LOS ANGELES, CA (Catholic Online) - For farmers working in isolated areas, fertilizer is an essential -- but expensive ingredient.

"Fertilizers represent about 20 percent of the input costs in rice production for farmers," says soil scientist Roland Buresh at the International Rice Research Institute. "So it's really quite important."

Buresh has spent years researching optimal fertilizer conditions. He says that fertilizer on fields is a very delicate proposition, as too little means lower yields and lower profits; too much wastes money and causes pollution. Because every farmer's field is different, figuring out exactly how much to use is a complex decision.

Buresh and his colleagues have come up with a set of key questions that will help farmers make that decision. "The unique thing about some of these decision tools is really how simple they are," he says. "The questions we're asking are really readily answerable."

Farmers will soon be able to answer those questions using their mobile phones.

When the program launches in the Philippines in a few weeks, a farmer can call a toll-free number and hear a recording in his or her language that will ask questions about the size of the field, how much rice it produced last season, sources of natural fertilizers such as rice straw or sediment from river flooding, etc.

The farmer answers the questions using the keypad on their mobile phones. A computer does the calculations and sends a text message with the amount and type of fertilizer to apply.