Whenever most people see a forest fire, they automatically think about all of the trees and bushes that are being destroyed. After the fire is over, the landscape looks like a blackened scene of desolation.
But did you know that some plants and trees actually need fires in order to survive? A number of plants rely on fire to release their seeds, eliminate competition or supply a rich layer of nutrient filled ash.
One example is the jack pine, found mostly in the very northern parts of central and eastern US and Canada. Their cones are very thick and hard. They are literally glued shut with a strong resin. These cones are referred to as serotinous which means, late blooming or opening. Serotinous cones can hang on a pine tree for years without opening up to release its seeds. When a fire sweeps through a forest of jack pines, the heat from the fire melts the resin, allowing the cones to open up and release the seeds.
Perhaps one of the most famous trees that have serotinous cones is the giant redwood or sequoia of California. Towering up to nearly 300 feet tall and 50 feet in diameter, the giant sequoia are the world’s largest trees in total volume. Their cones can contain up to 200 seeds and may take just under 2 years to mature. Once matured, they will remain in the cone and await a forest fire. The heat from the fire causes the cones to open and release their seeds.
One of the prettiest shrubs of the desert chaparrals of the American southwest is manzanita. Its bark is often a shiny reddish brown that looks like it’s been highly polished. Their hard seeds can lay dormant for several years, waiting for a fire to come its way. The intense heat of the fire causes the tough coating around the seed to split open, allowing the seed to germinate and grow.
Along the coasts of California, a number of plants rely on fires, but in different ways. Some plants like mule’s ear and iris store most of their energy in their roots and underground bulbs. When a fire sweeps past and wipes out everything above the ground, these plants respond to the heat and ash that is rich with nutrients and can be the first plants to sprout back up into the barren landscape. Other plants like ceanothus (a shrub belonging to the buckthorn family), responds to the heat like the sequoia and manzanita, releasing its seeds in response to the fire’s heat. Then you have a shrub called chamise that relies on both the root action and seed release that are responses to a fire.
Desert raisins, a bush that grows in Australia produces fruit that dry up and look similar to raisins, although they have a pungent taste with a hint of caramel. It is an important food source for the desert Aborigines. Desert raisins require smoke from a fire in order for their seeds to germinate.
Many forests rely on periodic fires just to clean them up, getting rid of old and diseased plants and trees and clearing the way for younger and healthier plants and trees to replace them.
If these plants were products of evolution, how did they evolve the reliance on fire and smoke in order to survive? If it seems hard to believe, that’s because it doesn’t make sense scientifically. The only way plants could have a reliance on fire was for God to have designed them that way from the very beginning. That also means that soon after the Fall (when Adam sinned and was expelled from the Garden of Eden), that forest and prairie fires must have occurred periodically, most likely due to storms and lightning.
Author: Patrick Fitzpatrick
A delightful nature story in ‘Dr Seuss-style’ rhyme about an oxpecker bird who removes ticks and other nasties from the skin of a giraffe, for the benefit of both.With captivating artwork, it uses these two zany characters to teach about God’s design, and about relationships, in a way that young children can easily understand and enjoy. (Primary/Elementary) 32 pages