A possibility of applying the Dahl-Lea back calculation method to growth rate assessment of roach, bream, pike, and zander inhabiting open inland waters in Poland was investigated. Scales were selected for the purpose due to their availability, legibility of annual rings, and a high reliability of readings. The scales with which to investigate the body length-scale caudal radius relationship in bream and roach were collected from the fish caught in heated Konin lakes (the Licheńskie, Pątnowskie, Wąsowskie, Gosławskie) and from the coastal lakes Łebsko, Gardno, Bukowo, and Jamno. The relationship in pike was explored on scales collected from individuals caught in the coastal lakes Łebsko, Gardno, and Bukowo and from a small (about 40 ha), shallow (a kind of a natural pond) Lake Warniak in the Warmia-Masurian Lake District. Scales of zander, to be used for investigating the body length-scale oral radius relationship, were collected from individuals caught in the coastal lakes Jamno, Łebsko, Bukowo, and Kopań. The scales were collected in various years of the second half of the 20th century, during the autumn-winter season after the fish growth had slowed down. The analyses performed allowed to contend that the Dahl-Lea method of back calculations, necessitating a direct relationship between body length and scale radius, can be applied to bream and roach. In pike, the body length-scale caudal radius relationship is linear, but the free term in the equation derived (y =  22.607x +  2.6217) suggests the Rosa Lee method as more suitable. In the zander populations studied, the body length-scale oral radius relationship was linear as well. However, as the sample was not representative (a narrow range of fish sizes and low numbers of fish in various size classes), the relationship was not sufficiently reliable. For this reason, the results of growth rate calculations with the method used would carry a too heavy bias.

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