北部第二高速公路全線總長117公里，目前已完全通車。本研究乃針對北二高之 關新段，目前自然入侵之植物種類及人為植栽之樹種，做基本之調查。人為植栽以櫸木之株 高與樹幅明顯較其它植物為多，濕地松之活力最佳且樹型最完整。灌木以金露花的平均株高、 植株樹冠生長、活力以及樹型完整度等項目均是最高者。自然入侵之上層植被以烏臼與沙朴 最為優勢。中層植物之優勢為軟毛柿與樹杞。下層植物之優勢種為五節芒與大花咸豐草。 The second north national freeway was completed now. The goal of this research is to investigate the existing greenery species along the Kuanhsi-Hsinchu section of this freeway from the viewpoints of the growth and suitability. The results showed that Zelkova serrata are the highest and most widespread. Pinus elliottii is the most vigorous and the best form of tree. The best shrubs is Duranta repens. Upper stratification dominant plants is Sapium sebiferum and Celtis sinensis Bidens chilensis and Panicum maximum are the most dominant ground covers.
