Grass areas on golf courses can be affected by salt in different ways; coastal courses are susceptible to flooding or being splashed with seawater, while some courses use recycled or saline water for irrigation. Additionally, certain soils naturally contain high levels of salt, which can compromise turf quality.

To ensure the long-term viability of turf areas and enhance their tolerance to saline conditions, it is essential to utilize grass species that are highly tolerant to salt. DLF, has been conducting extensive tests on their entire turfgrass portfolio for salt tolerance. All new varieties undergo regular screening to assess their salt tolerance. The testing process has been continually refined. Evaluations are carried out in controlled conditions within greenhouses. Mature plant populations are tested in five replicates. Some grass varieties have undergone multiple tests over the years to validate the data and strengthen the reliability of the results.

By incorporating salt-tolerant grasses, the likelihood of successful establishment, growth, and the preservation of desirable seed characteristics, such as visual merit, wear tolerance, and disease resistance, is significantly increased. This is particularly crucial as water resources become increasingly limited. In the future some golf courses may not have access to irrigation or may be restricted to using wastewater or surface water instead of potable water. The increasing salinity of the growth layer due to alternative water sources can adversely affect turf quality. Soil salinity poses a significant stress factor for turfgrass, ultimately leading to loss. Initial symptoms of salt stress include reduced growth, with more severe or prolonged stress resulting in wilting and eventual death of the grass

How salt affects grass growth

Overall, salt-induced stress affects multiple physiological processes in grass plants.

This table sets the levels for salinity. Above 2 mS/cm (conductivity) symptoms might start to occur. (Source: Rhoades, 1982)

Water class mS/cm g salt / litre Type of water
Non-saline <0.7 <0.5 Drinking and irrigation water
Slightly saline 0.7-2.0 0.5-1.5 Irrigation water
Moderately saline 2-10 1.5-7.0 Primary drainage water and ground water
Highly saline 10-25 7.0-15.0 Secondary drainage water and ground water
Very high saline 25-45 15.0-35.0 Very saline ground water
Brine >45 >35.0 Seawater

Grass species differ greatly in salt tolerance (see Figure 1). Tall fescues and slender creeping red fescues are among the most salt-tolerant species. Creeping bentgrasses and strong creeping red fescues also offer viable solutions for saline conditions. Resilient tetraploid perennial ryegrasses exhibit higher tolerance compared to many diploid counterparts.

Figure 1. Salt tolerance among grass species (9 = excellent, 1 = extremely poor)

Moreover, substantial differences in salt tolerance can exist between varieties of the same species. Therefore, when selecting a grass species for turf, choosing varieties with higher salt tolerance can significantly improve overall tolerance levels. The greatest variations at the variety level are observed in smooth stalked meadow-grasses and chewings fescues.

DLF labels the varieties that rank highest in salt tolerance screening with the “DLF 4salt” logo. Using 4salt® varieties increases the chances of successful establishment and survival in saline environments compared to other varieties.

Test for salt tolerance. Differences between species and varieties. The picture shows four varieties of browntop bentgrass and five creeping bentgrass varieties in 5 replicates.

Information about salt-tolerant grasses used on golf courses:

It’s important to note that even with salt-tolerant grass species, managing salt levels and providing proper irrigation and maintenance practices are crucial for maintaining healthy turf on golf courses. Additionally, selecting specific cultivars within these salt-tolerant species can further enhance their performance in saline conditions.

In summary, 4salt® serves as a guarantee for maintaining quality in saline environments.