牛樟扡扦插苗造林五年後之生長表現

Growth Performance of 5-yr-old Cinnamomum kanehirae Rooted Cuttings after Planting

高毓斌(Yu-Ping Kao) ； 黃松根(Son-Gen Huang) ； 劉一新(I-Hsin Liu)

《台灣林業科學》 14卷1期 (1999/03) Pp. 45-52

https://doi.org/10.7075/TJFS.199903.0045

摘要

採自關山林區天然林中牛樟根株之萌蘗所育成之20個營養系，於六龜分所多納林區造林5年後，無論是胸徑、樹高或成活率在營養系間之差異均呈顯著，平均成活率僅及55%，惟若慎選其中表現較優之9個營養系，成活率約可提昇至67%，且平均胸徑與樹高各可達7.9cm及4.9m。牛樟造林成活率較低，部份係因造林後第l年內之生長相當緩慢。屆滿1年生之苗高平均僅為54cm，極易遭受雜草凌壓，惟第2及3-5年間之平均年生長可達66cm及100-110cm，此仍視營養系而異。表現優良之營養系生長較佳，且能承受乾燥之冬季及雨季之雜草競爭；表現低劣之營養系，無論是乾、雨季之枯死率均偏高。以20個營養系5年生之成活率而言，與l、2及4年生之樹高均具極顯著相關，尤以2年生之樹高為然，故牛樟扡插苗造林成活率之提昇，應以促進造林初期之高生長為優先。

關鍵字

牛樟 ； 營養系比較 ； 生長表現

並列摘要

Shoot cuttings were asexually propagated from stump sprouts of 20 individuals of Cinnamomum kanehirae in natural forest in the Guanshan area; 1.5 yrs after rooting, the rooted cuttings were planted at the Duona District of the Liukuei Station, TFRI. After 5 yrs, significant differences were shown in DBH, tree height, and survival rate among the 20 clones evaluated in this study. Average survival rates for the 20 clones were poor, with only 55% surviving at 5 yr old. But, 67% of cuttings survived for the top 9 clones which showed superior height and diameter growth. The lower survivability correlated with the height growth pattern during the first 2 yr after planting. According to the results, height growth only reached 54cm at the end of the 1st year. Most individuals of the slow-growing clones were therefore easily suppressed by weeds. Annual increments of height growth increased substantially to 66 and 100-110cm for years 2 and 3-5, respectively, yet differences among clones were still apparent. Clones with better height growth expressed higher resistance to dry stress in winter and better competition with weeds during the wet season. On the contrary, the inferior clones with plagiotropic growth sustained higher mortality rates both in winter and rainy seasons. The survival rate at 5 yr old for the 20 clones tested was highly correlated with tree height in the 1st, 2nd, or 4th year of growth. Accordingly, higher survival rates could be achieved if early height growth was accelerated by proper silvicultural practices.

並列關鍵字

Cinnamomum kanehirae ； clone comparison ； growth performance