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The same structure that gives cedar its excellent insulating and sound suppressing qualities makes it a lightweight wood, easy to handle and craft for both the professional and do-it-yourselfer. Cedar is a pleasure to work with using either hand or machine tools. The wood can be cut, shaped, planed, sanded, nailed and glued easily. It is free of pitch and resin and it finishes to a richly glowing surface that can be enhanced with semi-transparent or full-bodied stains.
Since moisture is a factor in the checking process, the depth and span of the checks will vary upon placement outdoors. Direct sunshine contributes to the drying of logs, therefore widening their cracks. Moisture and indirect light will shrink cracks. Although White Cedar possesses much of the same cell properties of western red cedar, (which makes them both the desired woods for outdoor use), it contains much less of the natural acidic tannins that help to preserve western red cedar. Therefore white cedar will not last quite as long as western red cedar wood.
Characteristics of White Cedar LogProducts:
It’s normal for all cedar log furniture to endure the natural process of checking as the wood “seasons”. Checking occurs as a wooden log releases moisture across or through the annual growth rings. It does not affect the structural performance or integrity of the wood. All logs which contain the heart of the tree will develop lengthwise cracks or checks. The check never goes deeper than the heart.
Skim the text 3. Write down an annotation of the text.
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Wood Production
The wood production function of the forests is a very important factor for the economy of both the Republic of Buryatia and the Irkutsk Oblast. It provides employment for many people and produces roundwood logs for export as well as raw materials for several wood processing industries. There are 2 pulp mills in the area, and hundreds of saw mills and other wood processing industries (e.g. furniture, window and door frames, prefab houses). Siberia, including the Baikal region, has always been a net exporter of wood, primarily to western Russia, but recently markets are developing in the south and east (Mongolia, China, Japan).
Large scale industrial forest utilisation started after the second world war, and was mainly geared at producing high volumes of wood. The common harvesting method consisted of clear felling areas from 50 up to 200 ha, using the tree length method. Thinning and intermediate felling are hardly practised at all: these are considered more as silvicultural tasks under the responsibility of the leskhoz.
The logging companies (lespromkhoz) were primarily interested in cutting old growth by final felling through clear cutting. Their harvesting and logging machinery was too heavy and robust to be used for more delicate selective felling operations. Furthermore, clear felling is dominating in the leasing system, although also other systems for final felling are recommended in the instructions.
As a result, much of the forests are characterised by an unbalanced forest utilisation, with heavily cut forests along the main transport networks (rivers, roads and railways) (figure 3.4) and practically untouched old growth forests in remote and inaccessible areas. Much of the heavily cut forests were subject to natural regeneration with a large share of undesirable soft broad-leaved species (aspen and birch), due to the large size of clear cuts and the absence of seed trees. Gradually, following natural succession, these areas have developed into mixed forests of 30 to 50 years of age, which require heavy thinning operations in order to produce saw logs in the future.
One of the main issues in Russian forestry is the single focus on cutting old growth forests while neglecting the young re-growth on these cutting areas, which are all located adjacent to transport networks.
As a result, logging companies have to go ever farther into remote areas with old growth forests to satisfy the wood demand.
In the long run Russian forestry cannot continue to base its entire wood raw material supply on harvesting old growth forests. It is essential to increase productivity (through pre-commercial and commercial thinning) of the nearby located logged forests.
This also transpires in the concepts of “main use” and “intermediate use” of the forests. Until recently, some 95% of all wood production were obtained by main use, which means something like: using the old growth forest mainly for wood production by final felling of the forest cover.
