Before the first biker ever tattooed a Harley-Davidson logo on his arm, before Apple ever inspired the first MacHead to swear she would never -- ever -- marry a Windows user, Deere & Co was creating one of the enduring corporate cults.

For 172 years now, the company's products -- with their leaping deer logo and distinctive green and yellow iron -- have stirred something like love in the farmer's breast. Generations have come to count on Deere's plows, planters, tractors and harvesters to make their jobs a little easier.

Today, especially during the summer months, it is common to see small convoys of vintage Deere tractors, lovingly restored by retired farmers, popping and wheezing down rural roads in rallies that are rolling reminders of the brand's appeal.

In a way, Deere, now the world's largest maker of farm equipment, has enjoyed the same kind of loyalty with investors -- though that is about to be tested as it reports fiscal first-quarter earnings this week and updates shareholders on the fast-deteriorating global agricultural market.

Over the past year, Deere has outperformed its two primary rivals in the farm equipment business, Fiat SpA subsidiary CNH Global NV and Agco Corp, on Wall Street.

True, the company has managed to do this mostly by not falling as much as its competitors. But in this market, that's an accomplishment.

To an extent, that reflects the market's perception of the value of Deere's brand. But as the headwinds facing the farm sector intensify, analysts are beginning to warn the leaping deer may be headed for a hard landing.

Last Monday, JP Morgan analyst Ann Duignan lowered her estimates for Deere's full-year 2009 earnings. Among her biggest worries: the rapid deterioration in South American demand reported by Agco in its quarterly results as well as a growing sense among farmers in North America that they should wait for the economic dust to settle before making any big capital purchases.

At the time, Duignan said it was hard to say where we are in the cycle.

When the U.S. Department of Agriculture's Economic Research Service released its initial outlook for 2009 farm sector income two days later, Duignan, long a leading bull on the sector, jumped off the fence.

With the agency estimating a 20 percent year-over-year decline in net farm income, Duignan declared 2008 ag machinery sales were likely a peak.

CONSTRUCTION STILL AILING

The decline in U.S. farm incomes -- the first in a decade -- is not the only problem on the ag front for the Moline, Illinois-based Deere.

The ethanol industry that sent grain prices soaring last year is looking wobbly, a victim of overcapacity, weak demand and poor margins.

The global economy is in recession. And the credit crunch is hurting sales in what were recently the world's fastest-growing agricultural markets, including South America, Eastern Europe and Russia.

Adding to the company's woes is its construction and forestry equipment business, which was already grappling with the sharp drop in homebuilding that has hammered companies like Caterpillar Inc, Komatsu, Hitachi Construction Machinery and Terex Corp.

The trouble is no one is expecting that market to rebound in 2009. Last week, Terex warned as it released disappointing fourth-quarter earnings that the deterioration in that market was in fact accelerating and that it was getting slammed by order cancellations and delays in acceptance of deliveries.

And in three separate announcements over the past three weeks, Caterpillar has laid off, bought out or offered early retirement to nearly 25,000 employees -- or about 15 percent of its full-time global workforce -- as it struggles to deal with an accelerating deterioration in demand for construction equipment.

Confronted now by a slowdown in its key farming market, where sales of high-horsepower tractors and combines have risen by double digits for five years now, it is hard to see where the good news is likely to come for Deere in 2009.

As part of a report issued last week, the USDA said that in addition to falling farm incomes in 2009, crop receipts are also expected to decline. Given the high correlation between receipts and equipment purchase, Robert McCarthy, an analyst at Robert W. Baird & Co, called the forecast another negative indicator for machinery demand and manufacturers' production schedules.

Manufacturing