Writings by Andrea Watts

Articles on sustainable forestry, agriculture, and other topics


Science Writing

Herbicides: an unexpected ally for native plants in the war against invasive species

U.S. Forest Service Pacific Northwest Research Station Science Findings
August 2015

Herbicides are primarily used for protecting agricultural crops from weeds and controlling vegetation competition in newly planted forest stands. Yet for over 40 years, they have also proven useful in controlling invasive plant species in natural areas. Nonnative invasive plant species, if not controlled, can displace native species and disrupt an ecosystem by changing soil chemical and biological properties. However, before an herbicide may be applied in a U.S. national forest, toxicological and ecological assessments and field testing are required to ensure it won’t negatively affect the landscape or people.

In the Gifford Pinchot National Forest, scientists with the U.S. Forest Service Pacific Northwest Research Station established experimental plots to test effects of aminopyralid (a plant growth-regulating herbicide) on both the nonnative and native meadow plant species. When applying less than the manufacturer’s maximum labeled rate, researchers found the herbicide reduced the cover of Canada thistle and other nonnatives without strongly affecting native species. Read more…

Using forest knowledge: how silviculture can benefit from ecological knowledge systems about beargrass harvesting sites

U.S. Pacific Northwest Research Station Gen. Tech. Rep. PNW-GTR-912

Sustaining the health, diversity, and productivity of national forests and grasslands is the mission of the U.S. Department of Agriculture (USDA) Forest Service. Yet managing these lands is challenging because people hold different expectations for them. Public uses can include:
• Recreation (scenery, trails, bicycle and snowmobile routes)
• Timber (structural, decorative, manufactured wood products) and wood-based energy (biomass)
• Nontimber forest products (foods, fibers, medicines)
• Sustaining or restoring natural processes (water, nutrient cycles)
• Preserving cultural and natural history (archaeological or other sites)

This booklet describes how knowledge gained from a tri-state study of good harvesting sites of a popular forest understory plant can contribute to local silvicultural decisions about tree density and levels of down wood. Read more…

Fingerprints of a forest fungus: Swiss needle cast, carbon isotopes, carbohydrates, and growth in Douglas-fir

U.S. Forest Service Pacific Northwest Research Station Science Findings
November 2014

Swiss needle cast is caused by a fungus native to the Pacific Northwest. Its host is Douglas-fir, an iconic evergreen tree in the region. The fungus does not kill its host, but it adversely affects the tree’s growth. Scientists with the Pacific Northwest Research Station and their collaborators conducted a study to learn how Douglas-fir survive even when exhibiting severe Swiss needle cast symptoms. Read more…

Unlocking the Cascadia Subduction Zone’s secrets: Peering into recent research and findings

EARTH magazine
August 2014

Delve into the latest Cascadia Subduction Zone research happening in the Pacific Northwest. Read more…

Examining Compost Tea

Acres U.S.A.
June 2014

Delve into the research and field trials on the benefits of compost tea for plant health and growth. Read more…

Bee Research Now Possible at the University of Washington

The University of Washington may have a Lamborghini lab, and not one but two ocean-going research vessels, but Dr. Evan Sugden, instructor at the University of Washington for fifteen years and long-time beekeeper, noticed that there was one educational opportunity for students missing: the study of bees and learning bee husbandry. Read more…

Is eelgrass on the move at Padilla Bay?

From shore at low tide in Skagit County’s Padilla Bay, the limp piles of eelgrass might appear the same but there are two species of eelgrass growing in the mud, the native Zostera marina and the introduced dwarf Zostera japonica. Though you wouldn’t think that the eelgrass is on the move, they are and researchers want to know how fast and where these two species are spreading throughout the bay. Read more …

Super Trees Studied in Grays Harbor

The Vidette
November 29, 2012

Grays Harbor is on the forefront of timber science. A long-term study is looking at the effects modern silviculture techniques and tree selection have on growth and future timber harvests. Read more…

English Holly: Garden and Wildlife Favorite or Invasive Foe?

Pacific Horticulture
October 2012

My first encounter with English holly (Ilex aquifolium) was making holiday decorations in elementary school. Nearly 20 years later, I encountered the plant again as a restoration volunteer with the City of Seattle working to remove invasive plants from parks and greenbelts. Himalayan and evergreen blackberry (Rubus sp.), English ivy (Hedera helix), and English holly were removed and replaced with native sword ferns (Polystichum munitum), salal (Galtheria shallon), and Oregon grape (Mahonia aquifolium). Read more…

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