In all the pines a very thin membrane, in appearance much like an insect’s wing, grows over and around the seed,

松树种子通常长有一层薄膜，形状酷似昆虫翅膀，独立的薄膜裹住并庇护种子生长，

and independent of it, while the latter is being developed within its base.

使种子得以在根基部孕育；

In other words, a beautiful thin sack is woven around the seed, with a handle to it such as the wind can take hold of,

换句话说，就像把种子裹护在漂亮细薄的网袋里，让风擎住从网袋里长出的一个小小把手，把种子命运交与风来主宰。

and it is then committed to the wind, expressly that it may transport the seed and extend the range of the species;

未来的风儿就可裹带种子翱翔，为植物种群繁衍开拓疆土。

and this it does as effectually as when seeds are sent by mail, in a different kind of sack, from the patent office.

与专利局袋装邮寄包裹相比，种子职能卓有成效，毫不逊色。

There is, then, no necessity for supposing that the pines have sprung up from nothing,

由此看来，人们完全毫无必要认定，松树凭空便可萌发成林；

and I am aware that I am not at all peculiar in asserting that they come from seeds,

我相信，树木乃种子孕育而生，这一观点，绝非只是为我个人的玄思冥想，

though the mode of their propagation by Nature has been but little attended to.

当然，大自然传播繁衍种子的方式向来鲜人关注。

They are very extensively raised from the seed in Europe, and are beginning to be here.

北美大多树种来自欧洲，并逐渐开始在此繁衍生息。

When you cut down an oak wood, a pine wood will not at once spring up there

当你砍斫一片橡树林，北美油松林几乎不可能很快继之而起，

unless there are, or have been quite recently, seed-bearing pines near enough for the seeds to be blown from them.

除非原先就已成林，或已具相当规模，并且砍伐地带不远处还应长有结籽的松树，种子才有可能吹来萌发。

But, adjacent to a forest of pines, if you prevent other crops from growing there,

不过，就松林周边而言，万一土壤适宜，

you will surely have an extension of your pine forest, provided the soil is suitable.

同时确保其他作物无法生长，你也势必将会拥有一片扩展的松林。