Threshold means an entrance or door way. Threshold (door frame) for us Indians has lot of significance. Especially the threshold of main door. In olden days, houses of rich and royalty or those houses which were very big, temples and forts had huge doors and huge thresholds ie., the main doors leading into the house. I remember in my child hood, all the houses had thresholds (the main one) that were one foot wide and one foot high at the bottom. Even the rooms inside the house had thresholds but were in smaller size.The doors and thresholds were generally made of fine quality teak wood.
Decorating the upper portion of the doorways with torans, I am already covering that under the head "Torans". Here I am talking about the bottom portion of the door ways. Here after when I mention threshold, it refers to the bottom portion of the door frame. This is known as Chaukhat in Hindi and Gadapa in Telugu.
The threshold (bottom portion) is considered as a place where Goddess Lakshmi (Goddess of Wealth and Prosperity) resides.
Threshold art is the art of decorating the threshold with turmeric and vermilion. Since my child hood I have been fascinated by this art. Each household or rather lady of the household has its/her own way of decorating the threshold which has been handed down over generations.
How to apply turmeric and vermilion:
First of all the bottom portion and the sides of the frame (upto 1-2 feet) are washed with water to clean dirt and also to wet the wood. Turmeric is mixed with water or with sour curds (this gives a beautiful colour) into a paste and applied. Then it is decorated using red coloured vermilion and rice flour.