Agriculture Reference
In-Depth Information
if American farming were horse-powered today, it would take 250 million horses
to match our tractor and harvester engines. We'd need 740 million acres of land to
feed the horses - twice as much arable land as the United States has. Instead of ex-
porting food to densely populated Asian countries, the United States would be hard
put to feed itself.
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Although this statistic is meant to illustrate the inefficiency of horses, it doesn't take too
much thought to see that it actually reflects the inefficiency of US agricultural machinery
and its extravagant fossil fuel expenditure. 250 million horses is almost one horse per US
citizen, enough to plough 2.5 billion acres which is enough land to feed the world. If the
USA is employing that much horsepower to produce its crops, it needs a radical rethink.
The most reliable calculation probably comes from Jan Jansen's study of the agricultural
economy of a Swedish village in three years during the 20th century. In 1927 there was
one working horse for every 8.4 hectares of land, and horses consumed 18 per cent of all
ates of the amount of farmland devoted to horses in days gone by because crop yields have
increased dramatically, while the area which a horse can cultivate has probably increased
somewhat as well, thanks to improved technology. In 1920, one and a half times as much
land was put down to oats as to wheat (whereas now the oat crop is negligible) and this
was a reflection of the need to feed horses. But in 1920 the average yield of oats was 1.7
for non-organic, and it is even higher in Ireland. Leaving aside the hay and grass that will
always be a proportion of a horse's feed, we now need roughly a third as much arable land
to feed a horse as we did in the 1920s.
So how much land does a working horse need nowadays, and how does that compare
with a biofuel tractor? It is difficult to calculate because it depends how much oats and how
much non-arable grass it is getting. Ken Laing advises: 'A starting point would be to allow
one tonne per horse per year for a horse worked frequently' with the rest of the feed con-
sisting of pasture or hay. One benchmark for comparison is to take a fairly high yielding
field of wheat and determine how much horsepower and biofuel power it could, theoretic-
ally, generate. Wheat yields in the UK are around eight tonnes per hectare, against 6.5 for
oats (which is what horses prefer); but since horses also eat grass from non-arable areas,
and since the feed value of oat straw is more than of wheat straw, the figure of eight tonnes
is reasonable. Eight tonnes of grain, grown on a hectare of prime land, will provide 22 kilos
of grain every day for a year, which is enough in terms of calories (72,000 per day) to keep
two horses working at a moderate pace.
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Two horses are normally agreed to be capable of cultivating ten hectares. According to
horseman Charlie Pinney, 'when farm horse numbers were at their highest, the generally
