Acknowledgements
We are grateful to the many people who contributed their ideas, advice, and labor to the conception, design, and establishment of this experimental site. Specifically, we thank Jennifer Dacosta, Madison McCaig, Mya Rice, Lincoln Rowlinson, and John Schnare for help with trial maintenance and tree measurements, and Florentin Jaeger for assistance with soil sampling. This research was supported by a Discovery grant (RGPIN-2015-06060) from the Natural Sciences and Engineering Council of Canada and a Canada Research Chair to PMA.