Seventy-five per cent of the food crop varieties we once grew have disappeared from our fields in the last 100 years.

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Along one 20km stretch, recalls Mr Mukerji, the road had disappeared, forcing him to drive through fields.

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They would be working the fields and his father would turn around and Albert had disappeared and they would find him "on a stump somewhere speaking to an imaginary crowd, " recalled Donald Lee Hackett, an old family friend.

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