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What happens when you send an entomologist to visit a rose garden?

There will be some photographs of roses, of course.

 

But not only roses.

There will be even more photographs of insects.

Isn't the contrast between the dark red rose and the light green aphids striking?

If there are aphids, there will be lady beetles.The adult in this photograph is a convergent lady beetle.

And lady beetle larvae. This one is an ashy gray lady beetle larva. It is searching for aphids to eat.

  The larvae of the green lacewings also eat aphids.

This green lacewing egg looks like it might already have hatched.

The fly might have been attracted by the aphids, as well. Flies will eat the honeydew the aphids release.

The assassin bug was probably interested in the bigger insects, like the fly.

Butterflies visit roses, too.

So, yes an entomologist will spend more time looking at insects, but he or she just might enjoy the roses, too.

What about you?

Roses and insects provided by the rose garden at Mesa Community College.

It's hollyhock season again.

Some plants just have flower buds.

Others are flowering.

Once again, having a certain kind of plant means having a certain kind of insect.

In this case, the insects are oblong-winged katydid nymphs.

Wow, those antennae are so long.

I checked, and I had found the same kind of katydid nymphs on May 1, 2013. They were also on hollyhocks.

I only have a few hollyhock plants in my yard, and I'm pretty sure none of my immediate neighbors have them. I wonder how the katydids even find them, let alone show up with such regularity.

I guess if you eat mainly hollyhocks, you're probably pretty great at finding them.

The rush milkweeds are lovely this week.

They are flowering.

Here is what the plants looked like on March 19, a month ago.

The stems were covered with oleander aphids.

On April 17, 2018 you can't find a single aphid.

What did I do to get such clean plants?

Nothing. Let nature take its course.

Insects like aphids have boom and bust cycles.

Back on March 19, these aphids were under attack. They were turning into mummies, which means they were parasitized by tiny wasps.

The aphids were also being eaten by flower fly larvae, aphid flies, and a few other insects.

Inside, the plant might have been mounting a defense, too. Plants can increase their chemical fortifications in response to insects feeding on them. Milkweeds are well defended because they contain cardenolide toxins, as well as a milky latex. The aphids can overcome the plants toxins better than most insects, but eventually it is probably has a toll and the aphids are weakened.

Although they are gone right now, the oleander aphids are likely to be back again. It is a natural cycle.