 His planting of pine trees and of oaks , walnuts and poplars extended over 600 acres ( 2 @.@ 4 km2 ) and allowed shelter from the prevailing north @-@ west winds to allow sheep farming and the growing of wheat , while water power was used for agricultural machinery . He bought and sold land , and by 1882 Corwar was consolidated as a freehold estate of just over 5 @,@ 000 acres ( 20 km2 ) with a large mansion overlooking the river , complete with gate lodge and gate @-@ keeper . 
