Populus candicans and the Balm of Gilead

Bud exudates of some poplars are compared using GC-MS. P. candicans resembles P. balsami­fera. A sample of "Balm of Gilead" purchased in Oxford proved not to resemble its supposed source, P. candicans. Instead it was similar to P. nigra, from which it was presumably collected in Europe.