Early maturity factors

by | May 23, 2019 | Crop Watch

The beginning of the fourth week of March has arrived. Typically, the last of the beans are being planted and many of the early planted corn fields are nearly ready to spray for grass or broadleaves. Guys or gals who were planning to do an early sidedress are getting their equipment ready or have already begun that task. The month of June is just around the corner and the time when the corn does much of rapid growing. Not in 2019 for much of the Cornbelt and all of the farmers and Ag business people who are wondering when if ever we will be able to put in a full week of field work. Last week it looked like the clouds were finally parting and corn and bean growers in all the major northern Cornbelt states could push the percentage of planted acres up closer to the norm. By Tuesday or Wednesday there were many people working the ground or planting thru northwest Iowa, SW MN and SD as the temperatures were warm and drying winds were drying the topsoil. Quite a few of their other fields still needed another week or so to be completely ready thru the low spots.

Last Friday our weather prognosticator put out a bulletin last Wed at 9:12 saying a large energy pulse was setting up over SE Iowa, meaning heavy rains in the four to six inch rains were being set up for the area. This spring those bulletins have been accurate. So as of late Sunday afternoon, after substantial rain from Friday night to Sunday morning, all fieldwork was on hold until further notice.

The markets finally woke up and began making moves to the upside. The desk traders began to finally realize that rain does not always make grain and the delays due to the wet weather were putting the 2018 corn crop in jeopardy. With the prices the board has been offering the much scoffed at ‘Prevent Planting’ option that has never been worth much looked more palatable. At this point it is anyone’s guess as to how the crop prospects will look in two to four weeks.

Purdue Wisdom

Later this week if we have weather that allows us to get back into the fields, while our corn planting counterparts in ILL, IN and OH remain wet the fact that two of the big-I corn states could be down on corn acres would be positive for the markets. When Bob Nielsen, a well-known University Agronomists uses the phrase “It’s time to cut bait and get the corn planted or else” you realize he is acknowledging the optimum planting window is getting narrow for his the eastern state. They do not have nearly as much tile installed as we do here and they run a greater chance of receiving Gulf Moisture. As their acres go, so go grain prices in the western Cornbelt.

Early Maturity Factors

Unless bean prices make a quick recovery the chances of earlier corn hybrids replacing full season corn rather than soybeans looks more realistic. This scenario is always a very mixed bag for seed dealers and seed companies as all of their careful planning, fuel and labor expended so far went to waste. In much of the state the 108 to 112 day hybrids have delivered the best yields and overall performance the last five or ten years. The later freezes and the corn dying early from diseases let growers planning longer RM corn that they used to. The added bushels boosted the gross incomes into the plus range. Now sticking with those maturities looks less likely as the middle of this coming week looks wet.

A number of forecasts predict a warmer and drier summer, but if some unseen forces are manipulating the weather (look up weather warfare) those hot temps we would normally expect may be substantially cooler than predicted.

If a crop needs to be pushed along then foliar fertilizers or high levels of biological activity can speed plant development. Typically, higher the P levels in the soil or in the cells will help push the corn or bean plants along. The P serves as the energy transport mineral in plants. If the stated goal is to maximize the amount of energy gained in visible and non-visible frequency, then growing a deeper layer of the chloroplast containing cells could do that. Those layers are referred to as the mesophyll and palisade parenchyma. Applying silica fertilizers in the monosilic acid form will perform that task.

In a number of articles, I have read Ag people state that hybrids can early themselves up and require fewer days to reach maturity. Has anyone done growth chamber work to verify this? What I would postulate is going on is something that was discussed at Univ. of Illinois crop conference a number of years ago by a climatologist/agronomy team. They were proposing to make the measuring and recording of GDUs more accurate by graphing the hours of heat rather than just the daily highs and lows in the 50 to 85-degree range. When you think about it: if the temp is at 49 degrees except between noon and 1 pm when it jumps up to 86 degrees and then cools off to 49 by 1 pm, by current calculations the crop will have gained 23 GDUs in that day. Versus when the temp starts at 49 degrees and gradually climbs in an even curve to reach a high of 86 F and then gradually cools off to 49 F after dark. In situation #2 the plant has many additional hours of heat to photosynthesize with, even if the GDU table says both days contained the same heat units. The nights are warmer during June thru August and the hours of heat are greater. The hours of sunshine are typically also greater in July and August. Now if the nighttime temps stay above 70 the plants burn up a portion of the starch they formed during the daylight hours subtracting some of the yield. This is where the StressTech product helps the plant tolerate heat up to 160 degrees.

The emphasis then if an incremental move to earlier hybrids is mandated is to find earlier hybrids that are able to move south of their regular zone of adaptation. Heat and disease tolerance could be important characteristics, especially if the season continues wet with many hours of leaf wetness and dews. This means that Tar Spot could become more of a problem in 2019 than is has been so far.

Alfalfa Scouting

With the high amount of legume seeding not surviving the heavy snow cover and extreme cold in the northern states one of the best cash crops could be good alfalfa hay. To achieve top yields insects should be scouted for with timely pest control if needed. The first insect that could be found in IA, MN, and S Dakota will be the alfalfa weevils. The adult weevils over winter in the soil in or near to the fields they were hatched in last year. Their appearance and peak activity is typically after 575 heat units have accumulated. I have been scouting fields in IA, NE and SD and have not found any yet, but producers need to remain vigilant. I have not spotted any of the leaf hoppers yet, but any southwest air coming in could bring in their populations.

Later than Planned SB Planting

One of the cropping facts that has to be partially credited to producing higher SB yields the past few seasons is that more acres are being planted one to two weeks earlier than what used to be the norm. This allows more podded nodes to form contributing more pods and seeds. Conversely the later planting date in 2019 could lead to lower yields due to fewer podded nodes. The common recommendations include: narrowing up the row width to shade the ground earlier rather than letting sunlight fall onto the soil instead of bean leaves. The negative of this is that they could increase the incidence of White Mold. Other late planting tips include: Increase seeding rate slightly; apply cytokine hormones to the plants by V3 to V4 to form additional branches and roots enough to close the rows earlier; adopt or continue to use a foliar fertilization program to plump up the seed size. Your goal in applying K, S, and Mg in a mix like NutraBoost is to supply the minerals the plant needs later during the grain fill time. Your goal is to produce 2,000 seeds per lb. or larger rather than 2500 per lb. or smaller.

Bob Streit is an independent crop consultant and columnist for Farm News. He can be reached at (515) 709-0143 or www.CentralIowaAg.com.