Ms. Walking Stick

My garden is magical, or at least it seems that way to me because every time I work in my garden, I meet someone new.

This week I was cleaning out a dead lemon grass plant. I’m sure you can imagine what that is like – a crown of dried brown stalks crowded together. It was easy to dig up with my shovel, and in no time at all the pot was empty, but my shovel had acquired a hitchhiker – Ms. Walking Stick.

She was so timid. She huddled on the wooden handle, being intently still and trying to blend in. I was thrilled to meet her and tried to get her to talk to me, but she just cowered closer to the handle, saying nothing.

Immediately my imagination went into overdrive. What a fascinating character for one of my stories. Can’t you just see her: thin, no make-up, mousy brown hair, washed out brown striped dress, standing in the corner between the lockers and the wall at the bus station, trying not to attract attention. When one of the off-duty bus drivers walks by and asks if he can help her, she hunches her shoulders together, wraps her arms around herself, and shakes her head quickly, saying nothing. Eventually, he moves on.

Poor Ms. Stick. I had to help her, so I started researching. It turns out that the common name for Ms. W is, “two-striped walking stick,” but the scientist call her Anisomorpha buprestoides (Stoll) (Insecta: Phasmatodea: Pseudophasmatidae). Of course, I didn’t call her that – it would have been rude.

I bet you're wondering how I knew she was a Ms and not a Mr. It’s because of her size. The female walking sticks are much larger than the males.  

“Anisomorpha buprestoides is a large, stout (for a stick insect) brown phasmid with three conspicuous longitudinal black stripes. Females average 67.7 mm in length; males are smaller and more slender, averaging 41.7 mm.” (Thomas, 2014)

Ms. W has a large family. She has cousins and relatives all over the southeastern United States. They eat the leaves of plants and shrubs: roses, oaks, rosemary, lyonia, crepe myrtle and many others. The walking stick family is quite numerous, but they are also careful, and Ms. W is no different. I don’t mind someone like her eating a few leaves off my rose bushes and trees because she’s so careful not to defoliate them.

In the fall, when Ms. W is ready to lay eggs, she will dig a small pit in the dirt, deposit eight to ten eggs in the pit, and cover them over before moving on to a new egg-laying site.

She was so tolerant of my carelessness. I had destroyed her home, woken her up in the middle of what is her sleeping time (Ms. W is nocturnal), and then leaned in close to her, invading her personal space as I took pictures. She could have taken her frustrations out on me. She has a very powerful defense mechanism, especially as close as I was.

Walking sticks like Ms. W have two pores in the thorax just behind their head. Two sac-like glands, functional from birth, are located there and used to repel predators. The walking sticks are excellent marksmen. They can aim their discharges up to 30 to 40 cm with consistent accuracy. They aren’t stupid either. With predators like ants, they wait until the ant prods them before they spray, but with birds, they spray in advance. Active ingredients of the secretion have been identified as a terpene dialdehyde. It has proven effective at repelling ants, beetles, mice, and birds. Some predators, like opossums, deliberately irritate the stick insects until they deplete their reservoir of defensive spray, usually after about five sprays in a large female like Ms. W. Then when they can no longer defend themselves the opossum eats them. It would take Ms. W one to two weeks to replenish her depleted reservoir, assuming she didn’t get eaten first.

“Although Gray (1835) mentioned the defensive secretion of Anisomorpha burestoides, the first account of its effect on humans that could be located was by Stewart (1937), who wrote about an incident in Texas: ‘The victim was observing a pair of Anisomorpha buprestoides … with his face within two feet of the insects, when he received the discharge in his left eye … The pain in his left eye was immediately excruciating; being reported to be as severe as if it had been caused by molten lead. Quick, thorough drenching with cool water allayed the burning agony to a dull aching pain. The pain eased considerably within the course of a few hours. Upon awakening the next morning the entire cornea was almost a brilliant scarlet in color and the eye was so sensitive to light and pressure for the next forty-eight hours that the patient was incapacitated for work. Vision was impaired for about five days.’ Symptoms gradually disappeared and there were no lasting effects.” (Thomas, 2014)

Ms. W was nice to me, and she became much more relaxed as we visited. I told her all about my plans for the garden, and although she said nothing, she seemed to approve. Eventually, it was time for me to go inside, so I found her a new home. I thought she might like a large flower pot with a rubber tree growing in it, but evidently, she doesn’t like rubber tree leaves. Toby and I checked on her this morning, and she had moved on.

Walking sticks, like Ms. W, have a lifespan of about two years, so maybe I’ll see her again one day. I hope so; she’s fun to have around.

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