Recovery Plan for the Northern Spotted Owl - DRAFT

good that is achievable at various costs. For timber, the supply curve reflectsthe real costs that would be incurred in all the activities needed to grow trees,harvest timber, and bring logs to the mills to be sawn into lumber. Such costsinclude forest management, road construction, cutting and loading, andtransportation. It also includes the cost of complying with regulations designedto reduce the environmental effects of these activities.As is the general case with supply curves, the timber supply curve slopesupward as shown in Figure H. 1. At any given time, there are numerous sitesthat could be harvested at various costs. When prices are higher, it is worthwhileincurring greater costs to harvest additional timber. The upward slopingsupply curve reflects the economic diversity of the existing forestlands. Itresults from a mixture of stands of timber, some with relatively low costs perboard foot, some with relatively high.The supply curve can be derived from a table listing the annual amount oftimber that could be harvested at each cost from each site in the inventory.The total amount that could be produced at each cost is the sum of the annualharvest at that cost from all the sites. The supply curve shows the annualproduction at each price which is the sum of the potential annual harvest at allcosts less than or equal to the price. Table H.7 provides an example of this wayof deriving a supply curve. Figure H.2 shows the supply curve derived fromTable H.7.A region's timber supply curve reflects the condition of its current inventory ofstanding timber. For example, Figure H.3 shows two supply curves, one thatwould yield very high levels of production over a broad range of timber pricesand a second that yields relatively little production at low prices, moderateproduction at midrange prices and not much increase in production even atfairly high prices. The first would characterize production from the forestlandsin a region that has a substantial inventory of mature standing timber, thesecond from a region with limited forestlands or forestlands where the lowercost timber already has been harvested./IPSci)0-D2a)C.0C.)0a1)C.)Annual rate of productionQ/oFigure H. 1. Timber supply curve.559