Evaluation of squared timber and log products in the Hyrcanian Forests of Iran

The forests located in the northern areas of Iran are known as Hyrcanian Forests and are distributed across three provinces, namely Gilan, Maznadarn and Golestan. These provinces are situated in the north of Iran near the Caspian Sea. Timber products in the said forests during the last two decades were markedly different so that the total timber harvested in the first decade was 1.6 million m3 on average, however, in the second decade it nearly amounted to 1 million m3. Two major timber products of Iran are studied and compared in this research, namely logs and squared timber. Squared timber products averaged 10.7% during the first decade, but they fell to 7.3% over the second decade. Apropos of log products, they reached 20.9% and 29.2% over the first and the second decade, respectively. Analyses of the data indicate the following converse linear equation between squared timber products and log products during the 20 years of study: Y =-0.359X + 18.065 (Y = log products, X = squared timber, R2 = 0.768).Accordingly, any increase in log products at a time caused the squared timber products to decrease at the same time.