After beef cattle have grazed on pasture land for a year or two, they are usually sent to feed-lots, where they are fattened on a diet of hay and corn to prepare for slaughter.

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Biofuels -- Rising demand for food, which competes with biofuels for arable and pasture land, and a popular backlash against the subsidies they attract, will constrain the long-term potential for biofuels production using current technology.

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The Earth does not have enough clean water, good pasture land or even livable space along coasts to have everyone in, say, the poorer areas of western China and central India living and driving the way we do in, say, northern Virginia.

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As a result huge amount of marginal land has been taken in as pasture, overgrazed to the point of exhaustion, and now farmers are being forced to watch the topsoil literally blow away on the spring winds.

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Sadly, proud traditions fill no stomachs, and since their illiterate forebears signed away 90% of their land to the British, the Masai now have too little pasture to sustain a swollen population.

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Unowned forests are unprotected, which is why the grileiros, or land-grabbers, of the Brazilian Amazon rainforest can so easily turn it to pasture.

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