Putting Theory into Practice
Hannah Gravois holding Kacee's lead.

Learning about plants that devour flies gave 13-year-old Hannah Gravois of Sorrento an idea.  Could the plants be used to eradicate flies and make horses more comfortable?  The University View Academy 7th grader is an avid rider and she sees how flies make her horse, Kacee, very uncomfortable in the barn environment.  Hannah says the flies drive Kacee “crazy” since “She’s like a princess and stomps around.”  

Flies biting horse's leg

Kacee bites her legs where the flies lay their eggs and the wounds cause parasites, plus Kacee kicks to get the flies off or swishes her tail.  “You don’t want to be hit”, Hannah says.  

Using pesticides is the usual method of controlling flies, but not for Hannah.  “I personally don’t like pesticides”, she says with conviction.

That’s where the plants come in.  Hannah studied at the Audubon Institute in New Orleans for a month last summer and learned about carnivorous plants. Some are native to Louisiana, called Pitcher Plants.  
They’re shaped like pitchers of water, and close when flies crawl in, are captured and die.  “I find carnivorous plants very interesting.  I think this would be better to control the fly population” she says.   

Pitcher Plant

Hannah proposed her idea to the 4-H organization and is awaiting word on funding to put it into practice.  Her mom, Amy, says “I am absolutely thrilled she has thought it through and came up with the scientific method with limited funds”.  

This summer, Hannah will work on a preliminary hypothesis using non-carnivorous plants.  Marigolds, Lemongrass and Woodworm are considered repelling plants that keep flies at-bay.  She’ll fill the barn with them.   She may also include zebra-patterned horse blankets.  Zebras don’t have as bad a fly problem and experts say it may be due to the pattern of their hair, which confuses flies so they don’t land on the animal.   Next summer, she hopes to get the 4-H funding to buy the carnivorous Pitcher Plants to study their effectiveness.  

Large photo of pitcher plant

In the meantime, She’ll take care of Kacee and six other horses at the Purple Rein Farm. That takes up 25-35 hours a week.  Hannah will also continue to ride Dressage, but she says “Cross Country is my personal favorite.” 

She’s also in the process of painting a mural to celebrate another passion.  She loves to play tabletop role-playing games and was commissioned by Gamer’s Trinity on Lee Drive in Baton Rouge to do the artwork.  She is one busy 13-year-old.  


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