Wheat Seeds in Thatched Roofs

English botanist John Letts has found thatched roofs are a very rich source of historical seeds. Seeds of rivet wheat, bread wheat and rye have been found in 250 thatches dating from the 15^th Century in Devon, England.

The seeds have survived because the houses were built as open halls with a central fireplace. The heat kept the seeds dry and the smoke prevented them from rotting. The fact that some thatches consisted of straw from rivet wheat, bread wheat and rye woven together, has lead Mr Letts to speculate that medieval farmers grew them all in the same field. This would have minimized risk – if the season was dry, the rye would grow well, but if it was wet, the wheat would flourish.

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