Agropyron, Couch Grass, quack grass

 Dried root or lower stalk is good as tea or fluid extract for sodium retention due to aldosterone excess. Diuretic. Reduces sodium and fluid.

From  SPECIFIC INDICATIONS FOR HERBS IN GENERAL USE Third edition Michael Moore:

AGROPYRON REPENS Chronic renal weakness with inflammation. Cystorrhea, acute with urethral discharge. Cystitis, urethritis, for pain. Cystitis, urethritis, with mucus in urine, backache, cramps; or with pain from gravel and alkaline, phosphatic urine. Acute dysuria with pain in back, difficult urination. Deep seated kidney pain accompanying primary treatment for nephritis. Hematuria with pain on urination. Ureteralgia. Sacral and lower lumbar pain with urethral mucus discharge. Phosphaturia with pain in kidneys. Chronic pyelitis, with colic. Acute prostatitis, with irritable bladder, dribbling. Subacute prostatitis, enlarged, without inflammation.