A study was made of the agronomic behaviour of 18 grass varieties, surface sown, after burning an upland heath community dominated byCalluna vulgaris. Complete exposure of the soil surface, the absence of competition and favourable moisture conditions provided excellent conditions for establishment. Despite this, sward development was slower than at any other site studied, and 18 months elapsed before satisfactory sward densities, and consequently a reasonable level of production, were achieved. In contrast, white clover developed vigorously from the outset. The red fescues, cocksfoots and S170 were the most promising, while the performance of most varieties was affected by one or more hazards such as frost‐heaving and summer drought. The latter aggravated the tendency of some of the varieties to produce a profusion of flowering stems and, with few exceptions, considerably reduced the colour and vigour of the herbag