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The hemlock woods at the Harvard Forest are filled with scientific apparatus to monitor threats similar to the one that killed chestnut trees. The forest, the soils, and the streams are all gauged and monitored, and each tree stem is marked and identified to signify that the stem's vital details have been recorded and stored in a digital database. This concluding chapter presents the authors' final thoughts and lessons learned in their explorations of the hemlock.

This chapter details the author's field notes from the H. J. Andrews Experimental Forest. The author was awarded a two-week residency in the forest through the Spring Creek Project, which is administered through Oregon State University. The project began in 2003 and will continue until 2203, fully funded. The mission is to keep a “Forest Log” of ecological reflections for two centuries. The chapter then recounts the author's identification of the trees and plants. The trees include Douglas-firs, western hemlock, western red cedars, and Pacific silver firs. Meanwhile, the plants include the Low Oregon grape, trillium, and Linnaea borealis, better known as “twinflower.” However, there were no blooms to speak of at the end of October.

The hemlock, a long-lived evergreen tree, suffered the heaviest decline from the landscape destruction following the arrival of Europeans in North America. Since the days of the Civil War, the hemlock has reasserted its way into the forests and returned to its prominence in the northern landscape and the eastern forests. This chapter studies the hemlock's past, present, and future, beginning with its prominence following centuries of abuse and exploitation. By examining the hemlock, important issues about forest conservation can be addressed. The chapter also describes the impact of the spread of hemlock woolly adelgid, an insect that found its way to the forests of North America and which is threatening the existence of the hemlock trees. It compares the advancing decline of the hemlock to that of chestnut in the early twentieth century and of the hemlock 5,000 years ago and then following European settlement.

This chapter discusses the hemlock's distinctive characteristics, including its wide-ranging effects on the environment and other organisms. The hemlock's dense foliage allows almost no light to reach the ground, creating a distinctive, cathedral-like atmosphere in the forest. What makes the hemlock special is its ability to survive deep shade. Scientists recognized that the hemlock's great shade tolerance comes from its unsurpassed efficiency in light absorption, especially at low levels. In its extreme shade tolerance, the hemlock is rivaled only by two other eastern trees: American beech and sugar maple.

Foundation species build and define ecosystems and maintain a wide range of services: clean air and water, wood products and wildlife, and solitude and inspiration. This chapter discusses the challenges to ascertain whether a species is foundational in any ecosystem, and then identifies the hemlock as a foundation species, including its nature and role in the ecosystem.

The sudden decline of the hemlock 5,500 years ago is a striking feature that appears in all paleoecological records. The records from most New England lakes feature shifts in vegetation along with changes in regional climate since the last glacier receded. The hemlock then recovered almost completely, following a period of regional scarcity that lasted nearly 1,500 years. This chapter examines this ancient dynamic to explore the patterns, causes, and consequences of an earlier catastrophic decline of the hemlock.

Tree declines from invasive insect pests generate a variety of short- and long-term effects on forests along with impacts on ecosystems and wildlife. This chapter discusses the hemlock woolly adelgid's arrival at the hemlock forests in North America and describes the efforts to document the rate of adelgid infestation, hemlock decline, and environmental and vegetation changes.

The Harvard Forest Hemlock Removal Experiment, also known as Cut or Girdle, is a long-term experiment set up at Harvard Forest with the goal of understanding how forest ecosystems respond following the removal of a single foundation species. This chapter discusses the results of the Cut or Girdle experiment conducted in the New England landscape and compares it with regions across the United States. With Cut or Girdle, it is possible to determine how a representative New England forest changes, depending on how the hemlocks are killed and how quickly they disappear from the forest.

This chapter discusses the use of simulation models to address ecological questions. Ecological modelling refers to computer simulations of ecological processses represented and linked together using mathematical and statistical functions. These models enable scientists to generate hypotheses about the ways ecosystems work. The chapter focuses on a forest model that has been used to anticipate the effects of adelgid-induced deaths of hemlocks in eastern North America.

The eastern hemlock is identified as a foundation species—a species that creates its own ecosystem and is intimately linked to the majority of other species in the system. This chapter discusses the characteristics of the eastern hemlock as a foundation species. Studies conducted have shown that the loss of hemlock in hemlock-dominated systems, whether from adelgid or logging, results in both short-term and long-term effects to associated plant and animals species along with shifts in ecological processes.

This chapter discusses issues of conservation and management with hemlock serving as an effective focal point, and provides insights on land management and ways to protect forests in the eastern United States. It argues that conserving at least 70 percent of forest landscapes is possible and sensible to ensure the continuity of natural areas and forest resources.

Thoreau observed the shape, color, texture and stance of trees. His eye took in all—root, trunk, bark, branch and crown, leaf, blossom and cone. He knew them all over Concord—birches, basswoods, hornbeams, pines and hemlocks in pastures and on hills. He loved big trees, like great pasture oaks and pines that rose like spires in the forest. But he loved small or common trees no less. His eye never tired of the details that differentiate one tree from another. “A tree seen against other trees is a mere dark mass, but against the sky it has parts, has symmetry and expression.” Examining those details was more than observation for him. It was an act of contemplation.

This chapter examines Americans’ hesitant embrace of physician-assisted suicide (PAS). After considering the right to refuse life-sustaining treatment and the general rejection of physician-administered euthanasia, the chapter explores the history of PAS and the legal response to it in depth. It discusses the activism of Derek Humphry and Jack Kevorkian. It analyses the Supreme Court’s 1997 decision in Washington v. Glucksberg, which denied the existence of a substantive due process right to PAS. The chapter also describes the 1994 passage of the Oregon Death with Dignity Act and the sputtering success of such measures in other states. It analyzes the opposition to PAS by both conservative religious groups and left-leaning disability activists and shows how the same anti-establishment suspicion that bolsters support for freedom of therapeutic choice in other contexts can provoke opposition to assisted suicide.

Our family dog is an Andalusian bog hound, a perfect specimen of his breed. His appearance and behavior are typical of bog hounds, but for those readers not familiar with them, a description is in order. An unusually handsome animal, he stands 22 inches high at the shoulder, maintains a trim weight of fifty-seven pounds, and has a short, smooth coat of a rich, red-brown color and a well-proportioned head with strong jaw musculature and brown eyes. He is extremely fast, and while running in open areas makes frequent, stiff-legged bounds straight up in the air. This may be an ancient canine technique of cooperative pack hunting, probably serving both to stir up prey and to provide a view over tall grass. His name is J. D., given by my daughter Kate because the way he moves his hindquarters when he walks reminded her of a character of that name played by Brad Pitt, in the movie Thelma and Louise. J. D. is exceptionally affectionate. He has never been known to growl or snap at anyone, although he once took exception to a recording of Paul Robeson singing “Old Man River.” When permitted, he greets people by standing on his hind legs with his feet on their chest (or shoulders, if they are short) and gazing directly into their eyes. He rarelys hows affection by licking; as a special mark of favor he may take a handor arm into his mouth and chew gently. His distaste for swimming—as opposed to walking in muck—is characteristic of bog hounds, especially Andalusians. We tested this behavior during a trip along the headwaters of the Passaic River, in northwest New Jersey. Coming to a deep pool, my wife, Joan, J. D.’s favorite, jumped in and pretended to be drowning. J. D. watched from the ban kin great agitation as she splashed and screamed, but he made it quite plain that if anyone were to jump in and save her, it would have to be me, or perhaps another dog. It is hard to judge J. D.’s intelligence.