We visit with Dr. Matthew Vann, N.C. State University Tobacco Specialist about how the Tobacco Season has gone so far. We also discuss what to expect with fertilization, weed control and diseases going forward with the dry weather. Please subscribe to the Crop Sense podcast to stay up to date on crop information.
We visit with Dr. Matthew Vann, N.C. State University Tobacco Specialist about how the Tobacco Season has gone so far. We also discuss what to expect with fertilization, weed control and diseases going forward with the dry weather. Please subscribe to the Crop Sense podcast to stay up to date on crop information.
Welcome to crop sense presented by North Carolina cooperative extension I’m Jacob Morgan, a field crops agent with NC Cooperative Extension. Today we have Dr Matthew Vann, North Carolina State University Assistant Professor and Tobacco Extension Specialist. Good Morning Dr Vann, tell us a little bit about yourself. Good morning Jacob thank you for the opportunity to be here today so my name is Matthew Vann, as you said and as you well know I’m the state tobacco agronomist and I have been in that position now for about five years. I was hired on after I finished my PhD in 2015. I was born and raised in the tobacco belt in north central Florida in the Swanee river valley. I grew up on a small family farm where we had had timber and beef cattle and did what I call a little bit of truck farming with you know selling some produce and vegetables throughout the summer but as a kid you know certainly working in agriculture in a small southern ag community tobacco was a big hub for what a lot of farmers and families relied on you know. In in my I guess of my generation and uh the first job i had quote unquote off the farm was driving a 140 farmall for a neighbor basically trucking tobacco to the barn. Going and selling tobacco with him once a week and I think that was kind of where I kind of got bit by the tobacco bug. So when I graduated high school you know went to college I graduated from the university of Florida in 2009 i had a degree in environmental management in ag and natural resources and then double minors in agronomy and soil science and as soon as I finished my undergrad.
I came straight to NC State and started uh working on a master's with Lorren fisher and David Smith focusing on potassium fertilizer application in flu cured tobacco. Finished that in 2011 and stayed for a PhD and started that again in 2011 and finished it in 2015. I really focused on some core questions with some crop rotation and how having tobacco in a cropping system, from a rotational standpoint, can help with weed management you know from a bigger multi-year perspective. So you know really the bulk of my education has been in agronomy and soil science and that's really sort of the heart of what I’m passionate about and really focusing on tobacco production. I come from a long line of tobacco farmers my father was a cooperative extension agent in north Florida and he just retired last November after i guess it was golly 30 years of service with Florida cooperative extension. So you know a large amount of that was helping Florida tobacco farmers. So again that's very near and dear to me and it's my honor and privilege every day to wake up and go to work to help North Carolina tobacco farmers be successful and sustainable in producing this this cash crop. So today is May 18 2021. tobacco transplanting is well underway and finished in some areas. We've got some growers that have been finished for a little while. Can you give us a quick rundown on how the tobacco season has gone so far. Sure so, you know unlike other crops, for those that listen and may not be familiar with how we produce tobacco seedlings. Unlike other crops you know corn, cotton, soybeans, peanuts, etc we don't direct seed tobacco into a production field. We start transplants in a modified hydroponic system, takes us about two months to grow transplants and then we take them to the field. Typically in eastern North Carolina that's going to start you know roughly the first or second week of April, depending on outside environmental conditions. In short we had a very good greenhouse production season. Again takes us about 60 days to grow transplants so somewhere around valentine's day we ramp up seeding greenhouses and getting that process started. Things went very smooth during the greenhouse season and it's my opinion that at least while I’ve been affiliated with NC extension this was one of the best greenhouse seasons we've ever had. Very little disease incidents other than some of our normal issues like black root rot and Pythium. Again we see that year in and year out but as a whole our transplant supply for the number of houses that were seeded and the number of commercial transplant producers we still have our supply was relatively good. The biggest issue we faced coming out of the transplant production season into the actual field season is a shortage of transplants. That sounds a little counterintuitive because as I just said we had one of the best greenhouse seasons that I can recall you know over the last probably eight to ten seasons. But it's important to remember that we are ramping up production of flu cure tobacco in North Carolina. This year we grew about 92,000 acres based off USDA estimates last year and current estimates at least from the numbers that I have and speaking with farmers and folks in industry, I think we'll probably have somewhere around 120 to 125,000 acres of flu cured tobacco this year. USDA numbers don't reflect that just yet it any matter I’m still thinking we're probably going to have a 20 to 30 percent increase in our production acreage and production volume. So when you have that kind of expansion in just one season inevitably there's going to be some shortcomings and i think that's where our really restricted really tight seedling supply is coming to bear fruit. Now so as you said we've been transplanting now since I’d say the first week of April so we're really looking at about a month to a month and a half out from that particularly as you look at some of the farms going into jones county and further places uh south and east in this state as a whole now that we have again really gone through the peak of transplanting season. We've got I guess the perspective to kind of look back and as good as our greenhouse season was our transplanting season has been has been really really difficult. We started transplanting season it seemed like we had some cool conditions and some places. We had you know some really damp soil conditions and then it was like a switch was flipped and our moisture became extremely deficient. You can even walk outside really in my mind for about the last month and we've not had much humidity to go with that. Our temperatures have fluctuated not quite as extreme as I’ve ever seen, but you know we've had days where we're at least in the triangle it's been 85 degrees or maybe a little bit warmer and then we've had days where we've had a couple of hard frosts and hard freezes within that four week period. So we had as late a frost as I can ever remember we had two consecutive nights here in the triangle where we hovered around 32 degrees towards the end of April. We came through that in a pretty good situation. But as I said, once that freeze and frost kind of lifted conditions really began to deteriorate even further. We've not had really any substantial rain to speak of you know over the last three to four weeks. In places there have been isolated showers where growers have had anywhere from two or three tenths of an inch to maybe seven or eight tenths. We'll take anything we can get at this point but we are really headed into a critical time where we just don't have a lot of soil moisture to help plants become established and really start to take root and take off like we would expect for a crop that's been in the ground for three to six weeks in a lot of places. So we've got growers now that where they can they're trying to irrigate and that's an unusual spot for us to be in at the end of April and early May. That's very uncommon for us so again I said that 2020 was one of the hardest growing seasons we ever had because of cool conditions and excessive rainfall and now we're really kind of in the opposite boat here in 2021. I may eat those words you know that I that I shared about 2020 at some point. So as you said it's been mighty dry so what effect has this weather had on maybe getting the crop established and also you know we put fertilizer out or how much do we put out. And weed control questions as far as getting stuff activated or better weed control/ worse weed control? How do you think that dry weather is going to play out. So you know again you can go wherever you want to in the state where we grow flue-cured tobacco and you're going to find dry conditions. In most places we're probably two to four inches behind where we should be for our seasonal rainfall to date. What that means from a fertility standpoint is that we may not wind up applying as much nitrogen to this crop as we would in a in a typical season. We did some work a few years ago where we looked at possibly scaling back some of our nitrogen application to account for dry growing seasons and what we found was that we could reduce our nitrogen output by about you know let's say by about 20 percent and still not have any kind of negative impact to yield or quality. If we're in a situation where our growers have good access to irrigation water, irrigation infrastructure and they can put some water out and do that very proactively as needed, then I think we need to stay the course and really focus on you know our target nitrogen applications that would follow a normal extension recommendation. But if we're dealing with growers that don't have that that option you know they may need to scale back some of that nitrogen just so we don't have it hanging around later in the growing season and really causing issues with greening and curing and those kind of things. So nitrogen would be the big one that I would focus on from that perspective. I would not get heavy-handed at this point. If we transition and talk about weed management you know as I’ve been in commercial fields and been in some of our research plots our weed pressure where we don't have irrigation going through the field has been almost non-existent, which is a great thing. We just don't have the soil moisture to get the tobacco crop established and we don't really have the soil moisture for the weeds to get established. A lot of our growers you know I would say that the bulk of the heavy lifting with a weed control program so herbicides in this conversation, you know all of most of our herbicide application is taking place before a plant even goes in the ground. So we're talking about pre-transplanting herbicide applications this is a year, where if a grower uses a pre plant incorporated method you know they've got some activation they've got things you know in the ground ready to go and they're doing their job. But if a grower has a pre-transplanting soil applied application that's not mechanically incorporated they really need to be out plowing this crop to get that herbicide activated and to let it do its thing. Particularly if they don't have irrigation, we talk about the need to get these materials activated in a timely manner and I think this is the exact situation that we worry about with those pre-t applications. So again we've not had a tremendous amount of weed pressure just yet we know the weeds are coming. It's going to rain at some point and if we don't have that herbicide activated or those herbicides activated we're really setting ourselves up for failure. So again we absolutely encourage growers as tempting as it is to delay a cultivation uh just because it's so dry and we worry about the soil drying out even further um or even you know some soil disturbance that could you know hinder the growth of some of these small very tender plants if it's been seven or ten days after you've transplanted and you hadn't done anything in that field i would strongly encourage a grower to get out and do a very light you know secondary cultivation application just to try to get some of these products activated if they weren't incorporated before planning. So again we're kind of staying the course on that we've not seen a lot of weed pressure but one of the things we talked about at our winter meetings this year was really pushing some of these lay by herbicide options for growers to strongly consider. This growing season we've got concern about weed seed contamination in flue-cured tobacco and in our exports. Just because weeds aren't there yet again as i said they're coming so we need to be proactive. These post-transplanting applications we need to be thinking about them as the season starts to creep on over the next couple of weeks minimal weed pressure now means that if we can get those products out and get them activated we're that much further ahead of the curve and things are going to hold up pretty well for us. So again we're going to stay the course on those as well. So it seemed like it rained all fall, all winter, and as we know the rain can wash that sulfur out of the root zone so is sulfur deficiency something you think we should be on the lookout, for should we just go ahead and try to correct it up front with our fertilizer applications, or do you think it's something that just kind of keep a wait and see? Yeah so I think that's a really good question. I was hearing some statistics from some of the weather services here and at one point we were we were on the borderline of having I think the wettest or the second most wettest winter on record here in North Carolina. Into your point it seemed like it rained every day and didn't stop so I think the sulfur question is absolutely you know a great one to ask. Sulfur is highly leachable. We think about sulfate having that that negative charge associated with it, our soil has a negative charge and you don't have the ability to have that binding access there. We're fortunate in tobacco that with sulfur that is an important nutrient, but we don't need any more than about 30 pounds per acre per season for maximized yield and quality. So one I think in the in the grand scheme of things tobacco's probably a lower consumer of sulfur probably relative to some of our other crops so that's a good thing number one. Number two, I typically find that we've got good residual sulfur or sulfate in some of our B horizons where we've got a subsoil that's fairly close to the to the soil surface. So if we're within about you know I’d say eight to ten inches of that b horizon we've probably got enough there we just have to get the roots down to it. To go with that most of our fertilizers that we're going to use for tobacco production have a good charge of sulfur in them. So I’m thinking about the two most common sources of potassium so we're talking about potassium sulfate and sulfate of potash magnesia so we're thinking about kmag in that scenario. Both of those have a good slug of sulfur in them and I argue all day long that when we target an appropriate potassium rate, so we're looking at somewhere probably in the ballpark about 125 to 150 pounds of k2o per acre, we're bringing more than enough sulfate with those nutrient sources those fertilizer sources in those systems. So you know we've kind of checked multiple boxes when we look at our fertilizer sources all of them are bringing sulfur with them. We still have a large number of growers that are using N-P-K homogenized or even some ammoniated fertilizers that have sulfur with them. Again we can check boxes there too make sure we've got enough and we also have some growers that are using liquid nitrogen. and I think about one that I use in my program a lot is 28% urea ammonium nitrate. I like it because it's liquid, it's got a small sulfur charge of about three percent with it. We've also got some growers that use ammonium sulfate in some other custom blends and it's got a charge of sulfur. So we got a lot of places where kind of no matter where we turn uh we got sulfur or sulfate coming to the table. So I’m not terribly concerned, I think there is a warranted idea that there could be some limitations particularly in some deep sands but my argument would be that if you have been you as a farmer have been maintaining the pH of those soils like we would recommend and you've been using dolomitic limestone, you should be bringing you know some of that to the table with you at the end of the day. So disease situation, I don't know about the whole state but Jones county, Craven, Duplin, tomato spotted wilt virus is a concern. Are there any concerns we should have as far as with the drier weather creating more of a disease problem or less of a disease problem. So that's a good question and with tomato spotted wilt, the dry weather we typically think about maybe exacerbating or aggravating some of those things. At the end of the day you know I’ve heard some entomologists say before that sometimes the thrips are like us. They don't like being out in the rain and you know they kind of get knocked off some of the vegetation when that happens. So I think that that could be a problem you know. But we also have to think about what was our tomato spotted wilt pressure last year? What were the thrips doing in the previous growing season and I don't particularly remember there being a widespread issue of spotted wilt virus you know in that regard. So again I don't necessarily know that it's going to be any worse than normal and i think because the heart of our winter was so wet maybe that's going to buy some time you know to go with that. If we think about disease management and black shank and Granville wilt, those two soil borne diseases being an issue that year in and year out or our number one and number two. I would probably have those a little bit higher on my concern list, but we typically see those aggravated by early season wet weather more so than early season dry weather and right now we're in such a dry spell that I don't know where that we're really setting ourselves up for great disease losses in those regards as we get into to late June and July, when we typically see them show up. So as I’m looking at things right now I hate to speculate too much but I’m not really you know getting out there on a limb and really predicting that we're going to have above average disease losses this year disease pressure. But again you know sometimes we think we've got things figured out with spotted wilt virus and lo and behold you know what we see in the field kind of bucks the trend as a whole. So it could happen but as of right now knock on wood I don't really see it being a major major major issue. Is there anything we didn't cover that you think would be worth noting for growers in the next three or four weeks. So let me go back and address one thing with the fertility so I got out on a limb and talked about dolomitic fertilizer. You know we're not we're not getting sulfur out of out of the dolomitic limestone we're getting magnesium and calcium. I guess one thing I want to elaborate on some of the conversations we have with growers when they try to decide on what potassium fertilizer source to use comparing sulfate of potash to sulfate of potash magnesia. One has magnesium, one doesn't, so a lot of times we tell our growers to make their decisions based off of what kind of dolomitic limestone they're using. When that happens they may or may not choose to use a supplemental fertilizer that has magnesium in it again like 0-0-22 or kmag and that may change some of the conversations about sulfur because inevitably one source of those potassium fertilizers has more sulfur in it than does the other. So again that that's kind of where the conversation about dolomitic limestone application comes into play and I just wanted to clarify that point that we're not necessarily focused on sulfur in that regard there's some other nutrients we're thinking about but to trickle down into some of our supplemental in-season fertilizer applications it could have some implications as far as decision-making. As always we appreciate your time Dr. Vann. Absolutely we'll push it out through our tobacco portal outlets and some of our social media pages so thanks for the opportunity to sit down and have a chat today. If you got a tobacco grower friend or neighbor share this podcast with them we'd appreciate it and as always thanks for listening to crop sense because if it isn't making money it isn't making cents.