Seed Collecting in a Changing Climate 

Those who gather tree seeds face a new reality as the weather warms

By Mark McDermid

At Forests Canada, we need a supply of seeds to plant millions of trees each year. Besides our established seed bank, we rely on seed collectors who gather everything from maple keys to oak acorns to pinecones each year, and they are coming up against some new challenges.

We've all noticed warmer falls. Not that long ago, we used to have a frost by mid -September. Now, we may not see any frost well into October, and these warmer falls are making tree seed collection more difficult.

Pinecones, for example, are difficult to collect directly off trees because they are near the tops of tall trees. It’s hard, even impossible without specialized equipment, to get up to the cones.

So, for many years, our seed collectors have walked through the pine forests each fall to seek the caches of cones made by red squirrels. The squirrels cut the mature cones from the treetops and stash them on the forest floor to eat over winter. Our collectors take a portion of the cones from these caches and replace what was removed with peanuts, sunflower seeds or other high protein/high fat snack, so the squirrels don’t go hungry.

Warmer weather, however, forces us to think about new ways of doing things. For example, we collect cones in Simcoe County, and other regions in Central Ontario, on sandy sites, which are typically warmer and drier. In warm weather, cones and seed will mature quicker. The scales on a cone, which stay closed longer in cool, moist conditions, can open and disperse its seed. If you pick up a cone and the scales are open, there is a good chance that most of the seed in that cone has been released and you are too late!

In recent years, the timelines and opportunities to collect cones are narrowing – a common sentiment I hear when I talk to people involved with seed collection across the country. This is also why it is incredibly important that we learn from these potential climate impacts on our natural landscapes to ensure the millions of new trees planted each year in Canada have the best chance for survival.

With the collaboration of our longtime Forests Canada partner and certified tree seed collector, Chris McGee, we are able to adapt and respond to landscape-level challenges in seed development and collection.

Chris has worked with Forests Canada as a seed collector for many years. As with many of the seed collectors Forests Canada works with, previous generations of seed collectors shared their knowledge with their children and grandchildren. This was the case with Chris and his brother Colin, who learned the skill from their father and grandfather. Well versed in many forested areas across Southern Ontario, Chris and I recently collaborated on several seed-related initiatives that prioritize the long-term health and survival of Canada’s future forests. This includes identifying collection opportunities with good potential, and monitoring and forecasting these crops throughout the season to ensure a consistent, high-quality supply to support Forests Canada’s restoration work.

Once a site is ready for collection, we deploy collectors right away to capture the crop. Some tree species, like Tamarack, can be a challenge. Squirrels rarely cut Tamarack cones, so we must find collection areas where we can reach the cones from the ground, or use orchard ladders, at the precise time they are ready for collection. With other conifer species, we can team up with municipalities and/or forestry companies to collect seed from trees that are being harvested.

Seed collection training, such as the certified seed collector course offered by the Forest Gene Conservation Association, is an important part of the overall knowledge base required to collect seed in a sustainable, accredited manner. Mentorship and hands-on training are also critical elements to develop a credible, long-term seed program – an investment Forests Canada has fostered over the years.

It is thanks to the commitment, ingenuity and adaptability of Forests Canada’s seed program, and the experience of our growing network of seed professionals, that we have been able to build and maintain a bank of over 200 million high-quality, source-identified seeds for our restoration work. By investing in Canada’s seed collectors, nurseries, and planting partners, we are supporting the entire restoration network, and that is integral to ensure the long-term health and resilience of Canada’s forests today, and for generations to come.