There is a limited supply of timber available for any consumer. If 100 consumers each want one board of wood and only 90 are available, a method for deciding which consumers will not receive the boards must be decided. One way of deciding is that the last 10 persons who try to get a board will lose out. Usually however, some individual, or series of individuals, has cultivated the land, planted, tended, cut down the trees, made the boards and brought them to market. They are owned because labour has been added to the trees and made them available to the consumer. The seller may decide to use a different method and ask that each buyer, exchange something for a board. The price of the exchange will vary depending on the demand for, and supply of, boards. Some people will have to forego a board because they are unwilling or unable to pay the price. They will have to make do with an alternative or do without. For trade to occur, each individual must produce something, to be offered in exchange for the board. People who fail to produce anything, or who produce worthless goods, will be unable to exchange with others and will become impoverished until they adjust their production. The owner of the forest will manage it to try to get the greatest possible value from the land. He will probably not cut down all the trees in one year and then have no income for the next few decades while the trees grow again. He will decide how much to produce each year and then plant more trees, so that his land will continue to produce timber indefinitely. His land is a capital asset and has a value of its own. This value is often dependent on the value of the trees it is capable of producing. If the demand for timber rises, he may fell more trees. But he may risk reducing the productivity (and thus the future value) of his forest if he does this. The key variables involved in his decision are the present and expected future value of the forest and the timber. If a forest is not owned and anyone is permitted to cut the trees, then no future value will be attached to the forest and it will be destroyed in short order. If the forest is owned, then the owner will attempt to maintain the productivity and value of the forest by restricting the sale of wood from the forest. Consumers may complain that wood is scarce and thus the price high, but another competitor is welcome to enter the market and supply cheaper wood. The key to conservation and production are incentives. If there is an incentive to produce more, then Acting Man will tend to do this. If there is an incentive to conserve a resource, then he will tend to do that. A resource can easily be conserved if its future value is expected to be high or if the cost of its destruction becomes prohibitive. Owners of resources will gain if they preserve the valuable resource. Acting Man will look for alternatives if a resource becomes prohibitively expensive. A resource will be expensive if it is scarce and if demand is high. In this case, there will be a tremendous incentive to find alternatives to it. The original resource will tend to be conserved.