Registration of ‘DALSA 1618’ St. Augustinegrass

‘DALSA 1618’ (Reg. no. CV-291, PI 702594) is a first-generation intraspecific St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] hybrid developed by Texas A&M AgriLife Research in Dallas, TX, from a cross between a drought-resistant polyploid female parent, TAES 5384 (PI 300130, GRIN National Plant Germplasm System), and a semi-dwarf shade-tolerant diploid pollen donor, ‘Amerishade’. DALSA 1618 was formerly tested as ‘TAES 5896-09’ and ‘TXSA-156’. Superior performance and quality from 2010 to 2015 in space-plant nurseries across multiple environments led to advancing DALSA 1618 to replicated trials in 10 National Turfgrass Evaluation Program (NTEP) locations across the southcentral and southeastern United States. DALSA 1618 was one of the top performers in the 2016 NTEP (2016–2020). It established faster than ‘CitraBlue’ and similarly to other tested commercial cultivars. DALSA 1618 exhibited high turfgrass quality in standard and ancillary trials and earlier spring greenup, which was generally better than ‘Floratam’. Drought resistance of DALSA 1618 was similar to Floratam (a drought-resistant aneuploid). Tolerance to moderately dense shade was tested in Dallas, TX, from 2017 to 2020, where DALSA 1618 exhibited improved shade tolerance relative to Floratam. This array of environmental testing indicates DALSA 1618 possesses a unique combination of drought and shade tolerance that would allow its use across the southcentral and southeastern United States.