Fire Ecology and What Happens After Forest Fires

Some species require fire reproduce, including California’s giant sequoias: their serotinous cones are glued tightly shut with pine resin, and require concentrated heat to release the mature seeds inside. Other species, like shrubs and annual plants, are triggered to grow by the chemical signals in smoke. In many forests, there lays a rich soil seed bank just waiting for the right conditions.

Some species (such as the Australian grass tree) are thermally insulated against fire by their bark, dead leaves, or moist tissue. Some trees (including giant sequoias), have thick, fire retardant bark that can be burned without damaging their vital tissues. Others are protected by tissues that are moister than usual, which provide thermal insulation reduce dehydration. 

Many species (including several Eucalyptus) will re-sprout if they sustain damage during a fire. In many cases, they have specialized buds that are encased in bark. When the bark burns, the buds can emerge, producing new leaves and branches. Some shrubs and many herbaceous plants rely on underground structures that allow them to come back, even if the above-ground structure has been destroyed.

Fungi can also benefit from forest fires — and the experienced mushroom hunter knows that recent burn sites are among the best places to find morels and boletes.

Fire can change the composition of the soil itself, volatilizing nitrogen and other nutrients for seeds contained in the soil seed bank. Species like Fire Lily and Indian paintbrush are just a few examples of fire-activated wildflowers.