Framework / Assessment California Forests and Rangelands: Proposed Indicators Summary Characterize the general management approach of timberland owners and quantify the extent to which that approach is applied. There are six landowner groups in California each of which has a different approach to timberland management. These include forest industry, forest industry suppliers, custodial owners, land trusts and conservation organizations, tribes and public agencies. Each of these groups varies in its adoption of sustainable forestry practices.