The poplar species, Populus deltoides provides types which are ecologically well suited to the rich alluvial soils of the north coast. This study uses a simple simulation model and linear programming to explore the economics of introducing poplars into farm plans on this soil type. If the price of poplar timber does not fall by more than 60 per cent relative to other agricultural prices, and if plantations can be financed at discount rates less than 10 per cent, then poplar growing has considerable scope for integration with other farm activities. Poplars should be included under all the farm conditions tested, namely farm sizes between 100 and 150 acres, labour forces between one and three men per farm and a doubling of dairy profitability over the present level.