A caterpillar in the bonnet, continued

As I continued my search for the seed pod raiders, I soon came across more plausible suspects than the lady beetle. I found numerous caterpillars not only suspiciously near both old holes…

... and fresh holes...

… but also chewing the holes…

… and feeding from within the seed pods.

Because the seeds are provisioned with enough nutrients and energy to support the initial growth of a new plant, they make tempting meals -- even considering the effort required to tunnel through the protective pod.  Thus, by the time the seed pods finished maturing, a significant proportion appeared to have been plundered by the large population of hungry caterpillars.

A caterpillar in the bonnet

The bluebonnets attracted many more visitors than just bees this spring.  Among these other visitors were caterpillars – which came to feed on, rather than from, the flowers.

A caterpillar feeding on the buds of a Texas lupine (Lupinus texensis).

However, the flowers were not the most enticing part of the bluebonnets for herbivores.  Soon after the seeds pods began maturing, they started to become riddled with holes.  Meanwhile, the seeds that should have been developing inside were damaged or even completely missing.

Texas lupine seed pods after a seed predator attack.

The first insect that I found in the vicinity of the holes was a lady beetle. 

A seven-spotted lady beetle (Coccinella septempunctata) by a freshly chewed hole in a Texas lupine seed pod.

Yet, nearly all lady beetles, including the one pictured here, are primarily predators of other insects, not of seeds.  Therefore, it seemed unlikely that the lady beetle was the culprit.  Then, what was making all the holes?  To be continued…

Happy Thanksgiving!

Have a Happy Thanksgiving...

An eastern chipmunk (Tamias striatus) nibbling on an unidentified something.

 ... and enjoy your feast (whatever it is)!

Rose hips partially eaten by a chipmunk.

Natural Current Microevents

Of the thousands of photographs that I take, only a few become featured on this blog.  However, now you can see some of the "microevents" that did not make it into larger narratives, along with other updates, at the new Facebook page for Natural Current Events!

A maple seedling just coming out from under the wing.

Spilling the beans

While I was in Florida, I was asked to solve a new mystery involving a very strange object that had appeared on the fence.

A mysterious and very large (6" x 2.5") seed pod that appeared on the fence.

Although it seemed to be a seed pod, it did not resemble any seed pod we had ever seen before.  However, back in December and January, we had seen clusters of what looked like bean (Fabaceae) flowers on some of the vines.

Yellow bean (Fabaceae) flowers that were frequently visited by ants.

Since the seed pod did not appear to be ripe, I turned to the internet to find out what kind of seeds were developing inside.  Surprisingly, the answer was something quite familiar -- for years, we had been finding the seeds washed up on the beach.

A brown hamburger bean (Mucuna sloanei) partly buried in the sand.

We brought many of these seeds home and most of them ended up in jars.  A few others were left by the gate – and one or more of these must have eventually sprouted and grown into the vines that now cover the fence.  After identifying the vine, I checked the outside of the fence for more seed pods.  Though there were none on the vine, I did find an older one that had fallen to the ground.

An earlier crop of brown hamburger beans (Mucuna sloanei).

Unsolved mystery

Recently, I have been seeing many fuzzy, white things floating through the air in the backyard.  Most of these are seeds.  Their silky hairs help them catch the wind in order to disperse away from their parent plants.

A wind-dispersed seed caught against a rose leaf.

However, this evening, the air seemed to be full of a new kind of white speck.  These specks appeared to be flying, not simply drifting on the breeze.  I followed one until it landed on a leaf.  It was indeed an insect, not a seed.  Its fuzzy, white appearance came from a fringe of white tufts around its abdomen.

The mystery insect on a lilac (Syringa sp.) leaf.  It is very small!

A close-up of the mystery insect.  From its wings, it looks like a parasitic wasp.

As far as I can tell, the vein patterns on the wings suggest that it is a parasitic wasp.  Perhaps these insects had just emerged from a host somewhere in the garden, but I'll have to leave this as an unsolved mystery for now.

The weevil within

The hollyhock seed pods are drying up now and rings of holes have become visible around many of them.  I was not surprised to see these holes, since in the past weeks I have seen many bugs feeding on the seed pods.  What did surprise me was that quite a few holes had something protruding out.

Something is sticking out of one of those holes in the hollyhock seed pod.

Intrigued, I began peeling open a pod.  Inside, in addition to the hollyhock seeds, I found a large group of hollyhock weevils (Apion longirostre).  Once exposed, the weevils quickly dispersed in search of cover.

A hollyhock seed pod full of hollyhock weevils (Apion longirostre).

How had all those weevils gotten inside the seed pod?  Through holes -- but not the holes in the seed pod.  There were matching holes in the seeds themselves, and not all these holes were empty.  Several had the long snouts and antennae of yet more weevils sticking out.  I broke open the seed pictured below to reveal the weevil that had grown inside.

A hollyhock weevil (Apion longirostre) developing inside a hollyhock seed.

Earlier this summer, a female hollyhock weevil must have laid her eggs in the ovaries of the flower.  As the seeds developed, so did the weevil larvae, consuming the seeds from within before pupating and finally emerging as adults.

Please stop bugging my plants

Just a few hollyhock flowers, at the very tops of the stalks, are still blooming.  Only occasionally does a bee come to visit one of these flowers.  This is a vast change from earlier in the summer, when the flowers were abuzz with a frenzy of pollinator activity.  Proof of this past pollinator attendance remains further down the stem, in the form of pods packed with seeds. 

A ring of hollyhock (Alcea rosea) seeds is visible within the seed pod.

The multitude of seeds has made me hopeful that next year we could have many more hollyhocks growing in the garden.  Unfortunately, hordes of insects have another plan for these seeds: dinner.

A stink bug (Pentatomidae) feeding on hollyhock (Alcea rosea) seeds.

Among the worst offenders are several species of true bugs.  These bugs sit on the outside of the seed pods and pierce both the outer wall and the seeds with their long, straw-like mouthparts.

A seed bug feeding on hollyhock (Alcea rosea) seeds.

Since the bugs are feeding on seeds before they have completed developing, I can't even harvest them to keep them safe.  I just hope that some seeds will survive this gauntlet of seed predation.

An immature bug feeding on hollyhock (Alcea rosea) seeds.