The study was conducted in the forests of the State Enterprise “Gorodotske Forest Economy”, located in the Manevytsko-Volodymyretsky region of the Volyn Polissya in Ukraine. The annosum root rot (Heterobasidion annosum (Fr.) Bref.) impact on timber merchantability was investigated. The comparison of the cost estimation of stands assortment structure was carried out on the basis of the market value at current selling prices of the State Enterprise “Gorodotske Forest Economy” of the Volyn Regional Department of Forestry and Hunting as of 2017, taking into account the quality and the average length of the assortments. We present a comparative analysis of productivity, merchantability and assortment structure and financial value of timber volume by various assortments of pine and birch stands of the Volyn Polissya region affected by annosum root rot. We found that in the pine plantations, the overall productivity and the value of merchantable wood was higher by 42% in the control sites (areas between the fungal disease centers) as compared with those in the root rot disease centers. In the middle-aged birch-pine stands, the value of merchantable wood was higher than that in pine plantations of 34 the comparable age: by 9% in the disease centers and by 8% in control sites.
