Month-ends are, by repute, often weak periods in Chicago, spurring position closing by funds as they tidy up portfolios and raise cash to meet investor redemptions.
(And in the Paris commodities market, a certain reluctance may be inspired by the prospect on Tuesday of the May 1 French national holiday.)
Still, a declining trend was not so easy to call this time, given the momentum the market gained in the last session from a huge order, thought to be by China, of US corn, and some soybeans too.
Besides, the general markets mood was positive, with London
All this left a somewhat mixed picture among agricultural commodities.
Sure, corn was higher as of 09:00 UK time (03:00 Chicago time), adding 0.3% to $6.55 ¼ a bushel for May delivery, a contract whose expiry process begins today.
This time, it was the better-traded July lot which fared better, gaining 0.4% to $6.28 a bushel, as investors continued to react to Friday's surprise Chinese purchase announcement, which took well above 2m tonnes purchases in a week.
"The bull in corn was awakened as we ended the week," Mike Mawdsley at Market 1 said.
The "weak link" in the complex is new crop, Mr Mawdsley added, with expectations of a record US harvest ahead, of well over 14bn bushels.
Still, the December contract too made ground, up 0.5% at $5.41 ¼ a bushel, given a healthy boost from the fact that most of China's order on Friday was for 2012-13 delivery.
"The large new crop purchase does indicate interest at these price levels," he said.
Besides, there were rains over the weekend in some western Corn Belt areas which, while they could use the rain, raise further doubts over the idea of an ideal US spring for sowings. While perhaps true for Illinois, the second-biggest corn growing state, it has been less true for top-ranked Iowa.
"There are numerous reports of rainfall amounts over one inch" on Friday/Saturday, largely in South Dakota, Nebraska and parts of Kansas, WxRisk.com said.
And corn is looking more healthy from a chart perspective too, after ripping in the last session up through 10 and 20-day moving averages, for the old crop contracts.
One other factor, technically, which corn achieved in the last session was to regain a healthy premium over fellow grain
And that premium only continued to grow on Monday, in the apparent absence, so far, of reports of frost feared for the weekend proving such a threat.
The fast-developed state of the US winter wheat crop has left it particularly vulnerable to cold weather.
(That said, freeze jitters are not over, with WxRisk.com saying it could "not rule out the possibility of a frost or freeze scare" further into May.)
While Saudi Arabian did make a big wheat order over the weekend, of 450,000 tonnes - purchased from Argentina, Australia, Canada, the European Union and the US at an average price of $316.92 a tonne including freight – the grain does not have the tight fundamentals of old-crop corn to support it.
Chicago May wheat, also to start expiry, eased 0.1% to $6.41 ¾ a bushel, while the better-traded July lot shed 0.4% to $6.47 ¼ a bushel, finding the prospect of the 50-day moving average, at a little over $6.51 a bushel, too daunting.
The latest was by Informa Economics, which cut its estimate by 5m tonnes to 40m tonnes.
"Many in the trade believe further reductions are imminent," Brian Henry at Benson Quinn Commodities said, while noting reasons for soybean bulls to tread cautiously nonetheless, given huge net positions run up by funds and speculators, which will at some point unwind them.
"Soybeans are overbought, which should trigger profit-taking when the market seems to lose momentum," Mr Henry said.
"But unless the cash market signals impending weakness in old crop soybeans, the trade will likely remain choppy with a higher bias."
Chicago's May lot was 0.5 cents higher at $14.97 ¼ a bushel, with the July contract up 0.3% at $14.97 ½ a bushel.
Among soft commodities,
The fibre has continued to gain support from decent US weekly export data revealed on Thursday.
Still, volatility may lie ahead for cotton too today, with India announcing earlier it is to reopeni its cotton exports, without restriction.