[Table of Contents]
6. STOCKING STANDARDS
ALASKA
Minimum stocking standards are given in the Regulations for the purpose of deciding if reforestation is required. For Region I, 50% of the original stand basal area or a minimum of 160 vigorous saplings or merchantable trees of commercial species per acre (about 400 trees per ha) constitutes adequate stocking. For Regions II and III, the minimum number of trees per acre varies form 120 to 200 (about 300 to 500 trees per ha).
For reforested areas, a minimum of 200 healthy seedlings per acre (about 500 trees per ha) are required in Region I. For Regions II and III, 450 seedlings per acre (about 1,000 trees per ha) are required.
BRITISH COLUMBIA
Stocking standards are the required number of healthy, well-spaced, acceptable trees. In British Columbia, stocking standards or partial cutting stand management objectives must be designed and managed to meet integrated resource management objectives. Under a Silviculture Prescription the establishment and maintenance of a minimum number of healthy well-spaced trees of the preferred and acceptable species must occur. No actual stocking levels are specified in the Act or Regulations. Those kind of details are addressed in various guidebooks.
CALIFORNIA
Stocking standards and methods of determining stocking are presented in Subchapter 7, Article 5 of the Rules. Within 5 years of completion of logging, a Report Of Stocking must be submitted to CDF. Under Subchapters 4,5, & 6, Article 3 of the Rules, when artificial regeneration is proposed, an annual report of stocking must be filed commencing 2 years after the completion of logging.
FINLAND
Stocking standards are not specified in Finland's forestry legislation. However a recommendation of the National Forestry Centre states, "... leave an adequate number of vigorous trees of good quality and of appropriate species to populate the site so that maximum use is made of the soil productivity" (National Extension Service Forestry Guidelines).
GERMANY
Federal Republic of Germany
The Federal Forest Law does not regulate forest operation activities.
Baden-Wurttemberg
Stocking standards are not specified in the Forest Law. Historic standards resulted in forest land overstocked with exotic tree species. The overstocked forest land produced unhealthy stands that were susceptible to blow-down during storms (Brunner, pers. comm.). Today, the forest administration is encouraging forest owners to re-establish native species. Subsidies are available for re-establishing forests that include broadleaf species.
Bavaria
As in Baden-Wurttemberg, Bavaria does not include stocking standards in their Forest Law. However, standards are specified for state and community forests in the silvicultural plans prepared by the Forest Offices. Subsidies are used to regulate stocking in private forests.
Mixed species forests are also promoted by Bavaria's forestry administration. On average, approximately 10 million deciduous trees are planted annually. This represents roughly 70% of all annually planted stock (Bavarian Ministry of Food, Agriculture, and Forestry, 1989).
NOVA SCOTIA
Plantation assessments are conducted in the fall of the second year after establishment to determine survival and growth rates and corrective action needed to achieve desired levels (M.O.P.S., 1994, Appendix J:1). Subsequent assessments must be done 5 years after establishment, and at 5 year intervals until such time as the plantation is successfully established and has reached the free to grow stage (M.O.P.S., 1994, Appendix J:1).
ONTARIO
Minimum and desired stocking standards are detailed in Silvicultural Guides for the three main forest types in Ontario. The time limit within which stocking standards must be reached is currently not specified. However, stocking surveys have usually been carried out at the 5-7 year stage (Environmental Assessment Board Decision - EA -87-02). Forest Management Agreement holders have been required to re-treat the area at their own expense if it does not meet the desired stocking level by the fifth year.
The Free Growing Regeneration Assessment in Ontario - Draft, is a policy document which outlines an assessment methodology for determining the free-growing status of areas harvested under even-aged systems in Ontario. This document states that the minimum and maximum number of growing seasons since disturbance in which this survey must be conducted must be determined locally. Based on recent data this document suggests that the recommended window for this assessment is 7 to 11 years (van Kerkhof, pers. comm.).
OREGON
Minimum stocking for clearcuts is defined in the Act at 200 acceptable trees per acre (500/ha). More specific details are given, by administrative region, in the Rules. They vary according to region, site class and tree size.
SWEDEN
Stocking standards, although not specified in the Forestry Act, are outlined at the national level. Sweden's stocking standards refer to the number of stems per hectare required in a cut over area at a specified time after harvest. The number of stems varies with species and site conditions and the specified time varies with regeneration method. In general, required stems per hectare vary from 1,000 to 2,300 (P. Kjellin, pers. comm.).
Compliance to the stocking standards are monitored by the County Forestry Boards. The County Boards conduct surveys that are then summarized by the National Forestry Board. Additional surveys are done by the National Forest Inventory and by large forest companies. Approximately, 80% of the reforested areas meet the stocking requirements. This includes 70% of naturally regenerated areas and 85% of planted areas (P. Kjellin, pers. comm.).
In addition, seeds, seedling transplants, and other forms of regenerative material intended for the establishment of new forest stands are regulated ( Section 7, Forestry Act).
TASMANIA
Establishment and maintenance treatments that are most likely to achieve full restocking must be used. In clearcut or slashburn areas, regeneration standards must be achieved within 2 years after harvest, and a regeneration survey should be done within these 2 years. The required stocking standard in a shelterwood system must be achieved within 3 years. Even-aged growth standards should be met on completion of logging, and if standards are not met, further regeneration treatment should be conducted within 3 years using the multi-aged stocking standard. Multi-age stocking standards must be achieved within three years after operations. Plantations should aim for 90 percent of stocking standard for the chosen management system, and if survival is less than 50 percent, re-establishment should follow, providing the reason for initial failure is identified and corrective measures can be taken. The forest owner should periodically check forest health and regeneration for at least 10 years, and rehabilitate if necessary. Appropriate measures must be taken to protect seedlings from grazing and browsing (FPC, 1993:75-76).
UNITED KINGDOM
It is a condition of felling that an area will be restocked. Stocking at a level of at least 80% of the agreed density must be achieved within 5 years of the first claim for restocking grant. The newly restocked site must be maintained for at least 5 years, and management grants are available to assist with further management work.
U.S. FOREST SERVICE (REGION 6)
Stocking standards are established by policy (Regional Guides) and implemented through contract clauses. Standards vary according to regional and site specific conditions. Standards for the purpose of defining clearcut areas are noted in Part II, Section 3 of this report.
VICTORIA STATE
On both public and private lands, stocking assessments must be completed within two years after regeneration establishment in order to monitor success. If stocking standards are deficient, further assessments must occur as prescribed in Forest Management Plans or Planning Schemes. If stocking still fails to meet standards as prescribed by the Department of Conservation and Natural Resources at the end of the prescribed regeneration period, (on both private and public lands) additional silvicultural work must occur to ensure satisfactory stocking (Code, 1989:9, 31).
WASHINGTON
Standards are defined in the Rules and they differ for eastern and western Washington. Acceptable stocking must be established usually within 3 years of completion of harvesting for western Washington and 5 years for eastern Washington. The Department of Natural Resources may determine an acceptable period of between 1 and 10 years for natural regeneration.
WESTERN AUSTRALIA
Stocking standards are referred to in Silvicultural Specifications. Jarrah forests are harvested using different silvicultural methods depending on the status of the stand prior to commencement. In a natural regrowth stand, thinning will occur, and the rule of thumb is that a minimum of 15 sq m/ha basal area of crop trees must be maintained. A gap will not be created within the jarrah forest unless there is either (i) > 1000 stems/ha of ground coppice or advanced growth or (ii) > 500 stems/ha of saplings. The minimum stocking standard for clearfelled Karri forest is 1666 stems per hectare, including hand-planted seedlings and natural regeneration. In the autumn following the previous winter's planting, a survival survey is conducted, and survival must be approximately 90% or replanting must occur. In softwood forests, the contractor is responsible for establishing the second rotation until age 3 (Clarke, pers. comm.).
