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en sciences et technologies pour l'environnement et l'agriculture

Root systems of 3 balsam fir stands were excavated in the boreal forest of Quebec.• Frequency and conditions conducive to natural root grafting were characterized.• 36% of trees were grafted with another tree, corresponding to 1.3 grafts per tree.• Tree proximity and number of roots per tree increased root grafting frequency.• Grafts formed between trees from 12 to 106 years old.