At the Threshold of Scientific Reforestation

Stephen E. McDonald, research forester, Timber Management Research Staff, Forest Service.

The term, reforestation, includes both tree planting or seeding and natural establishment of seedlings from wild seeds or sprouts coming from other trees. In the near future, both artificial and natural reforestation will take place with a much greater degree of precision and reliability than has been possible in the past. In addition, the trees that do become established will exhibit higher survival rates and grow faster than now.

Both forest industry and Federal agencies are putting considerable research emphasis on more reliable, precise reforestation for the simple reason that the cost of reforestation is rising rapidly. Not only are labor, machines, and tree seed and seedling costs going up steeply, but the cost of borrowing money also has risen sharply in recent years. The need is great to accomplish reforestation inexpensively, quickly, and reliably, and to assure that trees grow rapidly following establishment.

Reforestation Today

In the United States, pioneering research on reforestation began in the 1920's with U.S. scientists adapting and refining German reforestation practices. The body of information that constitutes U.S. reforestation Practice at the present time is based on important research advances from the 1930's and 1940's. Today's methods, conscientiously applied following time-tested rules, will almost guarantee successful plantations of trees under average conditions. But even when these rules are followed to the letter, often disturbing and costly vacations in reforestation success occur.

Reforestation in the 21st Century

In contrast, consistently reliable establishment of fast-growing plantations at a reasonable cost will characterize reforestation in the 21st Century. Reforestation wino longer Follow rules for average sites extrapolated from controlled studies and repeated experience. Each reforestation project will be designed to ensure success. This design will be based on detailed physiological, ecological, and meteorological knowledge about a specific planting site and the specific seedlings to be planted.

This informed, detailed, site-specific approach to each reforestation project will be feasible because of rapid advances in several scientific fields.

Improved Methods of Measurement and Data Analysis. First, improved methods of measurement together with modern data storage, manipulation, and interpretation are revolutionizing our ability to relate causes to effects. Forest scientists can measure some things more accurately, and can quantify others for the first time. These measurements are pooled for computer analysis that allows comparisons of different variables or combinations of variables in ways impossible in the past. These advances mean that soon foresters will be able to define in detail the reasons for plantation successes or failures. As their data bases accumulate information and their experience grows, they will be able to predict accurately what needs to be done in each reforestation project to assure a high probability of success, even when conditions deviate from the norm.

Knowledge of Plant Physiology. Second, we are now in a period of revolutionary advances in the biological sciences. New breakthroughs in our knowledge of plant physiology (function) are part of this revolution. Dr. Cleon Ross, Colorado State University, has estimated that the present "half-life" of plant physiology knowledge is only about 3 years. As part of this phenomenon, more complete understanding of many aspects of plant physiology applicable to forestry and forest regeneration is rapidly evolving. An example is the potential application of the new biotechnology to forestry discussed earlier in this chapter. Increased understanding of tree stress physiology, mycorrhizal relationships, and interplant competition holds great promise of rapid technical advancement in reforestation in the near future.

Knowledge of Environment and Ecology. Finally, researchers are learning much about the interaction between seedlings and the site they inhabit. Site conditions are being measured and characterized in ways and with a precision impossible only a few years ago. Site-condition variation at both the microclimatic and macro-climatic levels can increasingly be analyzed and predicted. New climatological models can characterize forest sites on an acre-by-acre basis. Seedling source and morphology are, increasingly, being selected to precisely accommodate the environment at the planting site.

New Scientific Era

When all three of these avenues of' advancement in reforestation research improved methods of measurement and data analysis, plant physiological knowledge, and environmental-ecological knowledge are brought together, we will have entered a new era in reforestation. It will be characterized by insights into the complex interrelationships between environment, seedling condition, and seedling genetics that are the keys to a regeneration process to provide the highest probability of reforestation success and rapid tree growth. Currently, the system requires artistic application of rules of thumb to specific situations. In the future, we will apply specific, scientific prescriptions to specific environmental situations. The present art will transform into science, with excellent results produced time after time by precisely adjusting our techniques to each given planting site, year, and seed and seedling crop.

Integrating Advances into Present System. Achieving scientific reforestation is within our grasp with present technology. Learning to use this technology properly, accumulate the data, and interpret it will take time and research. It is worth remembering, however, that a tried and true system is in operation now. Over 1.8 billion trees were planted in the United States in 1985. The task is not only to do the research needed to develop the new technologies for reforestation improvement in the future, but also to meld these advances into the immense system already in operation.

Costs of Change. Changing to a scientific reforestation process will be gradual. It will also be expensive, but this does not mean the effort will not be cost affective. Right now, each year, millions of planted tree seedlings die after planting, thousands of acres of careful site preparation are lost, many trees that do survive grow poorly, thousands of acres of plantations ~here trees did not survive have to be replanted. All these shortcomings in the present system are enormously costly and occur on all forest lands, without regard to ownership. Even the most rudimentary calculations show that an increase in survival rates of just 1 or 2 percent will justify a considerable research effort. Also, the costs of effective reforestation research are quickly recouped because the benefits are realized immediately.

Resistance to Change. Another barrier to the implementation of scientific reforestation is resistance to change. It is likely, however, that the driving forces for more efficient, effective reforestation described earlier will overcome such resistance as the benefits of new procedures become obvious.

Benefits of Change. Our collective stake in scientific reforestation is enormous. Our country is presently the largest importer of wood in the world. This is a completely unnecessary drain on our economy. The United States is easily capable of growing all the wood it will ever need if cutover lands are promptly reforested, if idle lands are reforested, and if the resultant young stands are properly managed. It has only to grasp the new technological tools at hand and have the discipline and will to change to become fully self-sufficient in forest products in the 21st century.