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Strains of Cynodon dactylon (L.) Pers. were collected from six different climatic localities in South Africa. Under controlled conditions the strains were submitted to various environmental stress factors. Experiments were conducted to ascertain their sexual and vegetative reproductive potencies. The drought resistance test revealed that the Augrabies strain is best adapted to tolerate severe moisture stress. All strains survived a soil pH (HZO) of 2.7. The average biomass production of the Delareyville strain, at 2096 fertilizer application, was double that of the Klawer strain. Vegetative reproductive faculties of stolon scions outstripped those of rhizomes by an average ratio of 3.6:1. A seed viability ranging from 0 to 3.596 was obtained. The low percentages of seed viability indicate that the best results will be obtained if stolon scions are used to establish C. dactylon strains in denuded areas. The results indicate that no strain is superiorly adapted to resist all environmental stress factors. Consequently, strain selection for reclamation purposes will depend on the specific environmental conditions prevailing at the reclamation site. All results yielded differences between the six strains which are symptomatic of ecotypification. A hypothesis which implies that in situ studies are sufficient to predict ecotype suitability for reclamation is presented.