Lichen banner photo

Growing Lichen for Caribou in the Working Forest

Caribou male - Photo by Krystal HamlinCaribou are an iconic Canadian species, appearing on the Canadian 25 cent coin. With their tall and flat antlers, they are the only members of the deer family where the males and females both have antlers. While they are more broadly known globally as “reindeer,” we more commonly refer to the species as caribou in North America.

In 2012, woodland caribou in Canada were listed in the federal Species at Risk Act (SARA), triggering a sequence of recovery plans for this species. Part of this recovery includes the development of range plans – plans that are tailored to the needs of individual caribou ranges (or herds). The range plans include actions and strategies that will meet caribou habitat needs. West Fraser has been contributing to these provincial plans in Alberta and British Columbia, through research, sustainable forest management planning, harvesting strategies, and conservation practices.

For decades, our foresters and biologists have been observing and tracking caribou along with the government of Alberta and BC. By gathering this scientific data, we can research and apply better forest management practices for caribou. Our efforts are important to do our part to help support sustainable caribou populations in Canada. For instance, we study and map caribou food sources in the forest to understand the distribution and health of their food. One example of the research that we do that is designed to inform our forest management practices involves a long-term study of ground (or terrestrial) lichen.

Caribou are uniquely adapted to certain food sources in the forest that other similar animals, like moose, elk and deer, cannot rely on. This food source is called lichen. If you are an avid hiker, you have probably walked over and around a lot of lichen. It can be crusty, leafy, hairy, rusty, shrubby, or powdery. The lichen that caribou enjoy as an important food source is primarily found on the forest floor, aptly named “reindeer lichen”.

Lichen is very slow growing and flourishes where most plants can’t. Plants need nutrients, sufficient water in the soil and sun exposure. Lichen, on the other hand, can get by with a lot less of these factors, as long as it has space to grow. Because it cannot outgrow most plants, lichen takes advantage of places that have unfavourable conditions for other plants. For this reason, lichen is found in forests where the soils are poor in nutrients and lack water, and the ground is too shaded for most plants to survive.

Caribou Lichen Research signBack in 1997, West Fraser, along with several other forest product companies and the University of Alberta conducted a study of forest management and harvesting strategies. The study measured the effect of different harvesting strategies on lichen growth. The aim was to see how we could limit disturbance of mature lichen and improve lichen growth after harvesting trees.

We experimented by logging cut blocks of various sizes in different seasons of the year and leaving 20%, 40% or 60% of trees to expose the lichen to varying levels of sunlight. We discovered that on the right soils for lichen, other plants won’t establish post-harvest. Our research question then was: what combination of site conditions and forestry practices improves lichen growth after logging?  Due to its naturally slow growth, we had to wait 20 years to get the results. So, in 2016, we re-visited those previously-logged areas with fRI Research to gather the data.

Caribou Lichen Study areaWhat did we find?

After two decades, lichen grew back to the same amount it was before we logged. Logged sites had about the same amount of lichen regrowth as comparable areas that had experienced forest fires.

We also found that after 20 years, some harvest strategies increased lichen growth. In this case, which season the harvesting took place in (summer or winter) and scarification (loosening up the topsoil to help seedlings establish themselves) were factors we found that could improve ground lichen growth.

What we can learn from this study is that we can use different harvesting strategies, such as what time of year we harvest in caribou habitat and how to prepare the site for forest regeneration in a way that better supports lichen growth. These strategies can play a role in maintaining abundant, rich lichen environments for caribou. Our harvest rotations in this region range from 80 to around 100 years, which means healthy lichen can be plentiful for caribou within actively managed forest areas, even assisting more lichen growth over time.

Learn more about how fRI Research surveys lichen growth.

Keep a lookout: West Fraser will be covering additional caribou stories in the future that will focus on vital topics of the range plans.