You've probably heard and read all you want to know about El Nino and the coming La Nina.

But listen up.

Elwynn Taylor, an Iowa State University meteorologist, says El Nino and its ultimate demise must be considered in your 1998 grain marketing plan.

"Exactly when El Nino begins to fade out and La Nina sets in will determine whether we have a drought or a bumper crop this year in the Midwest," says Taylor.

He's been preaching since early in the year that the earlier the warm waters of the eastern Pacific Ocean (El Nino) turn cool (La Nina), the greater the chance for drought.

"Historical data suggests this will be the case," he says.

Late in March, the National Weather Service projected that El Nino would fade away about the first of May. But by early April it appeared more likely to last through June.

"That's good news if you're looking for high yields," Taylor says. "We went into spring with soil moisture near field capacity throughout much of the Corn Belt. That means we already had nearly a third of the moisture we'd need for a normal crop."

Taylor says that, if El Nino faded away by May 1 and a strong La Nina developed, history suggests a 30% chance of below-average corn yields. The same data also suggests a 57% chance of an average crop.

However, if El Nino is still in place through June, Taylor's analysis suggests a 36% chance of higher-than-average yields, a 56% chance of average yields, and only an 8% chance of below-average yields due to drought.

"Based on what we've seen in the past, it would take a few weeks for hot, dry weather to develop, and we'd be past corn pollination in most of the Corn Belt."

If El Nino lasts that long, record corn yields are a strong possibility, especially in the central and western Corn Belt, believes Taylor.

"If El Nino hangs on through June and into July, historical data suggest western Corn Belt harvest prices could drop below $2 for corn and below $5.65 for soybeans," says Bob Wisner, an Iowa State University extension ag economist.

An earlier fade-out could be a precursor to a hot, dry period at corn pollination, cutting into yields but holding up prices.

"If El Nino fades out by the first of June, we're looking at a 25% possibility of below-average yields and corn prices going up to $3.50 or higher," Wisner reports.

He recommends this early marketing strategy:

"Weather uncertainty favors purchases of put options or minimum price contracts for corn," Wisner advises. "For soybeans, hedge or forward contract, and then re-own the beans with out-of-the-money calls until you have a clearer reading on summer weather.

"I hesitate to recommend hedging or contracting. With these two tools, a short crop on your farm could result in large margin calls or buy-back costs if too little grain is produced to offset contracts."

The bottom line, it seems, is to watch for a lot of weather-driven price fluctuation. Whenever the market offers a reasonable profit, sell a portion of your crop using futures or options contracts or minimum-price contracts at your local elevator.

At the same time, be cautious about the overall quantity booked until the size of your own crop is more obvious.