That's because the native flora, largely buffalo grass and big blue stem grass, is notable for sinking unusually intertwined roots.

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Steering between stone weirs and hidden eddies, the boatman points out wildlife along the riverbanks: shelducks in the shallows, water buffalo in the grass, a grey heron hidden among the reeds.

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Now zooms out and in to a buffalo and egrets chillin' in the grass.

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