japonicus
commented
6 years ago I've added this to the DDb, but perhaps misspelled:
It's not clear to me what the spelling ought to be, Koch published the taxon as Carya illinoënsis, (https://www.biodiversitylibrary.org/item/60407#page/617/mode/1up) but IPNI (and most usage in google) gives C. illinoinensis (http://www.ipni.org/ipni/idPlantNameSearch.do?id=442167-1)
I have found this tree a couple of times recently in VC12: Isington SU7732 4280, a large tree beside stream on farmland, ARG Mundell 24 Jun 2017. The Pecan, but surely planted here. Also several trees in wood behind Litchfield Church, found ARGM 3 Aug 2018, one even had a Pecan nut due to the hot dry weather. Not on MapMate or the DDB. I would like it recorded on my MapMate database.