Locations of sterile specimens of bur reed (recognized as Sparganium angustifolium) were found in the Slovakian part of the Tatra Mountains in Pośredni and Mały Rohacki Staw lakes and in Niżny Żabi Staw Białczański lake. In the Polish part of the Tatra Mountains they were found in Toporowy Staw Niżni lake (where since 1976 they have not been found) and Toporowy Staw Wyżni lake. In Toporowy Staw Wyżni lake, fruit-bearing specimens of bur reed were observed on 18 August 2019 (Fig. 1). There were aquatic and land forms and were recognized as S. minimum (Fig. 2). The presence in the Tatra Mountains of exclusively sterile specimens (recognized as S. angustifolium) has caused difficulties with species identification. Analysis of herbarium specimens confirms the appearance of S. angustifolium in Rohacki Staw lakes and S. minimum in Toporowy Staw Wyżni lake. All specimens from Toporowy Staw Niżni lake and some of them from Mały Staw Rohacki lake differ from specimens included in species S. angustifolium or S. minimum. In those cases it is difficult to determine the species. Besides the abovementioned species, the aquatic forms of S. emersum should be taken into consideration. Final confirmation of species affiliation would require genetic tests.