|Picture at 5am didn't come out very good...|
We measure the EC of the water we irrigate with, we then soak greens with up to 2" of water, the next morning we measure the EC of the water exiting the green, which tells us how much sodium we flushed. This helps in determining how heavy we need to water and when we need to apply gypsum to aide in the "flushing" mentioned above. We typically water greens only as needed which normally equates to 6-10 days depending on weather. Many courses employ a similar means of monitoring their sodium levels, so this isn't anything new, just another way to better manage our facility.