The Isu is a tiny species of local Sarawak durians. Only the size of your palm (measuring 8 inches or less than 90 cm) it usually gives you about 8 succulent seeds in each fruit. But you can be surprised by the amount of fleshy durian you can eat. The flesh is fragrant and "lunak" or rich and soft and buttery. It is just nicely sweet. Unforgetable is the word for Isu if you can get the right one that is.
Because of global warming the isu is now available even in July in some places. Years ago it could only ripen in December around Christmas time. And it looks as if when the upper river has this fruit in the year the lower river does not have it. Sometimes the isu does not fruit at all through the whole valley in one single year or two.
Those who believe in mysticism would say that the "fairies" are not happy. The fish and animal life and the fruits may be gone too because of ecological disturbances in my opinion. But how do you explain such things to the elders who have lived in the jungles for a very long time peacefdully and have not gone to school? They have seen bulldozers coming into their environment and have accepted men and machine willingly.
A good bunch of three or four isu can set you back RM15/- to RM20/- . But do not be taken for a ride when the vendor tells you that the isu is from his mother's trees. Some of the isu you get in town can be stolen from someone's garden (as is often the case) or taken from the jungle or abandoned temuda (small holding). Very few people grow the isu nowadays as modern farming has been promoting the Thai varieties or the "government" varieties.
One of the best species of the king of the Fruits in Malaysia is called Mou Tang and sold at 30 ringgit per kg in Selangor seldom fails to delight customers and connoisseurs but I will go for the "isu" any time.