and a grizzly bear and her cub chased us off.  突然一头灰熊和她的熊宝宝出现，把我们赶跑了。

And I had no bear spray. But you know, this is how forest research in Canada goes. 然后我还没带防熊喷雾剂。但你知道吗，在加拿大做森林研究其实就是这样的。

So I came back the next day, and mama grizzly and her cub were gone. 所以第二天我又回来了，灰熊妈妈和熊宝宝没在。

So this time, we really got started, and I pulled on my white paper suit, 这一次我们可以真正开始实验了，我穿上我的白纸套装工作服，

I put on my respirator, and then I put the plastic bags over my trees. 带上呼吸器，然后给我的树都罩上了塑料袋。

I got my giant syringes, and I injected the bags with my tracer isotope carbon dioxide gases, first the birch. 我拿出我那些大注射器，往袋子里面注入了含有示踪同位素的二氧化碳气体，首先是纸皮桦。

I injected carbon-14, the radioactive gas, into the bag of birch. 我往罩纸皮桦的袋子里面打入了有放射性碳14的气体。

And then for fir, I injected the stable isotope carbon-13 carbon dioxide gas. 然后是花旗松，我往他们的袋子中注射了含有稳定性同位素碳13的二氧化碳。

I used two isotopes, because I was wondering whether there was two-way communication going on between these species. 我用了两种同位素，因为我不知道这两种树之间的交流是否是双向的。

I got to the final bag, the 80th replicate, and all of a sudden mama grizzly showed up again. 当我走向最后一个袋子时，也就是第80棵样本，突然间那头灰熊妈妈又出现了。

And she started to chase me, and I had my syringes above my head, 然后她开始追我，我把我们的那些注射器举过头顶，

and I was swatting the mosquitos, and I jumped into the truck,  扑打着周围无数的蚊子，然后跳上了卡车，

and I thought, "This is why people do lab studies." 然后我想，“这就是为什么人们喜欢在实验室做实验的原因吧。”

I waited an hour. I figured it would take this long for the trees to suck up the CO2 through photosynthesis, 我等了一小时。我觉得这个时间差不多可以让那些树通过光合作用吸收二氧化碳，

turn it into sugars, send it down into their roots,  转换生成糖，再把糖送到它们的根，

and maybe, I hypothesized, shuttle that carbon belowground to their neighbors. 然后也许，我也是猜测，把那些碳元素从地下传给它们的邻居。