Forest Thinning Needed To Save Water

Dense forests suck up surface and groundwater and dump it into the atmosphere through the process of evapotranspiration. This means that there is less water for other uses.

“There are too many trees in Sierra Nevada forests, say scientists affiliated with the National Science Foundation (NSF) Southern Sierra Critical Zone Observatory (CZO).”

A new study supported by the National Science Foundation published in the journal Ecohydrology (see press release) proclaims “Billions of gallons of water saved by thinning forests.” The study of the Sierra Nevada Mountains in California notes that “excessive evapotranspiration may harm a fragile California water system, especially during prolonged, warm droughts.”

The primary methods of good forest thinning are fire and logging.

Forest Service policy exacerbated sound forest management. Remember Smokey the Bear, “only you can prevent forest fires?” But fire is nature’s way of managing forests. Logging was largely reduced for mis-guided environmental reasons such as saving the spotted owl.

From the NSF study:

“Forest wildfires are often considered disasters,” said Richard Yuretich, director of NSF’s CZO program, which funded the research. “But fire is part of healthy forest ecosystems. By thinning out trees, fires can reduce water stress in forests and ease water shortages during droughts. And by reducing the water used by plants, more rainfall flows into rivers and accumulates in groundwater.”

Using data from CZO measurement towers and U.S. Geological Survey satellites, researchers found that over the period 1990 to 2008, fire-thinned forests saved 3.7 billion gallons of water annually in California’s Kings River Basin and …17 billion gallons of water annually in the American River Basin — water that would otherwise have been lost through evapotranspiration.

Forest thinning has increased in recent decades in an effort to stave off disastrous wildfires fueled by dense forests. This study shows that restoring forests through mechanical thinning or wildfire can also save California billions of gallons of water each year.

Perhaps we should take guidance from the first land managers in North America, the Indians. In my article “The Pristine Myth” I note the following:

Archaeological and anthropological research during the last 25 years or so, shows that much of what we thought was pristine in the Western Hemisphere, even the Amazon rain forest, is actually human-formed landscape created by the first New World inhabitants, the Indians. It seems that American Indians, from North America, Mexico and South America, were the ultimate land managers, and they transformed the land to suit their needs. They constructed the world’s largest gardens.

American Indians built cities and civilizations, cultivated forests and farms, and developed more than half of the crops grown worldwide today. Indians, rather than subsist passively on what wild nature provided, instead survived by cleverly exploiting their environment. Their principal tool was fire. They did not domesticate animals for meat, but instead used fire to change whole ecosystems to raise deer, elk, and bison.

Related story:

Forest thinning may increase runoff and supplement our water supply

A new study (“Effects of Climate Variability and Accelerated Forest Thinning on Watershed-Scale Runoff in Southwestern USA Ponderosa Pine Forests” published October 22, 2014) conducted by The Nature Conservancy and Northern Arizona University recommends accelerated forest thinning by mechanical means and controlled burns in central and northern Arizona forests. The study estimates that such thinning will increase runoff by about 20 percent, add to our water supply, and make forests more resilient.

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  1. The NAU Forestry Dept. estimates that Northern Arizona pine forests, the largest Ponderosa forests in the United States, historically were about 50 trees per acre instead of the 500-1,000 trees per acre that we currently find. A mature Ponderosa pine drinks about 300 gallons of water per day when the ground is wet. Thus, where 15% of Arizona lands are covered with millions of acres of forest, a mere 10-acres at 500 trees per acre drinks 1,500,000 gals per day, scarce water resources that do not replenish our aquifers or flow down our hills to parched southern Arizona communities and farmlands. Currently, the Tinder Fire is threatening the watershed and reservoir that Payson, AZ relies upon. The anti-logging efforts of groups, like the myopic tree-hugging Sierra Club and Center for Biological Diversity, have ensured that our forests are overgrown, unhealthy, unsustainable, and prone to bark beetle attacks and catastrophic wildfires that destroy communities, forest resources, endangered species, and watershed. Our annual wildfires cost millions if not billions of dollars to fight, and release unimaginable amounts of toxic air and water pollution that indiscriminately harms both spotted owls and children alike. AZ State Representative Bob Thorpe

    • Got news for you they would only take in that much water if it was very very dry, and they put out around 80% in transpiration. Take a water bottle, and put part of the branch with needles into it. Leave it for a day, and when you come back it will be filled with water to see what I mean. We grow over a million acres of pine and other trees on our reservation to include ponderosa. Just a hint white ash takes in the most water, and retains the most. A watermellon takes in two times it’s weight in water, and then losses up to 90% of it in transpiration.

  2. In other words we want you to destroy your forest systems so we can use every drop of the water going to them. Never mind you built citys where there was no water, and you drain the water from everywhere else now. Two old words come to mind with these stories; “Dry Up”.

  3. Seriously though,

    The elites in LA and San Fran were all too happy to support the positions based on junk science espoused by the Center for Biological Diversity and the Sierra Club when it didn’t effect them. During that time they continued to steal the ground water from east of the Sierra. That water is mostly gone. Now when they are running out of water those same elites want to use, “Real science” so they can get to, “their” water.

    There are no buildings in the Sierras to speak of. Literally just a hand full. Protect around those structures and leave the Sierras to burn naturally. And by naturally I mean fires cause by lightening and hikers.

    If it is good enough for the forests of the Rodeo-Chediski and Wallow fire it’s good enough for the Sierra.

    Sadly lawfare needs to continue. Only this time against the California coastal elite. They never understand or never care about the pain their inner anger and hate filled lawfare campaign hurt people. They have been at war against my families’ way of life for decades. Now they want us to be reasonable. If we are reasonable the damage on our way of life will continue, only in a new and monstrous way. Let their lawfare play out to it’s logical conclusion. Let California gain a more sustainable way of life to include population and it’s over use of water.

    In my opinion we shouldn’t for a second believe these people are not still actively trying to destroy your way of life.

  4. They did not domesticate animals for meat, but instead used fire to change whole ecosystems to raise deer, elk, and bison…. oh that’s the ticket, wrong meat, wrong burger, wrong guy doing the work, the whites guys are the problem.. again.

  5. Don’t let the wackadoodles from the, “Center” in Tucson read this. They will surely file a lawsuit. I sometimes think, “We don’t use science because we’re a religion” is their motto. LOL.

    Or put another way, “We don’t use science unless we made it up ourselves” is another.

    “Go lawfare!” , The wackadoodles

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