Several pasture and field species were cultivated together with some pine species (Pinus pinea and Pinus brutia) in isolation in 1997, 1998, 1999 and 2000 on marginal clayish lands in the Aegean region. The objective was to determine the most favourable agro-pastoral options as well as erosion rates and their influence on plant performance. Pine survival rate, plant size and erosion rate were recorded. According to the results of 4-year trials, it seems that the best option, from a soil protection viewpoint, consists of mixed pastures and a combination of pasture with pine trees. However, there is clear evidence of the effect of pasture plants on pine species growth performance. Likewise, the combination Pinus spp. plus Origanum onites seems to be a promising option.