Hodge argues against those like Bowler (1992), who view organic farming as the
only truly sustainable type of agriculture, contending that this is only true if nonsustainability
is identi®ed through the use of non-renewable resources, especially
inorganic chemicals. In opposition to this position he states that: ``...it must be
questionable as to whether organic farming, as currently practised, can reasonably
be regarded as sustainable'' (Hodge, 1993, p. 4). Factors that Hodge uses to support
his argument include uncertainty regarding nitrate losses from conventional and
organic farming, particularly in light of the diculty in controlling nutrient applications
from organic manures. Concerns over the long-term maintenance of potassium
levels in soils, especially on dairy farms, and the issue of soil erosion are also
cited. The conclusion drawn is that ``it is thus a mistake to equate `sustainable'
agricultural systems with `organic' ones. A restriction on the use of inorganic chemicals
is not a sucient condition for sustainability, but it may not even be a
necessary condition''