closeup view of fresh horse chestnuts (aesculus hippocastanum) unripe and partly brown

aesculus hippocastanum fall horse chestnuts spanish chestnut aescub autumn background barb beautiful biology botany brown buckeye castanea castor closeup conker tree environment escin european foliage folk medicine forest fruit fruits horsechestnut nature october outdoors prong quill ripe scavenging seed hull spike spine thorn unripe vascular protection white view fresh partly development green shell brown