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1·The result of investigation indicated that Pinus ponderosa has been introduced successfully with a promising features alien conifer. Its introduction could be extended in large.

调查结果表明，美国黄松已在黄土高原引种成功，是一种很有前途的国外针叶树，可以扩大引种，繁殖推广。

2·On the basis of recounting details of Pinus ponderosa in the world and domestic, its prominent characteristics of growth in Yanan arboretum on the loess plateau has been emphasized on the paper.

在阐述了世界和我国引种栽培美国黄松的基础上，着重阐述了黄土高原延安树木园引种栽培生长的突出表现。