"American forests are under attack by invasive, tree-killing insects and disease-causing organisms that originated in other countries"............. "According to the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS), more than 400 non-native insects and 24 non-native pathogens are now permanently established in North American woodlands"........... "Some of these species have become invasive, spreading rapidly and causing significant economic and ecological impacts to the nation's forest and wildlife"............. "In the past dozen years, 28 new tree-killing pests have been detected in the country". ............. "Some of the species at risk are the foundation of ecologically unique species assemblies, such as the “high-five” pine species in the mountains of the West; hemlock groves in the Appalachians, tanbark as the only hardwood/hard mast species in the predominantly coniferous forests of northern California and Whitebark Pine, whose seeds in the Inter-mountain West are a critical food source for the remaining 750-1000 Grizzly Bears remaining alive in the lower 48 States"..............."Imported nursery stock—trees, shrubs, garden plants, roots and cuttings brought in from other countries for sale to the U.S. consumer—is one of two chief pathways that bring invasive insects and diseases into American forests"............. "Once the pests are established, their eradication is, at a minimum, costly and politically difficult"............... "Often it is simply impossible".................."The loss of nuts and berries formerly produced by vanishing or severely reduced tree species has had a poorly documented but surely substantial impact on forest wildlife species"............."At the beginning of the 1900s, the American chestnut was one of the most important wildlife plants of the Eastern United States (Martin and others 1951)"............... "With this tree practically exterminated by the exotic chestnut blight, mast-dependent forest wildlife such as white-tailed deer and black bears had to settle for inconsistent acorn and hickory nut crops as their primary food (Clark and Pelton 1999)".......... "The blight almost certainly reduced the carrying capacity of southern highland habitats for mast-dependent wildlife"............ "The blight is thought to have caused at least five indigenous insect species to become extinct or extremely rare"

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=15&cad=rja&uact=8&ved=0ahUKEwiSn7zZk-HTAhVV0WMKHdgTDg0QFghtMA4&url=https%3A%2F%2Fwww.amazon.com%2FDying-Trees-Charles-Little%2Fdp%2F0140158723&usg=AFQjCNEpXcQ5DtVSS1nRBEwoujLnSZcbOw

All over America, a range of human-caused maladies, fatal ozone depletion, ultraviolet rays, acid rain, and the disastrous aftermath of clear-cuttinghas brought tree death and forest decline in its wake. Veteran environmentalist Charles Little explores the phenomenon and concerned response (or lack thereof) . What emerges is a sobering account of the implications for the future of our planet.

Fading Forests III 
American Forests: 
 What Choice Will We Make? 
2014
Faith Thompson Campbell, Ph.D.
The Nature Conservancy
4245 N Fairfax Dr #100
Arlington, VA 22203
http://www.nature.org/ & www.dontmovefirewood.org

and
Scott E. Schlarbaum, Ph.D.
Department of Forestry, Wildlife & Fisheries
Institute of Agriculture
Knoxville, TN 37996-4563
http://treeimprovement.utk.edu/FadingForets.htm


Trees and forests are essential to the American way of life. They provide shade and shelter, jobs and
products, and clean air and water. From tree-lined neighborhood streets to national parks, Americans
count on trees to provide benefits today and for generations to come. Today many of North America’s
trees and forests are being destroyed by non-native insects and diseases. These invaders are removing
entire species of trees from our forests and neighborhoods threatening air, water, economies, and the
quality of life in our communities.

 In the past dozen years, 28 new tree-killing pests have been detected in the country.




pathogen causing oozing through bark--SUDDEN OAK DEATH in California

Over 2-5 years, SUDDEN OAK DEATH kills Oaks

Once introduced, pests impose continuing, often rising, impacts over time. For example, white pine
blister rust, introduced 100 years ago, continues to spread to new geographic areas and new vulnerable
pines. These non-native insects and pathogens can essentially eradicate species from throughout their
ranges. The USDA Forest Service’ Forest Health Enterprise Team’s 2012 report projects mortality across
90% of the basal area of redbay within 15 years.

 Some of the species at risk are the foundation of ecologically unique species assemblies, such as the “high-five” pine species in the mountains of the West; hemlock groves in the Appalachians; and tanbark as the only hardwood/hard mast species in the predominantly coniferous forests of northern California.
--------------------------------------------------

 https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&cad=rja&uact=8&ved=0ahUKEwjD6r6Ok-HTAhVRymMKHXfSDfsQFgg2MAQ&url=https%3A%2F%2Fcontinentalforestdialogue.files.wordpress.com%2F2015%2F03%2Founce_of_prevention_final.pdf&usg=AFQjCNEp_ZoueEJBgR7cKCof4m_cZHvphg

How to Stop Invasive Insects and Diseases 
from Devastating U.S. Forests
-------------------------------------

Sassafras tree dying from Laurel Wilt Disease

----------------------------------------------------

http://harvardforest.fas.harvard.edu/publications/pdfs/Foster_Arnoldia_2014.pdf

Hemlock: A Forest Giant on the Edge
David R. Foster, Editor

 Eastern hemlock (Tsuga canadensis) is an iconic tree species in northeastern
forests and the Appalachian Mountains. It has faced peril in the past but is now faced with
perhaps its most deadly threat—the invasive and devastating insect pest, hemlock woolly
adelgid. In this new book, Harvard Forest director David Foster and several colleagues and
scientific collaborators explore the history and ecology of and challenges to the majestic
eastern hemlock.

Dead and dying Hemlock via the sucking insect--The Wooly Adelgid

------------------------------------------------------
AMERICAN CHESTNUT BLIGHT

Chestnut decline, attributed to blight, is caused by an Asian bark fungus (Cryphonectria parasitica), which was unknowingly imported from Asia on infected Chinese Chestnut trees. While the Chinese variety adapted and developed a sturdy resistance to the blight, the American chestnut was no match for it.

The disease was first documented in 1904 on trees in the Bronx Zoo. The airborne blight was spread by downward winds. It spread 50 miles a year, and, within a few decades, had killed nearly three billion chestnut trees. It particularly devastated trees in the Appalachian region, where up to 25% of the trees were American Chestnuts. The spread of the blight resulted in billions in crop and lumber losses, as well as a decline in wildlife populations that fed off the nuts.

A Healthy Chestnut tree