The princes had completed their education. Every day, small examinations were conducted to test them. On the final day too, their master put forth a small test.
The master called the princes and asked them to look around for plants which were of no use. The princes assembled again by evening and showed the plants they had collected to their master. He observed each plant and kept it aside.
As the princes finished showing their plants, the youngest prince came running to join them. He was late and came empty handed too. The master asked the prince the reason for his delay and he said, ‘Kindly excuse me, my master. I searched and searched. But I was unable to locate a plant which was of no use. That’s the reason why I’m late.’
Hearing this reply, all the princes broke into peals of laughter. But the master hugged the youngest prince and praised him. Then the master told the youngest prince, ‘Son, there’s nothing like a useless plant. All plants have some use or the other.’
The youngest prince was then declared the winner.

The children who stay in rural areas know the names of many trees, plants, insects and birds. The children are aware of the activities of the insects and birds such as what they eat and where they live. But people living in urban areas don't even know the names of many plants, birds, animals and trees.
At present, we only know names of few plants out of which we eat almost all. We know the names of vegetables, fruits and flowers. We don’t know some plants which are called ‘weeds’.
It is estimated that globally almost 60 billion dollars worth of trade and commerce is carried out in the name of medicinal herbs and spices. In our country, nearly 15 thousand medicinal herbs have been identified out of the 49 thousand species of plants. Out of them, 9 thousand medicinal herbs and spices are used in traditional health care systems like Ayurveda, Unani, Siddhi and Homeopathy. The herbs are also used in the rural and tribal medicinal systems. The WHO estimated that 80% of the people in the developed countries are also depending on traditional health care systems. They are using herbal medicines for primary health care. But the knowledge about the traditional medicinal plants is becoming less and less every day especially among the local rural residents and it may soon disappear.
If we don't extract the medicinal values from the medicinal herbs, we will forget their existence, their importance and use.