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The severity and extent of browsing damage to pine and eucalypt plantations and possible solutions are examined. Twenty-six percent of all trees surviving 9 months after planting were browsed yet only six percent had more than 50% of foliage damaged. The most common form of damage was for the foliage to be browsed or the tree bitten off with browsing damage implicated in the mortality of the 24% of trees that died. No difference in the extent of damage between Pinus radiata and eucalypts was detected. Slight differences between three Eucalypt species and two ages of seedlings were detected; however, these differences in damage levels were insufficient to afford adequate protection through appropriate selection of species and type of nursery stock. Most of the damage was attributed to the Swamp Wallaby (Wallabia bicolor) and the European rabbit (Oryctolagus cuniculus). The use of electric or rotonet fencing and repellents containing chili or dog-urine extracts seem to offer the only nondestructive ways of minimising browsing damage. The development of less palatable species and types of nursery stock is dependent on other considerations including general suitability, but warrants further research.

The Formosan red-bellied tree squirrel (Callosciurus erythraeus) is a pest animal that causes serious damage to many conifer plantations in Taiwan. Poisoning has been the major means to control the damage. The feasibility of forestry control through habitat manipulation has been evaluated during the past 5 years. The objective of this study was to investigate the effects of forest-tending operations on the activity and damage by squirrels. Forest-tending conducted included weeding and thinning. Test sites were at three Japanese cedar (Cryptomeria japonica) plantations located in Chitou. The results of this study revealed that squirrel activity in the treated plots was greatly reduced. It was found that new damage done by the squirrels in treated areas was also reduced. This was particularly significant during an abnormal weather period when there was a continual rainstorm lasting for about 3 months. The treatments of weeding and thinning showed more significant effects on the reduction of squirrel activity than the reduction in the occurrence of new damages.