Why? Looks strange. Maybe cats just like it. I always wondered why my cat likes to pop out and almost one of the first things she does is to chew on grass.
Sometimes (thankfully rarely, it seems) a cat will chew on the next available thing, a house plant, and some of them are poisonous. You can see a list here.
I actually thought it was something to do with the digestive system of cat and a means to improve it - a bit like eating roughage for humans!
Some experts though it was a means to making themselves sick to throw up hairballs.
It seems that the jury is still out on this but the likely explanation is that the cat is chewing on (normally long grass) to extract the sap or juice in the grass as it contains a substance that is not normally obtainable in her diet and which is vital to her.
The chemical that the cat needs is folic acid, a substance that aids the body's production of hemoglobin. Hemoglobin is a substance in the red blood cells of the body that contains iron and which transports oxygen around the body in the blood.
Cats are not becoming vegetarian though. They are confirmed carnivores and the diet should reflect that.
Source: Cat Watching - Desmond Morris
Photo: reproduced under creative commons copyright Irregular Shed (Flickr)
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