I have had the unpleasant experience of dealing with yellow nutsedge. To make a long story short, I have lived on this farm all of my life and did not realize that the yellow nutsedge was a harbinger of poor soil, that it was a member of the sedge family that includes papyrus and is favorable to growing in wet conditions until a recent experience taught me otherwise.
A fallow field was recently worked for planting. Up came the nutsedge. I was faced with the task of getting rid of it and plant potatoes or working the soil and improving it so the nutsedge could not thrive. I have opted to do the latter. Use of disking and a cover of leaf mulch and a soil amending crop hopefully will do the job.
For the first time I look at the yellow nutsedge not as an invader but as a red flag telling me that something is wrong with the soil and needs to be corrected. Outside of crabgrass, there is probably not a plant I despised more. But I have heeded the signal and am working to correct the problem by improving the soil instead of attacking the nutsedge with herbicides, which is only a band aid and not a solution.
Researching for organic methods to control nutsedge, I could not find anything that was effective. Now I know why. If you need to control nutsedge, you have a bigger problem than coffee nuts in the soil.