Today we share some comments from Dr. Ron Heiniger, NCSU Corn Specialist, shared last week regarding the dry weather and small corn. He discusses what the corn plant is going through, how it could effect the corn production at harvest time, and how manage going forward.
Today we share some comments from Dr. Ron Heiniger, NCSU Corn Specialist, shared last week regarding the dry weather and small corn. He discusses what the corn plant is going through, how it could effect the corn production at harvest time, and how manage going forward.
welcome to crop sense presented by North Carolina Cooperative Extension. I’m Jacob Morgan a field crops agent with North Carolina Cooperative Extension. Today we have some information from Dr Ron Heiniger, Professor and Extension Corn Specialist with NC State University. This talk comes from the meeting Dr. Heiniger presented at last week regarding corn in this early season dry weather. Hope you enjoy. As wes mentioned i made a report on the corn growers newsletter that I’m just going to echo basically here and it sort of echoes what Wes has said and Rod and uh to some extent it's a little behind in the in the piedmont because they did wait a little longer to plant but uh we're off to a really good start uh this season. We didn't have a lot of rainfall temperatures on the average work yeah it's been cool and we've had some freeze um close freeze events but uh it's not been like last year where we had a freeze on the 9th 10th the 11th of may that was very strong across the northern counties and we had wet wet wet weather. We were struggling to get corn in it was all over the place um we've had as good as planting season, and if Scott Tilley was on he actually got some good data here showing that the emergence was as uniform this year as any of the times he's tested in the last three years. So I agree with Wes i think we're off to as good start as I’ve seen here in North Carolina, with corn anyway, so I’m really excited because all our data points to the fact that if you get off to a good start at least you got a decent chance of maximizing yield potential through the season. Now that doesn't mean we're not going to have challenges that we already are with this dry weather but at least the crop has an opportunity to develop the root system. At any rate uh we're off to a good start that brings me to the challenges that we are facing here and that is dry weather uh what can i do about dry weather. I've got number of calls from growers my corn starting to roll up what it's really dry. I haven't gotten any rain some of these like Pender county down there you guys have been especially uh unlucky to miss a small shower. So what can we do about this? Well of course the answer there is I not a whole lot now. First of all the stage of growth is critical here that's why I recommended during the winter season not to get a huge hurry planting because the farther along the corn is the more impact dry weather has and the smaller the corn plant is the less water it requires the less impact the dry weather is going to have. So if you've got corn that's V5 to V7 what it's doing right now is it's finishing uh it's going through that that differentiation. It's going from producing leaf area to producing the flower the ear and the tassel. That's where we talk about make a number of rows around the kernel so what it what. This drier weather is having an impact on primarily here at v5 the v7 is it's going to shorten up the inner nodes and it's going to start to impact how many kernels. Now how does it impact that? It impacts that by reducing photosynthesis so until we get leaf roll we're not hurting this corn and I see a number of guys as I’ve driven here with what a little gas. By the way we ought to have a gas report to see whether I could get in place now. But as I’ve driven around well I’ve noticed some guys turning on these irrigation rigs and because they think it's too dry. Well I wouldn't do that until I start to see some leaf roll on some of this corn because you can quickly you don't need a lot of water. So it doesn't mean you need to leave this crop in you can wait to start to see some stress here for these guys with some irrigation. Why am I not happy about them turning it on too soon because as long as you're not getting leaf roll what the corn is doing is putting roots down. That's a good stuff from our probes last year is they proved definitively when it turns dry corn roots start growing quicker and so what's happening right now is we're getting roots moving down through the soil at a higher rate. So I want that to happen that's a good thing that's impact of this uh dry weather as long as these leaves aren't rolling. Why I don't want to I don't want to make that corn get its water from the top I wanted to grow roots a little deeper. Well I’ll talk about that a little more in a second here so v5 to v7 as long as we're not going to leaf roll we're growing roots. We're okay but the moment we get roll, leaf roll, now we're starting to impact the photosynthesis and we're starting the impact first thing is the impact is height plant height internode length. Then as that leaf roll continues if you look at the irrigation guide that I have, it takes about 20 days of leaf roll before it has a significant impact on yield. So that's how long, takes some time for this to impact these smaller plants as far as yield potential. So I’m not overly concerned. Now the reason I’m so a little bit happier right now is temperatures were cooler but if we start getting days up in the 90s and over 90s and this dry, now we got trouble big trouble because we'll start to reach leaf temperatures of 95 100. We'll start to see leaf browning and now we got permanent leaf loss so that's the that's the danger that looms on this horizon. Here it's not lethal right now although we're having a little impact on plant height. It's going to be as if these temperatures increase then we're going to have growers have with some burning and that that you know yeah how do i stop that. I have no clue yeah right there out there with some air conditioners there's nothing we can do about that but we can advise them that they're not getting hurt right now that though that we can wait on the rain. Yes we're all concerned about it but as long as we keep these temperature but the moment those temperatures go up. Then we gotta tell these growers we got we got problems we're going to hurt this crop. So that's at V5-V7 have it smaller than that V2 and V3 it's not required very much water. It can tolerate a little more heat so it's a little better position for a longer stretch of dry weather so we're making roots right now. Let me turn to that topic there making is there anything I can do and that's a question I get. Anything I can do to grow these roots or improve root uh mass penetration well there's they're not a whole lot you can go ahead you know the key is nutrition. You know as long as the corn is getting plenty of p and k it's gonna be fine as far as growing tissue. Now there are some micronutrients associated with root one of them is boron. Boron is in the root tips of a corn plant and this is true of any plant boron is especially concentrated because it's imp influencing enzyme production of auxins and stuff like that and which helps the root grow root tip grow. And also helps it penetrate or the soil as it grows. So an application of boron some growers are doing that today i mean at planting time. Anyway these days but a small amount of boron foliar application can improve some root uh growth there yeah by providing plenty of boron. So in some cases while growers are making some lay-by applications and they're asking what they can do if they haven't applied boron and planting or they don't have a good feel for how much boron they have. Whether the little foliar application wouldn't hurt the plant we've seen benefits uh and yielded doing that up through v5 or v7, so that's a an option for those who just got to do something? Sometimes they just got to do something, so at any rate so there's a thing that I’ve talked to a number of folks and this really just pertains to the coastal plain. It's only for sandy soils and the coastal plain would not do this well and he played much other places that is ripping in the middle of the row. Is there any benefit and I’ve i've worked with a grower down in Greene county uh who I’ve seen do this over a couple of seasons and it does appear to have has crop or has appeared i say to help his crop. Now there's a caution here, first of all our indication the data and I showed this in some slides when I talked about root growth is we don't get a lot of root growth into the middle of these 30 36 inch rows. So you're not probably going to hurt or damage much of the root mass by doing this. However, if you're heaving up soil by trying to rip deep in the profile you're going to you're going to displace roots and have some impact. Furthermore you're digging up uh water and or soil that's got some moisture and exposing it to drying out at the surface. So where does this have a have a benefit with all those negatives? Where does it have a benefit? Well, if your top and this is where i see it in Greene County, if that top four inches of soil is hard as a brick it's compacted and we're getting these little and we've had them here last week at least across some of the state. These little quarter inch ,half inch rainfall events and your soil is compacted like that those are not infiltrating they're sitting on the top and evaporating. So by breaking up it, we used to do this with a cultivator um when we used to cultivate corn, you're breaking up that little that compaction there by ripping in the middle of the row. Now obviously you're not wanting to rip very deep to do that which is good, but you're just ripping enough to break up that surface hard pan and allow a little infiltration of small rainfall events. That's where it would have some benefit and that's where I think the grower in Greene county has found some benefit from doing that. I do not think deep ripping is helping get roots deeper. I don't think it's having much impact but I do think when he does that he has an impact of getting these smaller rainfall events into the soil. This is not something every grower will do it's only in isolated conditions or situations that i think it could have some positive benefit. So if your growers are asking about it, why I would make sure they are looking at how compacted that surface is with how much moisture they got below that compaction and see if they can't tickle that to allow some infiltration of small rainfall events. Again a a cultivator could have done this in the past. So anyway there's a couple of approaches right now on small corn that has that somebody who's worried about could think about. Whether it applies to them in most cases we're just going to have to sit tight understand what the where the problems are going to be as far as the impact on the yield potential of the crop and you know go to church whatever you have to do. Yeah so that's where we are right now understanding the impact on the crop and for certain growers they might have some benefit. So that's the comments that I have.
Once again that's comments from Dr Ron Heiniger regarding our corn situation, dry weather on small corn and maybe a couple strategies you can implement on your farm. if you like this podcast please subscribe and leave a 5 star review and as always thanks for listening to crop sense because if it isn't making money it isn't making sense you