Regional site index curves for nationwide private and public Sugi (Cryptomeria japonica) forests to develop yield tables

Key Points

• The aim is to create regional site index curves for Sugi forests to assist in yield prediction.
• Analyzed data from 5,730 survey points across private Sugi forests aged 1 to 100 years.
• Compared 13 growth functions to establish appropriate site index curves.
• Developed curves for 7 geographical regions and a common national curve.
• Identified 6 suitable growth functions including Chapman-Richards and Korf for different growth evaluations.
• Curves can be combined with density management diagrams for yield predictions based on various planting and thinning scenarios.

Abstract