it is a machine for the process called "corn detasseling" - first cutting the tops (tassels) of the female corn and then pulling the remaining tassels out.
You can see the step-by-step explanation of the process with the pictures in the 2nd web reference (Holloways) and the example sentence was taken from the 1st reference: a Ukrainian site selling OXBO cutters and pullers for the corn detasseling. Hope it helps :o)

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Note added at 1 hr (2013-07-29 20:52:58 GMT)
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To Igor: some in the extended family were the agronomists plus the google-fu :o)