Environmental Consequences of Using Fertilizer and Other Chemicals in Forest Management By ROBERT F. TARRANT Forestry Sciences Laboratory Pacific Northwest Forest and Range Experil Forest Service, U.S. Department of Agi Corvallis, Oregon PLEASE DO NOT REMOVE FROM FILES Mr. Tarrant: Thank you, Mr. Chairman, and greet- ings, friends of the forest. An anonymous scribe recently noted that unless stream pollution is halted, walking on water no longer will be regarded as a singular feat. This wry observa- tion is based on a once popular concept of pollution as having to do with introducing solid materials into water. The greatest outcry from today's concerned cit- izenry, however, is aimed not at the "old time" pollut- ing agents but against the unseen chemical residues which result from efforts to produce more goods and services for a rapidly expanding population. Defining "pollution" is not easy when we consider the semantic interactions and personal emotions in- volved. The definition I prefer is a synthesis of several that have appeared over the past few years: Pollution is any impairment of the environment that adversely affects man either directly as a living orga- nism or indirectly by reducing the value of his phys- ical possessions or his opportunity for recreation and appreciation of nature. I believe this definition is sup- portable, but I think also it illustrates why we have difficulty in communicating about the subject at hand. What are the environmental consequences of using fertilizers and fire retardants in forest practice? Most forest fire retardants contain chemicals also used com- monly as fertilizers. Thus, we can simplify the ques- tion and speak in terms of a single class of materials, chemical fertilizers. Answering the direct question assigned me for this panel discussion is relatively easy. I do not believe anyone can now define accurately the nature and ex- tent of the impact of fertilizer on the forest environ- ment. Thus, no one can say with any certainty that a problem exists. Indeed, we can hypothesize on the basis of our present level of knowledge of the forest ecosystem that fertilizing forest lands should have little or no effect on water quality. But, in terms of the popular temper, a hypothesis is no longer ade- quate to allay concern nor to assure continued use of this potentially important silvicultural tool. Perhaps an easier topic to speak of in more direct fashion would be the problem of maintaining the use of chemical tools for natural resource management purposes. I think this point is most germane to the as- signment of this panel, and I wish to develop it briefly. Maintaining an acceptable or even livable environ- ment will become increasingly difficult if presently projected population increases occur. Unprecedented population levels, rising living standards, and subsequent spiraling demands for goods and services are the causes of most of the de- cline in quality of our environment. The problem can be described, admittedly oversimply, in terms of X amount of unwanted materials generated on the be- half of each person divided by Y cubic feet of environ- ment available for dilution of this heterogeneous ef- fluent. Our individual allotment of dilution space is shrink- ing at an alarming rate. For the first time in history, a large segment of the human population has come to understand that we live in a closed system — the aquarium has finite limits adequate for several fish but it cannot satisfactorily support a doubling or tripling of population with attendant demand for living space. Thus, dilution is no longer the solution to pollution. Managers of natural resources face increasingly diffi- cult tasks in producing goods for a rapidly expanding population. During the next 50 years, the population of our country is expected to increase by two or three times, but acreage of forest lands in our country will decline. Much of our forestry research is aimed at solving the basic problem of producing more wood fiber from a shrinking land base. Economic chemicals are very im- portant tools for helping achieve the necessary pro- duction increases. The foregoing statement obviously does not tell re- source managers something new. It needs to be said, however, in case anyone does not know why chemi- cals are used in the forest. Critics of chemical use must understand the economic reasons for using fertil- izer and for controlling brush, insects, and other ob- stacles to full production of wood fiber and its ameni- ties from our shrinking forest land resource. If there are valid alternatives to the use of chemical tools, they must be offered along with criticism. An articulate, increasingly well-organized segment of the population is concerned over possible deleterious effects of economic chemicals on the local and global ecosystem. Critics of chemical practices are justified in asking,