Dl. Sparkes et al., The case for headland set-aside: consideration of whole-farm gross marginsand grain production on two farms with contrasting rotations, ANN AP BIOL, 133(2), 1998, pp. 245-256
Spreadsheet calculations were used to compare headland set-aside with rotat
ional set-aside in terms of gross margin and grain production on two farms
with contrasting rotations. At Broom's Barn, Suffolk there was a five cours
e rotation consisting of sugar beet and four cereals, while at Bunny Park,
Nottinghamshire oilseed rape was the break crop, followed by three cereals.
For both farms a sensitivity analysis was used to investigate the effect o
f the proportion of the farm required to be set aside, the extent of headla
nd yield reduction and the cereal price on the outcome of the spreadsheet c
alculations.
In general headland set-aside out-performed rotational set-aside. Yields on
headlands were always less than the main body of the field, but it was on
the turning headlands where yield was particularly depressed. Thus the adva
ntage, in terms of gross margin, of setting aside the headlands was greates
t when the requirement could be fulfilled by fallowing most turning headlan
ds, but no nonturning headlands.
Generally, rotational set-aside reduced grain production more than headland
set-aside, but when the spreadsheet models were adjusted to maintain the a
rea of sugar beet, the situation was reversed. In this case headland set-as
ide produced a larger gross margin and had the greatest impact on grain pro
duction.
An extension of the analysis is to ask the question: even if set aside is n
ot an option, is it worthwhile to crop rather than fallow headlands? For ce
reals and oilseed rape the answer is in the affirmative; the gross margin f
or headlands remains positive, even when prices are much reduced, because t
he arable area payment more than offsets the variable costs. This does not
hold for crops such as sugar beet that are not eligible for arable area pay
ments.
An additional benefit from headland set-aside is its potential to enhance t
he environment through increased habitat diversity and the provision of 'bu
ffer zones' to prevent agrochemicals from drifting into hedges and watercou
rses.