Night of the Living Dead

Dateline: October 31, 2014*

Petrified Bird Grasshopper (Schistocerca sp.) high atop some Bluestem grass (Andropogon sp.)

How does one control pest species such as grasshoppers and plant hoppers?  Often Mother Nature takes over control TO control.  Grasshoppers and other pests have some natural predators besides birds, and it isn’t just fauna.

grasshoppers infected with Entomophaga grylli have lifeless eyes

Think PATHOGENS… disease-causing agents!  All natural, no chemicals involved.   In recent times I ran into two examples of this phenomenon in the form of fungi.

I always knew that a fungus had an important role in the web of life, but in my mind it had more to do with the ability to break down organic materials and provide nutrients rather than helping in our quest to control pest species.

They pose for hours on end

My knowledge base was expanded when I found a grasshopper that seemed content to vogue for hours on end for my camera.  Then I realized that the poor thing clinging to the top of some tall dried grasses was actually petrified, as in dead, not merely scared.  I didn’t think that some ghost had snuck up and scared the life out of it, so I investigated a bit further.

There is a fungus that belongs to the Entomophaga grylli species complex, which is grasshopper-specific.  Often called “summit disease”,

The name is derived from the fact that infected individuals climb to an elevated location (summit) where they die. This elevated location helps the pathogen to spread because it is more likely to drip or blow unto foliage below, where it can be contacted by healthy individuals as they feed on foliage. Entomophaga grylliis not evident because the spores develop inside the body of the grasshopper. However, the dead grasshopper eventually disintegrates, allowing the fungal spores to be dispersed. The principal evidence of infection of E. grylliis the peculiar behavior of the dying and dead grasshoppers: they grasp vegetation.”

crawling up to the “summit” on Goldenrod (Solidago sp.)

As you can see in the photographs, it is very effective.

Another day I was back by the Saw Palmetto (Serenoa repens) shrubs and I noticed some type of plant bug sitting motionless.  This is not all that unusual as there is even one particular insect that has a common name based on the fact that it favors palms…the Palm Flatid Planthopper (Ormenaria rufifascia).  Although called a plantHOPPER, most of the time when I see them they are stationary, and don’t’ seemed concerned with moving all that much.

Palm Flatid Planthoppers have rather attractive, bright colored markings

This pale green looker seems benign enough, as I have never noticed major damage cause by this species. This may also be because I have many saw palmettos sprinkled among a great diversity of other Florida native plants…no monocultures here.

I was taken by a new observation and what I thought was a new type of Planthopper.  On closer inspection, I realized that this indeed was one of the Palm Flatids, it just appeared to be in a costume of sorts.

Is the planthopper dressing up for Halloween? The coloring seems ghostly

It reminded me of emerald moth caterpillars that don bits of foliage in an attempt to disguise themselves.  I figured this was a similar situation.  I quickly found out that this creature was not gathering the adornment on it’s own.  Something was growing on it.Seems this is one of the Cordyceps species, an entomopathogenic fungus (a fancy way of saying a fungus that parasitizes and kills insects/spiders).  While often a beneficial fungus used in medicinal applications, this one does a job in the garden by disabling the planthopper.  Natural, environmentally friendly and interesting to observe.

As it deteriorates further, it releases spores to find living insects and start the process over

So, if you find an insect that seems to be overly willing to hold a pose, consider that maybe you are observing another interesting phenomenon in which Mother Nature keeps things in balance in your beautiful wildlife garden.  Natural biocontrol.

Happy Halloween 2014!

*This tale was originally published by Loret T. Setters on October 31, 2014 at the defunct national blog beautifulwildlifegarden[dot]com. Click the date to view reader comments.

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