes Law.

The results showed that the annual average consumption of fuelwood per caput was 1.3 solid m3, and by household 6.5–6.6 solid m3. The average annual per caput expenditure on fuelwood was $ 9.7. This corresponds to a household of about 5 persons and means a household (family) expenditure of slightly less than $ 50 per annum, which is about 8% of the total household costs. Applying the Monrovia data to the whole of Liberia, it was estimated that fuelwood consumption in the whole country was 1.62 million m3 in 1965.

The PDF includes a summary in Finnish.

  • Roitto, ORCID ID:E-mail:
article id 4728, category Article
Yrjö Roitto. (1965). Polttopuun käyttö Euroopassa vv. 1950.1960 sekä mahdollisuudet polttopuun teolliseen käyttöön v. 1975. Silva Fennica no. 117 article id 4728. https://doi.org/10.14214/sf.a14286
English title: Use of fuel wood in Europe in 1950-60 and possibilities of converting fuelwood to industrial uses by 1975.

According to the statistics, the fuel wood consumption in Europe has declined since 1925/1929, when the total fuel wood consumption was 144 million m3. In 1960 the consumption was 108 million m3. Because of insufficient statistics in the early years, the drop may even be larger than shown by the figures. The aim of this paper is to assess what part of European fuel wood removals in 1960 could be used for industrial purposes by 1975.

It was estimated that in 1975 the use of fuel wood in Europe will be about 45–55 million m3 less than in 1960 and about 10 million m3 of this amount will consist of coniferous species. It is believed that about 45 million m3 could be transferred to industrial use by 1975, and 55 million m3 is supposed to be the maximum reduction achievable by 1975. The estimates are based on the revised European fuel wood removal figures.

The new European timber trends and prospects study reveals a shortage of small-sized coniferous wood of about 25–43 million m3, depending on whether the exports from Europe are curtailed or not. The decrease of coniferous fuel wood of 10 million m3 could almost entirely be transferred for the use of industry.

A more important question is, is there demand for the extra small-size broadleaved wood. It is important to note that there is no longer any technical limitations on the use of this kind of wood for producing pulp, paper paperboard and wood-based panel products.

Fuelwood is often collected by the farmer and used near the farm. If the wood is to be used in the industry, harvesting and transport costs need to be decreased. However, productivity of the logging and transportation may be significantly improved by cutting the trees into longer lengths and professional harvesting. About 40% of the potential transfer of fuelwood to industrial uses is concentrated in Finland (7 million m3), France (5 million m3), and Italy (7 million m3). Other countries with significant potential shifts could be Romania, Spain and Yugoslavia.

The PDF includes a summary in French, German, Dutch, Russian and Finnish.

  • Roitto, ORCID ID:E-mail:
article id 4677, category Article
Yrjö Roitto. (1958). Pölkyn koon vaikutus niputustulokseen ja sen huomioon ottaminen taksassa. Silva Fennica no. 96 article id 4677. https://doi.org/10.14214/sf.a9123
English title: Effect of log size on the bundling result and how it is taken into account in bundling wage payments.

In Finland, the wage norms of forest wages have been defined by the government since 1935. However, no official tariffs have been drawn for mechanical bundling in water for floating in bundles. The aim of the investigation was to find out the correlation between the bundling result and the size of logs to be bundled, and how it affects the differences observed in earnings between the different types of devices used in the work. The aim is a more equal bundling tariff in cases where the log size is not the variable. The investigation was based mainly on diaries of bunders of Enso-Gutzeit Oy.

A tariff was formulated based on the results of the investigation. A unit tariff was obtained for bundling of timber differing in size by dividing the earnings of bundling an average timber by the unit number of logs differing in size from the average and bundled in a corresponding period. The tariff was not able to produce even earnings on all bunching machines, but a tariff that takes account log size may be recommended when the aim is an equal wage payment.

The article includes a summary in English.

  • Roitto, ORCID ID:E-mail:

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