Comparative Studies Of Growth And Economic Benefit In Three Clones Of Eucalyptus

The research plot was located in the afforestation base of Shangsi forest farm and the study objects were Eucalyptus stands from the same site condition and management. The differences of preserving rate,tree height,chest height diameter and stand volume of the three clones of Eucalyptus stands of sprouting regeneration and stock planting were analyses.The profits were compared after 4 years, and the main results showed that:(1)The preserving rates of every year in the 4 years showed no significant differences(p>0.05) of both stock planting and sprouting regeneration stands.(2)The differences of the tree height and the chest height diameter between "Guang No.9" and "DH32-28" Clone of Eucalyptus by stock planting were remarkable and extremely remarkable, respectively. But the differences of the chest height diameter between "Guang No.9" and "DH32-29" Clone were not significant. The stand volume of "DH32-29"Clone had no significant difference between "DH32-28" and "Guang No.9" Clone.(3)In the sprouting regeneration stands,the tree heights and stand volume of "Guang No.9" and "DH32-28" Clone of the last three years both showed significant differences and showed significant differences of chest height diameters in the last two years.(4)The tree heights of sprouting regeneration stands were basically higher than the stock planting’s and there was a difference of about 1 cm of the chest height diameter between the two management mode during the growth range.The differences of stand volume of the two management mode were great that were 1.189m3/mu (2-years-old),2.382m3/mu (3-years-old) and 2.444m3/mu (4-years-old),respectively.(5)The profits differences of sprouting regeneration and stock planting stands were 853.20 yuan(Guang No.9)、1170.03 yuan(DH32-28) and 986.29 yuan(DH32-29),respectively,ratio was 1.43 to 1.49 to 1.48.