Abstract: Formation and microstructure observation of traumatic gum canals by tapping wounds in the Liquidambar formosana Hance trees grown in Guangxi, Jiangxi and Guizhou were researched. Microexamination shows: no traumatic gum canal can be found in liquidambar xylem without the trauma,but all the trees with tapping wounds formed traumatic gum canals. The results indicated that wounding is the necessary requirement for traumatic gum canals forming. In different places, the amount of the traumatic gum canals was different, and it related obviously to the yield of the resin, the more the traumatic gum canals, the higher resin yield. The distribution of the traumatic gum canals in the circumference of the trees is depend on cutting location. The number of traumatic gum canal from L.formaosana were as follows:Jiangxi 4-5 row,Guizhou 2 row, Guangxi 1 row. Distribution of traumatic gum canal after tapping in trunk circum ference are different with different notched location. Tapping wounds of 5-10 cm wide can affect the cambium within 1/4 circumference in trees, and cause its produce traumatic gum canals.

Key words: Liquidambar formosana Hance, tapping, traumatic gum canal