The relative unimportance of certain soil properties as dererminants of growth of forage oats

In two field experiments at Armidale, in the northern tablelands of New South Wales, on a range of grey-brown and yellow podzolic soils, it was shown that production of forage oats was largely independent of soil morphological properties. The properties recorded were colour and thickness of horizons, proportion of ferruginous inclusions, bulk density of A horizons, and several properties associated with organic matter content. In the first experiment, under fertilized conditions, yield was related to moisture supply, and in the second, without added fertilizer, yield was related to per cent moisture content at field capacity, exchangeable calcium, and darkness (Munsell value) of the surface soil. Interrelationships between soil properties were mainly as a result of organic matter content. These findings have implications in soil surveys for land use, sampling procedures, and field experimentation.