A product of the USDA Forest Service, Pacific Northwest Research Station
SVS distribution home page
|The Stand Visualization System (SVS) generates
graphic images depicting stand conditions represented by a list of individual
stand components, e.g., trees, shrubs, and down material using detailed
geometric models of individual trees and other stand components.
The images produced by SVS, while abstract, provide a readily understood
representation of stand conditions and help communicate silvicultural treatments
and forest management alternatives to a variety of audiences. SVS
provides the following capabilities:
A data conversion program, FVS2SVS, links SVS to the Forest Vegetation Simulator (FVS) to provide stand growth modeling and visualization capabilities for most geographic regions in the U.S.
The SVS software is currently used by a wide variety of users in federal agencies within the U.S., private industry, academia, and research organizations.
Data RequirementsSVS requires two primary types of data: a list of stand components and plant form definitions. The stand component list describes the species, size and location of each component in a stand. Plant form definitions describe the appearance of each species and, optionally, the appearance of individuals exhibiting different growth forms within a species.
The following parameters describe each stand component:
The simplest input suitable for use in SVS consists of a simple stand table describing the species, dbh, height, crown ratio, and density of trees in a stand. The included TBL2SVS utility, converts such stand table input into a list of individual components.
Plant Form DefinitionsUsers define the appearance of each species represented in a component list using a plant form definition. Form definitions describe the overall growth form; geometry and number of branches or leaves; and color of the stem, branches and foliage. SVS provides a "tree designer" to help users develop form definitions for the species and growth forms in their area. SVS uses the species identifier as the primary link between the component list and the plant form definitions. However, two additional parameters, tree class and crown class, can be used to distinguish individuals within a species. Interpretation and use of these two parameters is under the complete control of the user. SVS reserves the value of 99 for the tree class and crown class to represent a "wild-card" value.
Designing Silvicultural Treatments with SVSSVS allows users to create stand treatments by marking individual trees or groups of trees on either the perspective or overhead displays. Marking rules can be used to select trees based on their attributes. The marking dialog lets users develop silvicultural prescriptions by specifying the desired characteristics for the residual stand.
Computer System RequirementsSVS is designed for personal computers running Windows 9X, 2000, XP and NT (version 3.51+). There is a DOS version of SVS available but it is no longer supported.
This page was last updated on September 27, 2001 by Diane Smith