Initially, loggers stripped forests on private lands of their prime old growth trees, and then followed up years later by selectively logging most of the remaining medium-large trees. While the loss of the huge old conifers was a blow to wildlife, the fact that most forest areas were selectively logged at least ensured that the post-logging habitat still contained a number of smaller conifers and hardwoods, as well as many snags and downed logs which provide valuable wildlife habitat.
In the past two decades, however, Sierra Pacific Industries (SPI) has bought out all of its competitors in the region, becoming the largest landowner in California. SPI began systematically applying widespread clearcutting, followed by bulldozing, herbicidal “site prep” treatments, and tree planting that converted the diverse natural forest into 20-acre blocks of tree plantations. These plantations reduce the forest's genetic diversity, increase fire risks, and reduce carbon storage, among other effects.
Private forest logging practices
CSERC supports the use of thinning logging methods by private companies on their private lands, but we strongly oppose widespread clearcutting.
On some sites, SPI has softened the visual impact of clearcuts by leaving a scattering of small trees or leaving a few pockets of tree clumps. Even in those situations, more than 95 percent of each 20-acre clearcut unit is still logged, bulldozed, sprayed with herbicides, and converted to even-aged tree plantations that lack diversity.
The diverse and healthy forest habitat that originally grew on those sites is destroyed, and the remaining healthy forest is severely fragmented. Many wildlife and plant species struggle to survive in the rows of densely-planted pine trees. CSERC continues to advocate for changes in California’s logging practices so that no more than a small percentage of land in any watershed can be clearcut in any decade.
This short video features local scenery, insights into the harms of clearcut logging practices, better solutions, and what you can do to help!
The environmental effects of a clearcut
Clearcutting does more than leave an unpleasant visual impact on the once-wild Sierra Nevada scenery; the forest ecosystem is damaged in a number of ways.
The clearcut logging method involves first removing all the profitable saw-log-sized trees on a clearcut site. Then, clearcuts are most often bulldozed to strip the site of shrubs, young trees, and other plants that might compete with the next crop of conifer seedlings.
Usually, herbicides are used to kill any grasses, bushes, and groundcover plants that may survive the bulldozing. Exposed soils on the now denuded hillside are prone to erosion during heavy winter rains or spring snowmelt.
The erosion process often leads to a portion of the exposed topsoil being washed off the clearcut into downslope streams and rivers. Skid trails also form gullies that funnel water and eroded sediment into streams. Large trees, snags, and downed logs that normally create refugia habitat when they fall into streams are no longer present. The originally diverse forest is converted into a more uniform tree plantation- a far less productive environment for the native plants and animals that are part of the forest ecosystem. These tree monocultures have low genetic diversity, making them less adaptable to droughts, climate change and disease, while also creating more hazardous fire conditions.
Clearcutting on an unprecedented scale
Despite the fact that logging has been occurring in the Northern Yosemite region for 150 years, the scale of forest clearing and SPI’s conversion of the forest to sterile tree plantations is unprecedented. In some watersheds, SPI has cleared as many as 3,000 acres within a decade. Overall, tens of thousands of acres of forest have already been clearcut.
Each year new Timber Harvest Plans by SPI result in additional clearcuts or similar even-age type logging treatments. The sheer magnitude of clearcutting has profound effects on wildlife, water, and scenic resources.
Blue Creek Watershed north of Highway 4
South Fork of the Mokelumne watershed
Clearcuts are followed by herbicides
Conifer tree plantations are established once all the competing vegetation has been removed by herbicides.
A natural forest contains hundreds of plant species besides conifers. Plants such as the endemic Fivespot flower shown below can be completely eliminated from an area by herbicides.
Selective thinning instead of clearcuts: a win-win solution
Thinning the forest can produce abundant lumber, while still leaving a diverse array of plants behind. Tree plantations tend to lack the fungi, lichen, ground cover, flowers, and structural diversity of natural forest areas. Most species of wildlife depend upon varied habitats that simply don't exist in tree plantations. For example, large snags and downed logs act as the "apartment houses" of a forest, as wildlife use the standing dead trees and the fallen tree trunks as homes or temporary shelter.
Additionally, thinned forests are less likely than tree plantations to have crown fires that escape fire suppression efforts and threaten other resources. Thinning can return the forest to more natural conditions, before fuels overloaded the understory.
Clearcuts threaten watersheds
If just a single 20-acre clearcut is logged, it may not affect water quality. When many large sites are clearcut each summer and fall within the local region, these widespread disturbances have a cumulative effect than can pollute many forest streams with sediment.
The next time there are heavy rains, take a drive into the national forest and look at streams flowing off the private timberlands that are interspersed with national forest lands. The streams flowing from recently cutover areas are often brown with sediment whenever heavy downpours flush soil down the steep, denuded slopes. Sediment-choked streams and rivers have a negative impact on water quality for people as well as a diversity of aquatic and plant species that depend on clean and clear water to survive and reproduce.