Archives For native bees

If you happened to walk around the Heritage Garden in late June, the unusual blue color of the Moroccan mountain eryngo (pronounced eh-RING-go), Eryngium variifolium, probably caught your eye, and its peculiar perfume tickled your nose. It was also swarming with flying insects.

The odor was not lovely and sweet. I would describe it as similar to musty, molding fruit—not unpleasant, but certainly not a fragrance you would wear. It only lasted a few days, during which time it hosted an amazing number and variety of insects. I attempted to photograph and identify as many of them as I could. This was a lot harder than I expected, because the insects were in constant motion and most of them were small. I didn’t always capture the key features needed to identify them at the species level. In spite of this, you’ll see that that the variety was astounding. Let me introduce you to what I found at the Chicago Botanic Garden recently.

1. Carpenter bee

PHOTO: a carpenter bee perched on a eryngo flower.

Carpenter bees are often confused with bumblebees because of similar size and coloring. The carpenter bee has a black abdomen and a black spot on the back of its thorax (middle section). That’s how to tell the difference.

2. Mason bee

PHOTO: a mason bee on an eryngo flower head.

Mason bees are in the Megachile family. The are also known as leaf-cutter bees.

PHOTO: a megachile bee is covered in pollen.

This mason bee has filled the “pollen baskets” on its hind legs with pollen from the eryngo, and they are now swollen and bright yellow. Pollen is also sticking to the hairs on its thorax and underside. It is a good pollinator!

Carpenter bees and Mason bees are native to our region. Honeybees are not native to the United States. I saw honeybees in the Heritage Garden, but they were not interested in this flower. Honeybees tend to go for sweeter-smelling flowers.

3. Red admiral butterfly

PHOTO: a Red Admiral butterfly is perched on a eryngo flowerhead.

The red admiral, with its characteristic red stripe across the middle of the upper wings, is  common in our area.

4. Azure butterfly

PHOTO: the azure butterfly's wings are smaller than that flower head it is perched upon.

This tiny gray-blue butterfly is an azure. Some azures are the same blue color as the eryngo flower.

A monarch butterfly also flew overhead while I was taking pictures, but it didn’t stop by. Again, the scent of this flower isn’t attractive to all pollinators. 

5. Squash vine borer (moth)

The squash vine borer larva can be a nuisance in a vegetable garden, but it is a beautiful and beneficial pollinator as an adult moth. Sometimes we have to resist the urge to judge our fellow creature as being good or bad. 

PHOTO: Picture of the moth perched on an eryngo flower head.

The squash vine borer was the flashiest visitor I saw on the flowers.

6.  Syrphid flies (hoverflies or flower flies)

When we think of flies, we tend to think of those annoying houseflies or other pests, but there are other kinds of flies. The Syrphidae family, also known as hoverflies or flower flies, feed on pollen and therefore serve as important pollinators for many plants. I found three species of syrphid flies on the eryngo.

PHOTO: flower fly hovers next to the flower head.

Flower flies resemble bees because of their yellow and black striped pattern, but this little insect bears the large eyes and short antennae that are characteristics of a fly.

PHOTO: flower fly on a leaf.

This syrphid is very small, only about a a quarter of an inch long. It looks a lot like the first, but it had a rounder abdomen. The pointed end is an ovipositor, so after inspection, I believe this is the female and the other may be male, so I counted them together.

7. Another kind of syrphid fly

PHOTO: syrphid fly on a eryngo flower

This syrphid fly is a little bigger and fuzzier than the previous one. It could easily be mistaken for a bee.

8. Mystery fly, possibly another syrphid

PHOTO: small black fly on a eryngo flower.

I was having a difficult time getting good picture of some of these small insects, and as a result, I didn’t get enough details to identify this half-inch-long fly with white triangles on the back of its abdomen.

9. Green bottle fly

Houseflies fall into the family of flies known scientifically as Calliphoridae, also called the blowfly family, and they were also represented on our eryngo plant.

PHOTO: green bottle fly seen from the back.

One view of this green bottle fly (genus Phormica) shows its iridescent green body.

PHOTO: Green bottle fly from the front.

The same green bottle fly can bee seen with its proboscis sipping nectar from the flower in this image.

10. Cluster fly

PHOTO: cluster fly on a flower.

This is the only image I got of another blowfly species, a cluster fly (genus Pollenia).

11. Tiger fly (I think)

Tiger flies prey on carpenter bees, which were feeding on the eryngo flowers, so seeing this predator around the eryngo makes sense.

PHOTO: a fly of some kind is perched on a leaf, partially hidden by the stem of the plant.

I could not get a good picture of this one, because it was hiding in the shadows under the flowers. The wing pattern suggests some kind of tiger fly. Its secretive behavior is also a clue to its identity.

12. Vespid wasp

The wasps I observed were far too busy collecting nectar and pollen to notice me. I had no concerns about being stung.

PHOTO: wasp perched on a eryngo flower.

Vespid wasps are a large family of wasps that include paper wasps—those insects that make the big paper nests. These insects live in colonies and they do sting when they feel threatened.

13. Black garden ant

I watched a few ants appear very determined as they walked up the stems of the eryngo, dipped their heads into the flower centers, and went back down the stem as swiftly as they arrived.

PHOTO: Ant on an eryngo.

The ants must have a colony living in the ground under the Eryngo.

14. Damselfly 

Where there are a lot of flying insects, there are going to be some predators. There were damselflies hovering over the blossoms, feeding on the flies, not the flower. 

PHOTO: bronze and blue damselfly perched on an Eryngo flower.

Damselflies are difficult to identify without getting a really good closeup of their abdomens and markings—and my picture wasn’t good enough. I believe this is some kind of spreadwing.

15. Assassin bug

Assassin bugs fall into the category of insects known as “true bugs.” I saw few assassin bugs lurking around the eryngo flowers.

PHOTO: an assassin bug hangs out at the bottom of the flower, probably about to catch another insect.

Assassin bugs and their kin have piercing mouth parts that penetrate their prey and suck the juices out. This guy wasn’t there to feed on nectar or pollen.

16. A spider web

Like the damselfly and assassin bug, this spider is hanging out somewhere under the flowers to prey on the flies, bees, and other insects that happen into its web.

PHOTO: Spider web that was underneath the flowers.

Spiders tend to set their traps and hide. I never saw the spider that made this tangle-web but I suspect it was well fed.

In total, I found two kinds of bees, two butterflies, one moth, six flies, one wasp, one ant, one damselfly, one assassin bug, and one spider—sixteen different bugs on this one bright, smelly plant!

The take-away from my experience is that scent is a really successful strategy for attracting pollinators. Like the titan arum, the Moroccan mountain eryngo produced a super potent blast of odor for a brief period time and then moved on to the next phase in its life cycle, which suggests that it requires a lot of a plant’s energy reserves, and may not be sustainable for a long time. This strategy works well  as long as the timing of the bloom coincides with the pollinators’ need to feed and ability to get to the flowers. 

I find this phenomenon fascinating. If you share my passion for plants and their relationships with insects, check out Budburst at budburst.org and find out how you can help scientists who need your observations to contribute data to their research. 


©2018 Chicago Botanic Garden and my.chicagobotanic.org

Pollinators are crucial to the health of the planet, helping with everything from the food we eat to the cycle of life. At the free Unearth Science festival this weekend, the Chicago Botanic Garden will celebrate pollinators with activities including a workshop on making native bee homes. We’ve got a sneak peek for you below.

Did you know that native bees are better and more efficient pollinators than honeybees when it comes to fruit trees? Honeybees carry pollen in sacks on their hind legs, which doesn’t always make it to the stigma of the flowers they visit (anthers are where the pollen grains are picked up; stigma is where they are deposited for successful pollination). Mason bees (Osmia lignaria) carry pollen all over their bodies, which means that the pollen has a greater chance of reaching the stigma for proper pollination. One mason bee can pollinate as many flowers as 100 honeybees. 

PHOTO: Mason bee (Osmia lignaria)

Mason bee (Osmia lignaria)

Mason bees pollinate a wide variety of flowers, in addition to fruit trees, with a particular emphasis on the rose family. They are generalists though, so they pollinate many types of vegetables too. If you are interested in growing fruit trees and vegetables in your yard, you may want to attract and support more mason bees.

Are you avoiding bees because they sting? Another reason to invite mason bees into your yard is that they are nonaggressive. Honeybees and bumblebees may defend their nests if disturbed, so bee skeps—or domed hives—are usually located on larger plots of land, not in typical backyards. Male mason bees do not have stingers, and the females only sting if they are trapped, so there is little reason to fear them.

We asked horticulture program specialist Nancy Clifton for a preview of her workshop at the Unearth Science festival with Northwestern University graduate student Marie Faust. The workshop, Native Bee Homes, is a free event that requires registration. You’ll find instructions for how to make a mason bee home below. Bring your questions about pollinators and other science-related topics to the festival, where dozens of scientists and horticulturists will be happy to answer them.

How to Make a Mason Bee Home

DIY native bee house

DIY native bee house

Supplies you’ll need:

  • Clean, 15-ounce metal can
  • Phragmite reed tubes
    (6 inches long)
  • 2¼-inch-wide bark ribbon
  • Cling floral adhesive (or similar putty tape)
  • Duct tape
    (camouflage blends in well)
  • Scissors
  • Rubber bands

Instructions:

Step 1: placing the reeds. They will stick out of the can quite a bit, so you can extend the lip of the can with duct tape around the reed bundle.

Step 1

Fill the metal can with as many reeds as you can tightly pack inside. Ensure the open ends of the reeds are facing out. Use duct tape to encircle the parts of the reeds that are sticking out of the can.

Wrap 3 strips of bark ribbon around the can and extension.

Step 2

Cut three strips of bark ribbon to wrap around the can and the duct-taped extension. Use bits of Cling adhesive to adhere the bark ribbon to the can in three sections, so it is completely covered.

Make a roof with bark ribbon and duct tape.

Step 3

Cut two 8-inch-long pieces of bark ribbon and duct tape them together along the long edge. Place this over the top of your can as a roof. You want to create a small gable that overlaps ½ inch over the end of the tube to keep the reeds dry when it rains.

Place the bee house against a flat surface in a protected area, with a southwest exposure.

Step 4

Use bits of Cling to adhere the roof to the house. If needed, further secure the roof with two rubber bands. Place the completed bee house fairly in a protected area, against a flat surface with a southwest exposure. Placing the house fairly high up ensures that bees will not mingle with people when entering and exiting their new home.

Leave your house out all summer and you should find mason bees filling the tubes with larvae. For information about storing and incubating mason bees for next year, visit seedsavers.org.

Sign up for the free workshop on making native bee homes with horticultural specialist Nancy Clifton and Northwestern University graduate student Marie Faust at the Unearth Science festival, April 20–22, 2018. You’ll make your own native bee home just as described above.


©2018 Chicago Botanic Garden and my.chicagobotanic.org

Native bees are critically important in pollinating our plants. This video provides easy-to-follow instructions on how to build a home for bees in your garden so they can continue to pollinate your plants all season long. This is just one of the many environmentally-friendly gardening practices that you can learn during World Environment Day at the Garden on Saturday, June 4, 2011. Visit www.chicagobotanic.org/wed2011 for more information.