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The differentiated content of nitrogen in leaves was reached in birch Betula pendula ROTH grown in containers and fertilized by ammonium nitrate (NH4NO3). Negative response (high mortality and prolonged development) was demonstrated to the lower level of nitrogen in birch (B. pendula) leaves at caterpillars of the late summer to autumn aspect (Cabera pusaria L.) and to the lack of nitrogen in food (increased mortality and prolonged development) at caterpillars Lymantria dispar L. in laboratory rearing. Imagoes of Lochmaea caprea L. in the laboratory rearing preferred birch leaves with higher content of nitrogen. In a plastic greenhouse, Coleophora serratella L. and Euceraphis betulae KOCH attacked particularly birch with the low content of nitrogen in leaves (17.98/17.62 mg.g-1) whereas an aphid Symydobius oblongus VON HEYDEN attacked birch with increased content of nitrogen in leaves (29.80–32.20 mg.g-1). The results of our experiment confirm the hypothesis that spring phytophagous species prefer tissues with the increased content of nitrogen and species with late summer feeding respond negatively to the higher content of nitrogen in food.