Introduction. The most important task in urban landscaping is the creation of lawns. When organizing lawns, it is necessary to select a grass mixture that is most sustainable to recreational loads. The purpose of the research is to study the sustainability of Dactylis glomerata in ontogenesis based on the photosynthetic pigments content depending on environmental pollution degree by vehicles. Materials and methods. The object of the study is Dactylis glomerata L. Plant material was collected in the Republic of Mari El. The selection of study districts was based on traffic load data. As a result, three study areas were identified in the Soviet district of the Mari El Republic: dry mixed-grass meadow dominated by D. glomerata (control area); in Yoshkar-Ola: Pavlenko Street (low pollution area), Vodoprovodnaya Street (moderate pollution area). D. glomerata plants were studied in virginal (v) and middle-aged generative states (g2). The amount of photosynthetic pigments was measured using the spectrophotometric method. Research results and discussion. The research results showed that there were no vehicles in control area, in low pollution area 96 vehicles were observed, in moderate pollution area – 1200 units of vehicles. As pollutants in the atmosphere increase, the content of chlorophyll a and chlorophyll b in leaves v and g2 of D. glomerata plants decreases. Based on the chlorophyll content in D. glomerata in the studied areas, the following row can be compiled in descending order: control area > low pollution area > moderate pollution area. Conclusion. With an increase in the content of pollutants in the atmospheric air, the amount of chlorophylls a and b in the leaves v and g2 of D. glomerata plants decreases. That’s why it is necessary to sow D. glomerata in the areas far from sources of pollution.