Research paper: Forest fire and ecosystem

Interesting article and full PDF of the paper as well. Are we actually harming a forest ecosystem by not allowing fires on certain intervals?

http://munews.missouri.edu/news-releases/2016/0705-understanding-forest-fire-history-can-help-keep-forests-healthy/

COLUMBIA, Mo. – For nearly a century, forest fires have been viewed by scientists and the public as dangerous and environmentally damaging disasters. However, recent research has shown that forest fires are vital to maintaining healthy forests. While people in the western portions of the U.S. experience forest fires often and know of their value, many people on the eastern side of the U.S. do not know of their importance. In a new study, University of Missouri researchers have studied tree rings throughout Oklahoma and Tennessee to determine the history of fires in those areas. Michael Stambaugh, assistant research professor in the MU College of Agriculture, Food and Natural Resources, says understanding this history is important for managing and improving the ecology of forests in the future.

“Many forest ecosystems are fire-dependent, meaning that in order to maintain their health and vibrancy, they must be subjected to fire on a regular basis,” said Stambaugh, who is a member of the Missouri Tree-Ring Laboratory at MU. “By understanding how fire has maintained forest ecosystems in the past, we can determine the best ways to use fire to maintain those forests in the future.”

To study the history of fire in Oklahoma and Tennessee, Stambaugh examined tree rings from 332 trees in eight different sites throughout both states. Stambaugh found 843 different fire scars embedded within the tree rings and was able to determine when and how often each site experienced forest fires over the last 300 years. He found that despite having a wetter, cooler climate, forests in Tennessee experienced higher fire frequency than Oklahoma. He also found that fires existed in those areas long before Euro-American settlement, showing that fire has been important to those forests for centuries.

“The history of fire in America also is the history of humans on this continent,” Stambaugh said. “Humans have been here for more than 12,000 years and everywhere we see humans move, we see fires follow or be altered. This has been a constant for so long that forest ecology has become dependent on these fires, if they already weren’t before humans arrived. However, many parts of the U.S., especially in the eastern half of the continent, have not experienced forest fires in more than 150 years because humans have worked hard to prevent those fires. Many of those forests are now suffering because of the lack of fire to help renew the ecology.”

In order to understand the effects of fire around the U.S., Stambaugh and his fellow MU researchers are cataloging the history of fire by studying tree rings from trees throughout the entire country.

The study, “Scale Dependence of Oak Woodland Historical Fire Intervals: Contrasting the Barrens of Tennessee and Cross Timbers of Oklahoma, USA,” was published in Fire Ecology. The study was coauthored by MU Associate Professor Richard Guyette along with Joseph Marschall and Daniel Dey of the USDA Forest Service Northern Research Station located at MU.

PDF of full paper here: https://www.researchgate.net/publication/303287702_Scale_dependence_of_oak_woodland_historical_fire_intervals_contrasting_The_Barrens_of_Tennessee_and_Cross_Timbers_of_Oklahoma_USA

As with just about any question in permaculture, the answer is "it depends." But the answer could be "yes" a lot more often than the average person has been lead to believe. Hence, the imperative to learn all you can about your own little corner of the universe.

I'm reminded of Sepp's saying "If you don't want (or have) animals, then you must do the works of animals."

when the natives first came here, the land was controlled by the megafauna
the forest  composition was different than today
many of these tree species evolved with the megafauna,  each side equal strength
forest regeneration was a herd of these moving through the woods, breaking off limbs, eating the tops from trees,
stomping the rest into the ground, and dropping volkswagen size piles of poo on the ground
they had the power to keep the forest open
without this disruption, trees grow without restraint which we take as "natural"

the natives used fire (their biggest source of power) to replace these animals
we have to resort to fire and cutting and bullbozing to replace the mammoths, giant sloths and giant beavers

https://www.theguardian.com/environment/2016/aug/12/elephants-are-the-end-of-a-60-million-year-lineage-the-last-of-the-megaherbivores

Elephants are the end of a 60m-year lineage – last of the megaherbivores

When humans spread beyond Africa, they shared the planet with 42 species of terrestrial mammal weighing more than a tonne. Now only elephants, hippos and rhinos survive. The two contemporary elephant species (some scientists now say the African elephant is two distinct species, the savannah elephant and forest elephant, although debate still rages) are the last representatives of the megafauna, or megaherbivores, who have played an enormous part in shaping life on earth for far longer than Homo sapiens.

What is less widely recognised in modern-day elephants is their talent for engineering or reshaping landscapes. Such mighty beasts always have: when the fruits of the Osage orange, a North American tree, drop to the ground, nothing eats them. The tree is one of many ecological anachronisms. Its fruit evolved to be crunched and dispersed by the mammoths and mastodons that once tramped the continent; now they have vanished, the tree struggles to spread through the landscape.

Ecologists define elephants as a “keystone species,” without which ecosystems would be dramatically different. Just like their ancestors, African elephants disperse large quantities of seed over long distances: in Congo, scientists found forest elephants disperse 345 seeds per day from 96 species, typically more than 1km from parent trees. They convert forest to scrub, damaging trees and opening up areas to smaller herbivores or sun-loving lizards, which has also been shown to help lions catch prey. Elephants’ browsing of plants can reduce the fuel loads and the intensity of wildfires. Their defecation returns nutrients to the soil more quickly than seasonal leaf loss and decay.