AbstractA field investigation into the effect of slurry seeding on the dry‐matter yield and persistence of an Italian ryegrass sward was assessed over a 3‐year period (1984–86) under a regime of three cuts per season combined with sheep grazing in early spring and late autumn. Results showed that slurry plus seed treatments produced up to 30% more herbage dry matter and a significantly higher tiller density than where no slurry or seed were used. Slurry application with and without seed also reduced the proportion of weed grasses (mainly Poaspp.) in the sward. It is concluded that slurry seeding is a useful technique for extending the productive life of an Italian ryegrass