A trial to determine the lime requirement for reseeded grassland on a peaty hill soil

Lime was applied in summer 1981 at rates up to 201 ha −1 prior to reseeding an unimproved peaty hill soil. A marked pH gradient with depth developed showing that 3 years after application lime had very little effect below a depth of 5 cm. Soil pH values for 0–7.5 cm samples were: nil lime‐4.2; 1 t ha −1 ‐pH 4.3; 2 tha −1 ‐pH 4.6; 4 t ha −1 ‐pH 5.0; 6 t ha −1 ‐pH 5.6. In the 0–2.5 cm layer pH values were much higher. In all years at least 80% of maximum yield was achieved from an initial application of 21 ha −1 lime. Botanical analysis showed that maximum persistence of sown species, perennial ryegrass and timothy, occurred from 2 t ha −1 lime; 6 t ha −1 lime was necessary for maximum persistence of clover. Lime application had only small effects on the mineral composition of the herbage.