科	毛茛科Renunculaceae
属	菟葵属 Eranthis
种	冬菟葵 E. hyemalis
俗名	菟葵
ZBAS*:	8

Winter aconite (Eranthis hyemalis) belongs to Ranunculaceae. Its common name in English (winter aconite) comes from its flowering time (winter), and aconite may refer to poison, which is similar to real aconitum (Aconitum). The genus name is Eranthis, Its meaning in Greek is spring + flower (Er + anthis). The species name means winter blooming. Aconitum is poisonous, and Eranthis is also poisonous. It mainly contains toadadienolide, which is a cardiac glycoside, but not as poisonous as aconitine (that is life-threatening).

I haven’t found reports that nectar or pollen is toxic to people. This flower is native to Europe and Asia, but has been “Naturalized” in North America.

There are 9 species in this genus, and it is estimated that there are at least 5 species in China.

• Eranthis albiflora. Western China
• Eranthis cilicica.Southwest Asia
• Eranthis hyemalis. Southern Europe (now settled in North America)
• Eranthis lobulata. Western China
• Eranthis longistipitata. Central Asia.
• Eranthis pinnatifida. Japan.
• Eranthis sibirica. North Asia.
• Eranthis stellata. East Asia (North China, South Korea, Southeast Russia).
• Eranthis byunsanensis. South Korea

When the weather is warm enough, I often see bees picking this flower in Michigan. This flower will bloom before the crocus. So it should be one of the earliest flowers in Michigan. Both flowers will bloom before maple and willow.

After a long winter, bees are eager to forage on these early flowers. Because the bee pollen basket contains pollen, of course it is known that this flower provides pollen. Then based on the bee collecting behavior on the flower, it is judged that it also has nectar.

A recent study (Rysiak and Zuraw, 2011) indicates that the nectar concentration of this flower is very high (61-78%, with an average of 72%), but the total weight of nectar is only 1.23 mg per flower, so the average per flower has only 0.88mg sugar. I have previously determined that a bee needs to consume 11 milligrams of sugar every 24 hours to survive, so worker bees need to visit many flowers. Honeybee sacs can carry up to 50 microliters of liquid, but the average is only 25 milligrams.

1. I Photographed a flower without bees to show the complete structure of the flower. The yellow tubes are petals and their bases are nectaries. And now the petal-like structure is actually a sepal!

2. The phote was taken on March 21, 2014. It was too cold that day and there are no bees.

3. The photo was taken on March 31, 2014, that day I took students to take pictures of the flowers outside. I taught “insect macro photography” at that time. Nikon D700.

4. The photo was photographed on March 17, 2010. The flower bloom earlier that year.

5. The bee is obviously looking for nectar, but she also has pollen on her legs.

6. The green structure in the middle should be pistil.

7. Golden fields! (Fields of Gold!). Of course, this is not barley.

8. The photo was taken at 2007.3.13, It is earlier.

9. The following is not a honeybee, It is a solitary bee.

10. Ants also come to explore for nectar.

11. This photo is taken at 2002.3.6. It is flowering earlier. Then it snowed again. I remember the earliest flowering around February 6th, but I can’t find the photo. (Coolpix 990, 3.2 megapixels).

12. The oldest photo is photographed on 2000.3.8, Olympus D450Z (1.3 megapixels! My first digital camera, cost $ 500 in 1999)

13. Lastly, what does a sunflower look like under ultraviolet (UV)? On the left is an image of visible light (Nikon D70. Even if it has not been modified, because the filter inside is weak, the Nikon D70 has a certain sensitivity to ultraviolet light. All cameras except D70 and D40 must remove the filter in front of the CCD. Mirror so that it can receive enough UV rays. In addition, a special lens is needed to allow enough UV rays to pass through-most modern lenses have a UV-resistant coating. On the right I use D70, plus a special one that blocks visible light and infrared rays but passes UV rays. Filters, obtained photos. Note that the center of the pollen is black under UV. In addition, the back of the petals is also black with only a circle of yellow. And what we see (left), the front and back are the same yellow What bees see is a superposition of the two (because they can see visible light other than red, in addition to ultraviolet light).

Here，the flower bloomed late this year. It is estimated that these days should be flowering. The last time I visited the Botanical Garden (March 20), it was almost blooming. But some flowers were frozen. Occasionally several calendula bloom at the same time. But I didn’t see it last time. Another Lycoris radiata is also being opened, and that bee collects less.