Jean Rosenbaum, age 9, of Philadelphia, Pennsylvania, for her question:

What plant gives us pistachio nuts?

Each kind of nut has a special flavor of its own. The taste of pistachios is faintly tinged with almonds and several mysterious spices. The little nuts are not so chewy as crunchy brazils. But when cooked, they share their delicate flavor with fish, poultry and meat dishes.

The pistachio tree grows as high as six tall men.and it spreads out its wide, shady branches in all directions. Through most of the year, its branches are decked with fistfuls of long green leaves and the greenery gleams with waxy resin. It is a handsome tree. But, sad to say, we cannot coax it to grow where the winters are cold. The pistachio is a native of the warm, dry regions around the Mediterranean Sea. It also feels at home in certain sunny regions of southwestern Asia. Sometimes it grows in California and our warm southern states. But it cannot abide too much rain or spells of frosty winter weather.

One pistachio tree growing alone in a park or garden is a handsome sight. But this lone tree will never bear us a crop of delicate little pistachio nuts. Each pistachio tree is either a male tree or a female tree. The nuts are seeds for a new generation of pistachio trees. And the seeds must have two parents. The life of the next generation begins when tiny male and female plant cells meet and merge together.

When the time comes to hand on life to the next generation, most trees grow lots of male cells and also lots of female cells. Both kinds grow on the same tree where the breezes and insects can bring them together. But the pistachio tree cannot do this. So a male and a female tree must grow fairly close to each other    or there will be no crop of pistachio nuts.

The male pistachio produces grains of golden pollen. The female tree grows clusters of tiny flowers. When the pollen is ripe and ready, it blows off into the air. The breezes waft the tiny grains around and dozens of them reach the flowery clusters on the branches of the nearby female tree. The pollen merges or fertilizes the special egg cells in the flowers. When this magic is done, the flowers begin to form tiny seeds. After many sunny days, these seeds become clusters of pistachio nuts.

Some pistachio nuts are an inch long but most of them are smaller. They are shaped like chubby melon seeds and encased in smooth, hard shells. A ripened shell often cracks open at one end somewhat like the two shells of a clam. The nut inside the shell has a thin skin of rosy yellow or blushing pink. When this tinted skin is husked away, we come to the delicate kernel of pale nut meat.

Pistachio trees are plentiful in certain warm, dry parts of Asia and Europe. The lucky people who live there harvest loads of the tasty little nuts. They make crunchy snacks by soaking them, shells and all, in tubs of salty brine. They husk and eat all they want. And they still have enough nut meats to be crushed until they give up their rich pistachio.

In our country, pistachio flavor is a treat that we cannot afford to enjoy every day. We grind up the soft little nuts to flavor ice cream where they look somewhat like overgrown grains of rice. When cooked along with savory dishes, they add their own Sunday flavor of delicate almond and spices. It is sad that we cannot coax more pistachio trees to grow in our country so that we could enjoy their tasty little nuts on Sunday and every day of the week.