China has the world's most ancient tree species — metasequoia.

中国有世界最古老的树种——水杉。

《新英汉大辞典》

It looks like an ancient tree fossil.

这个好像是古树的化石。

youdao

Today, it is a very large and ancient tree.

今天，它是一个庞大而古老的树。

youdao

Slowly she began her dangerous trip down the ancient pine tree.

VOA: special.2010.04.03

There's even documentation for an ancient tree situated below the front porch.

WSJ: Hudson River Schooling

Walking through my favorite part of campus, past an ancient gnarly tree by the faculty club, I came upon three students playing frisbee.

FORBES: A Texas Transplant Returns To Berkeley

From the shadow of the garage, I beheld the back yard, with its Norwegian maples, the tilted white birches, the ancient apple tree whose branches touched the windows of the family room, and for the first time, it seemed, I understood the green glory of this acreage as something indifferent to human life and quite apart from the Victorian manse set upon it.

NEWYORKER: Wakefield