GB 6000-1999Tree seedling quality grading of major species for afforestation (English PDF)

3 Grading requirements

4 Test methods

5 Inspection rules

Foreword

This standard is a revision of GB 6000-1985, Seedlings of major tree species for afforestation, made to keep pace with the development of seedling production technology in China. The revised standard retains those contents of the original standard that practice has shown to be suited to seedling production and afforestation in China, and makes the following changes to the relevant contents of the original standard:

- 19 tree species have been added and 11 removed, and certain quality indicators not suited to current production have been appropriately modified;

- root system length and the number of first-degree lateral roots longer than 5 cm, or the root width, have been added as indicators for seedling quality grading;

- Grade III seedlings (unacceptable seedlings) are no longer listed among the seedling quality grades; a two-grade system is used instead, and only the grades of Grade I and Grade II seedlings (acceptable seedlings) are specified;

- other important morphological and physiological indicators affecting seedling quality have been added as comprehensive control conditions;

- the indicator of the total number of new roots (TNR) of seedlings has been added, to test the vigour of conifer seedlings lifted from the nursery after long-term storage;

- the indicators of seedling output per unit area and density have been removed.

From the date of its implementation, this standard replaces GB 6000-1985.

Annex A of this standard is a normative annex.

This standard was proposed by the State Forestry Administration.

This standard is under the jurisdiction of the National Technical Committee for Standardization of Forest Tree Seeds.

Drafting organisations of this standard: Beijing Forestry University, Heilongjiang Academy of Forestry Sciences, Nanjing Forestry University, Guangxi Academy of Forestry Sciences, Sichuan Provincial Forestry Department, Three-North Bureau of the State Forestry Administration, General Station of Forest Seed and Nursery of the State Forestry Administration.

Participating drafting organisations: Seed and Seedling Station of the Beijing Municipal Forestry Bureau; Seed and Seedling Stations of the Forestry Departments of Liaoning, Shandong, Shanxi, Gansu, Inner Mongolia, Hunan, Fujian, the Guangxi Zhuang Autonomous Region and Zhejiang; Yunnan Provincial Forest Tree Seed and Seedling Station; Afforestation Bureau of the Daxing'anling Forestry Company.

Main drafters of this standard: Song Tingmao, Liu Yong, Jin Tieshan, Yu Yuankun, Miao Meiqin, Feng Debin, Wang Xiuqin, Li Changfa, Zhou Jingli.

Approved by the State Bureau of Quality and Technical Supervision on 1999-11-10; implemented on 2000-04-01.