Plant fossils, consisting of abraded pieces of wood, seeds, and pollen, occur near the bottom of the Armbro gravel pit in a till-capped esker near Brampton, Ontario. A radiocarbon date suggests a Mid-Wisconsinan age for the wood, whereas stratigraphic evidence suggests a Port Huron age for the enclosing sediments. The plant fossils indicate conditions similar to those now found in the southern boreal forest. Derivation of the plants from buried Middle Wisconsinan interstadial sediments to the southeast is suggested.Plant remains in glacial deposits should normally be assumed to be reworked; radiocarbon dates on such fossils do not date the enclosing sediment.

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