Each Friday, the Society of American Foresters sends out an email with links to news articles relating to forests and ecosystems. This week's batch contained two articles about disappearing mountain meadows. We might think of meadows as unchanging locations full of water, grasses, and wildflowers. But, like nearly everything else in nature, the truth is far more complicated.
The Daily Bucket is a regular feature of the Backyard Science group. It is a place to note any observations you have made of the world around you. Insects, weather, meteorites, climate, birds and/or flowers. All are worthy additions to the bucket. Please let us know what is going on around you in a comment. Include, as close as is comfortable for you, where you are located. Each note is a record that we can refer to in the future as we try to understand the patterns that are quietly unwinding around us.
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As natural succession slowly but steadily rearranges landscapes, it does not magically exempt meadows from its work. Trees will gradually encroach; and as they do, they begin tapping the groundwater that makes a meadow what it is. Meadow plants lose their water source, and their sunlight too. Given enough time, some meadows will become forests.
Historically, succession has been held in check by fire. Whether the source was natural or from Native Americans, fire would take out the encroaching trees. Generally the fires occurred frequently enough that they did not kill all of the adjacent trees, and the encroachment would begin anew.
We are continually learning about the unintended consequences of the past century of fire suppression. One of those consequences is the gradual loss of meadows.
Friday's news feed had two stories about small-scale efforts to reverse that trend. First up is an article by Valley Public Radio, An Ancient Native American Drought Solution for a Parched California.
In a cooperative effort with the US Forest Service, North Fork Mono Indians removed trees and invasive plants from a meadow southwest of Yosemite.
By removing trees, shrubs and nonnative plants in what was once a meadow, Goode believes the forest won’t consume as much water. It’s a practice passed down generation to generation in his tribe. Thinner forests means snowmelt will pool in mountain meadows and eventually seep into aquifers rather than consumed by the trees. Second, fewer trees and brush means less chance of large wildfires.
The amount of water that can be saved by thinning forest and meadows is still unknown, but according to a University of California forest study thinning could yearly add up to 16 percent more water flow out of the Sierra Nevada and into California’s water supply.
Next up, an article from Plumas County News, Collins Pine makes progress in restoring Marian Meadow. The location is south of Lassen Volcanic National Park, near the town of Chester. Collins Pine has begun a research project where trees will be removed in stages, and the effect of each stage will be measured.
Studies have shown that Northeastern California has lost significant portions of its large alpine meadows, [forest manager Jay] Francis said, “So what we’re trying to do is nudge this area back towards what nature had intended it to be.”
The students went out prior to winter 2014 to establish monitoring points where they installed equipment to measure the water table and also the rate of water flow coming from the meadow. Last winter the second year of gathering seasonal data was completed.
Francis explained that with the exclusion of any natural fires in the past hundred years in the area, conifers have been allowed to encroach into the meadow, adversely converting the watershed and drying it out.
“We’ve always had conifers around the perimeter of the meadow, but as the species invades it established itself and continued to move into the center of the meadow,” with more trees absorbing more of the groundwater.
Both articles are worth reading in their entirety.
And here are two bonus stories relating to trees in the Pacific Northwest. For those who live in the Portland metro area, one of the gateways to the Cascade Mountains is through Estacada and along Oregon Highway 224 which follows the Clackamas River into the mountains. Last September, a fire broke out during dry windy conditions, and quickly burned more than 5,000 acres. From The Oregonian, Forestry experts say commercially thinned areas fared better in 5,524-acre 36 Pit Fire.
The fire burned in uneven patterns – almost a mosaic – that created side-by-side contrasts that depended largely on terrain and conditions in the woods. Flames shot up steep slopes unabated, but slowed to a crawl on flat areas. In some areas, the fire burned close to the ground, blackening the tree trunks, but didn't get up into the trees' crowns.
But one thing was clear: Stands that had been thinned by selective logging fared far better than areas that hadn't been managed.
"Forest management definitely made a difference," said Mike Haasken, forester for the Oregon Department of Forestry's Molalla Unit. "Areas where there was commercial thinning, the fire slowed down."
Once again, this is part of the legacy of fire suppression. Unbroken stretches of dense forests full of ladder fuels are not the historical norm for the West. It used to be that fires burned frequently enough to keep the fuel loads down, and create a mosaic of forests of varying ages and densities.
In the absence of fire, thinning is the next best means of reducing fire danger. In the megafires that incinerate huge swaths of land, thinning makes little difference. With the smaller fires, the thinned patches give the trees a chance to survive, and also provide firefighters with opportunities to control the blaze.
Finally, this article covers a topic that has been mentioned in recent Daily Buckets. The handsome, red-barked tree known as Pacific Madrone is in decline in some areas, apparently due to a combination of stess from drought plus a fungus. From the Mail Tribune, Blight strikes hardy madrones.
Known for their orange-red trunks and branches, the evergreen trees have been afflicted with various fungal blights that attack the waxy leaves. ODF officials have identified the most common type of blight as being caused by Phacidiopycnis washingtonensis that was noticeable throughout Oregon in 2014 and continues to be noticeable this year.
Usually, the trees rebound after being stricken by blight. But forestry officials have noticed some branches have died, and they're unsure whether successive years of blight could cause the trees to die completely.
Now it's your turn. All comments, observations, and photos of the natural world are encouraged.
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