... of trees normal growth, it can identify trees growth rate, age of the trees, trees growth hardness degree and nutrients migration. ... center, make a reverse rotation, and get wood core within core extractor. Tree growth condition can be analysed by ... distribution.CompositionSleeve, awl and a core extractorModelWood core extractor: d=5mmDrill pipe length: 20cm, 25cm, 30cm, 35cm, 40cm Plant Growth Awl