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Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
A seed from the Norway maple (Acer platanoides). The major grid spacing is 1cm. These seeds are wing-shaped, typically 3.5–5 cm long and with a chord of 1 cm. Their mass is between 100 and 200 milligrams when dry.