最近发现北美的烟树 , 原来就是中国的黄栌。　据说香山的多数黄叶／红叶都是这个树引起的。

原来那些看起来像“烟”的东西，　既不是花，　也不是种子。　而是支持果实的枝子。　所以我叫它们果枝。　

我怀疑这个是Cotinus coggygria，　因为密歇根好像只有一个种。　另外一种叶子是红色的，　好像应该是同一个种的变种？

我去年才知道这些花是Cotinus， 以前只看到蜜蜂去采， 也没有拍照。 去年6.3.号拍到这些照片， 今年现在已经开花了。

Smoke bush (smoke tree, Cotinus coggygria, Anacardiaceae) is in the sumac family. It is called "smoky bush" because the long stalk-like structure supporting the seeds (most stalks are empty with a few seeds here and there), in yellow or pick color, gives a smoke like appearance when viewed afar.

I have seen bees visiting this plant in front another botanic garden but then I saw a large patch of it near the MSU bee biology building.  Last year it was blooming June 2 and I took some photos with my cell phone and next day I went back and took more with my D700.  This year they are blooming again now.  Honey bees seem to love this plant. I assume it provides both nectar and pollen.  Bees do not stay very long (1-2 seconds) per flower so I did not have super close photos (unlike the autumn olive ones, bees stay for longer than 3 seconds, so it was quite easy to get them).

This tree turns colors in the fall, yielding yellow or red leaves. Hence the Chinese name for it is 黄栌 (yellow haze).

1. Flowers only

2. A honey bee in flight.

3. This bee landed

4. Now we can see the pollen on the pollen baskets clearly.

5. A honey bee hanging upside down, clearly probing for nectar.

6. A very small bee, perhaps a halictid?

7. A damsel fly also on the flowers. Therefore, anytime you plant good nectar plants for honey bees, you will be also helping other insects, who also exploit flowers for pollen (many solitary bees) and nectar (e.g. damselflies or butterflies).

参考文献：

1. http://en.wikipedia.org/wiki/Cotinus_coggygria