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Uneven-aged forest management is acquiring increasing importance throughout the world as an alternative to clear cutting. Simple stage-structured matrix models can be used to predict the growth of uneven-aged stands, and they are easily incorporated in optimization analysis. Parameters of these models can be estimated from readily available permanent plot data. Such a growth and yield model is presented for mixed, uneven-aged Douglas-fir and hardwood stands. The model was calibrated with data from 66 permanent plots in Oregon and Washington. The density-dependent matrix model predicts the number of trees by diameter class and species type, softwood or hardwood. The parameters are based on individual tree growth equations, individual tree mortality equations, and stand ingrowth equations. The individual tree equations are a function of tree diameter, stand density, species, and site index. The stand-level ingrowth equations are a function of stand density. The model was validated in the short term by comparing the number of trees in each diameter and species class at the time of the second inventory with the number predicted by the model, given conditions at the first inventory. A long-term validation of the model was also done by comparing the steady-state stand structure and stand volume with those observed for old-growth stands. The model was applied to show the effects of different cutting cycles on productivity, diversity of tree species and size, and financial returns. The results suggest that uneven-aged management of the Douglas-fir forest type in the Pacific Northwest can be as productive as even-aged management, with the added benefits of continuous cover forestry.

SouthPro is a Microsoft Excel add-in program that simulates the management, growth, and yield of uneven-aged loblolly pine stands in the Southern United States. The built-in growth model of this program was calibrated from 991 uneven-aged plots in seven states, covering most growing conditions and sites. Stands are described by the number of trees in 13 size classes for softwood, soft hardwood, and hard hardwood species. SouthPro allows managers to predict stand development, by year and for many decades, from a specific initial diameter distribution. Cutting regimes are specified by the timing and intensity of harvest. Cutting intensity can be set by a free target distribution or a basal area-maximum diameter-q-ratio (BDq) target distribution, or as a diameter-limit cut. Diameter distribution, basal area, volume, income, net present value, and stand diversity by species group and size class are shown in tabulated and graphic form.This manual provides suggestions for working with Excel, describes program installation and activation of SouthPro, and gives background information on the SouthPro growth model. The manual includes a comprehensive tutorial that explains how to start the program; enter simulation data; generate BDq distributions; add, delete, and retrieve setup files; execute single and multiple simulations; plot summary statistics; and produce stock-and-cut tables and marking guides. Limitations of the model and appropriate interpretations of its predictions are discussed.

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