Managing Stored Grains  - Scott Sanford is a distinguished Outreach Specialist with the Extension Ag, Engineering at the UW-Wisconsin, in the Biological Systems Engineering. Scott is a lead rural energy program person, and they look at ways to reduce energy usage, increase energy utilization and agricultural enterprises, and produce renewable energy. So, Scott has had a very diverse background. He came out of the Hudson Valley of New York. Grew up there. Got a bachelor's degree and a master's degree from Cornell University, and then spent 17 years in the dairy equipment industry. So, he worked for a number of different dairy equipment companies in private sector, and is now involved, has been at the UW-Madison since 2002, and works in many aspects of agriculture: working the energy side, working with dairy farmers and renewable fuels, and most recently, has been on the board for the Wisconsin Farm Technology Days. Please welcome Scott, Scott Sanford, thank you. (audience applauds)  - Morning. So, my task this morning is we're gonna talk about managing grain and storage. 

I'm gonna talk about the mechanical side, and PJ, who's gonna follow me, is gonna talk about the buggy side.  I thought that'd get a rise. Anyway...  So with storage there's...  six things that can cause problems in storage. The first is having too many fines and foreign matter, so, when you put it in I always recommend screening, and we'll talk a little more about that. The other is too warm. We've gotta keep it within a few degrees of the outdoor temperature. One, so it doesn't sweat, but also the colder we can get it the longer it'll last. Too wet. 

If we get too wet, that's obvious, we're gonna get heating. Uneven grain temperatures.  You can get convection currents within the grain bin, which can lead to problems in there.  And then the storage not cleaned, and this is where the buggy part comes in. We need to sanitize that, or clean that, between grain crops, basically to reduce our load. And then the other is just not checking the grain often enough. If we check it, we can find out problems, we can mitigate 'em. But if we never look at it, then you're not gonna know that you have a problem. So, the first is too much foreign matter. So, I recommend screening before you dry it. 

So, screening it before you put it in. A lot of people don't do that. It's hard to separate out the bee's wings, 'cause they kinda stick to the corn, but if you can get as much as you can out, that can be very helpful. Then, the other would be, if you're using a separate dryer from your bin, to screen it before you put it into storage. And a lot of people do that. Because the fines are what attract, one, it reduces airflow, but it's also the place where the bugs, if you got cracked kernels and stuff, some bugs can't get through the endosperm... of the corn unless it's cracked. So, you can starve 'em if you don't have as many fines, and PJ will talk more about that. Now, on the other hand, what we can do is put a spreader in there to spread the fines out evenly. That way the airflow is not impeded in one spot, because if we get one spot that doesn't get the airflow, that's usually where the problems are gonna be. 

So, it has to do with airflow also, as well as basically getting the foreign matter out of there. Grain too warm. We'd really like it to be within 10 to 15 degrees of the average outdoor temperature. And this is basically so it doesn't sweat, especially on the walls of the bin. And that's tough some days.  And that's the average daily temperature, not the peaks and valleys. But try to get it close to that, and so you gotta look at the forecasts and kinda plan ahead. For summer storage in the Upper Midwest we'd like to keep it at 50 degrees, and that can be tough. If you're gonna keep it through the summer you may have to do some nighttime aeration, when the air is colder. Southern US, we can go a little higher, basically 'cause we're not gonna be able to keep it that cool. 

 For wintertime, depending on where you are in Wisconsin, basically if you can get it down around freezing that's optimal. With December this year that was maybe a little tougher than a normal year. But, trying to get the temperature down. And we usually do that in steps. So here's kind of a pictorial of what the suggested wintertime temperatures are, depending on where you are in the Upper Midwest.  To do that temperature we can use probes. So this is a manual probe, you can walk out an push into the grain. They come in different lengths. The other is to put a temperature cable in there, so you can see the grain at different levels in the bin, versus just the top, whatever you can reach.  One of the issues here is: To find a problem it can be only a couple degrees difference that you may see, between every two weeks or every month, temperature change that may indicate a problem. 

'Cause one of the problems is corn doesn't conduct heat very well.  So, your problem if it's away from that sensor, it may be only a few degrees temperature difference over time that may indicate a problem.  So, typically what you're gonna do is, you need to keep track of your data. On a month, every time you go out and measure that, you keep track of your data, and look for changes.  And this top one, seven and eight aren't in the grain, they're above the grain level, but you can see on the second one I've got the red marks. The five six, or, four, five, and six. That indicates that a...  a case where we've got some rising temperatures. And you can see, they're subtle, but that would indicate that we've got a hot-spot in there someplace.  So if we have a hot-spot we need to aerate to try to mitigate that. 

 The maximum grain temperature, or grain moisture percentage, recommended for grains will depend on how long you're gonna keep it. And you have to think about the end user, not just you. You may only be keeping it for six months, but if the next guy's gonna keep it for another six months, you gotta look at that to figure out where you need to put it. So, typically with corn, if we get it down to 15%, that's up to six months, so if we sell it by May, May or June, if we're gonna keep it past that, we need to get that down to 14% when we put it in storage. And if we're gonna keep it longer than that, we wanna bring it down to 13%.  And that gives some safety factor to make it last.  So, I talked about uneven grain temperatures, convection currents. You can get those, 'cause we got cooling on the outside, so you get airflows in the grain.  And what'll happen is we'll get this temperature rise through the middle of the grain, and we'll get a moisture accumulation right in the center, that's on the top, and that's usually where you have the problem if you're gonna have a problem. 'Cause that's usually where a lot of the fines are as well. 

So this is one reason we want to try to get rid of those fines. And another way to get rid of the fines is to core it out. So, after you fill the bin you core it out. You take some grain out and you could...  screen that and put it back in a bin or use it.  But that can be another problem, the cool temperatures. Especially, we're having really cold now, it's gonna get warm the next couple days, and then it's gonna cool down again. So all that kind of weather will cause some convection currents within the grain.  So aeration is the...  best method to solve some of these problems. 

And, basically we want a level surface on the top of the grain. If we don't have a level surface we're gonna get shortcutting. So, if you've got high in the middle and low in the sides you're gonna get more airflow through the grain, the low part of the pack than the high part of the pack.  Aeration...  The rate, or the cfm per bushel is gonna dictate how fast you can cool the grain. More is usually better. So you can take advantage of cool nights, for instance. So, here's an example. If we've got 0.05 cfm's per bushel it's gonna take us 208 hours versus 140 if we double that. Typically to get the cooling front, or warming front, depending on what time of year it is, to go through the grain. 

Typically we're recommending 0.1, but a little higher wouldn't be bad either.  And as I said, higher airflow rates can take advantage of short term cold temperatures.  The other recommendation is to cover the fans to keep rodents out, and it'll reduce convection currents within the grain. So they do make covers that you can put over, or you can make your own, just a plastic sheet, with some kind of band around the outside, to cover that up.  So, when you go to change a temperature, you're gonna start the air, and you're gonna get a cooling front that's gonna go up through that grain pack. And it doesn't matter which way your fan is, some are negative pressure some are positive pressure, but it's gonna push the air through that, so that air front's either gonna come up or down, depending on which way your airflow is.  So this is gonna be a typical setting from the fall, so you're gonna dry this or cool this corn down in steps.  So this is showing 150 hours to cool the grains. You're gonna come down in steps as you get down, and when you get down to December it should be cool, hopefully we had cooler weather than this year. you'll get it down and cool it, and then it'll basically maintain it through the winter. 

 So, here it is, looking at how it affects the bug issues.  So, and I'm sure PJ is gonna dwell on this some more, but when we get above 70, we're optimal for insects, molds, and spoilage. If we get it down below 70, you reduce insect reproduction. Below 50, insects start to go dormant. And if we get down to around the 32 degree mark, basically most insects won't last through the winter there.  PJ's gonna go through this a little more, but it's important that we clean out the bins. Basically to...  try not to reinfect the bins.  Temperature controls and fans. There are all kinds of computerized controls, or you can do manually. 

We can have thermostats with...  Well, one thing I recommend is you put an hour meter on your fans, so you know how many hours it's run. That'll give you better feedback on how long it's run and where the cooling front might be in your grain pack. They also have computerized controls that'll look at the temperature and stuff, and the humidity, and turn the fans on when it's optimal for cooling. Or, if you're trying to dry something, that'd be the other thing, if you're trying to take some moisture out. And they have systems that'll control multiple bins and stuff. So, that's another example of technology you can use to make your job easier. So here's kind of a checklist: Warm weather, we want to check it every one to two weeks, and cold weather every three to four weeks. Want to turn the aeration fans on. Ensure they're running properly, ensure we got static pressure. 

You should have a static pressure gauge someplace in the system, so you can make sure you're getting good airflow and there's no shortcuts. Climb up and look inside the bin. Are we getting condensation under the roof? Wet, we have snow cover. If you got some snow in there you may have to run the fans to drive off that snow. Check for odors. That's an indication of mold or spoilage. Look for crusting.  And measure the temperature at several locations, if you don't have the temperature cables. Look for signs of insect activity. Log things. 

You might remember there are bugs in there, but did that happen a week ago, two weeks ago,  or six weeks ago?  Things have a way of escaping us as far as time, so, recording that's good. And then you can compare, it allows you to compare readings and findings from this year, but also in successive years as well. And then take any corrective action and then record that as well, so you know what you did to solve the problem, and indicate whether it actually solved it.  Here's a new technology that's out there, I thought I'd throw a slide in for this. It's using ozone for grain treatment. Ozone is a great use for killing things, basically oxidizes things. So, that's a technology that is kinda new in the market. It doesn't have residual base, but it can help.  I know the potato growers are using it in potatoes. We use it in hot tubs, we use it in... 

I think the organic growers can use ozone for...  purifying water.  So it's a great option.  But probably not cheap.  So yeah, it can kill bacteria, or insects, we don't worry about bacteria. It claims to be able to reduce microtoxin levels, stop mold growth,  but it won't stop heating. Basically, that's usually a moisture issue. The other thing I want to remind people is safety. We have people get killed in bins every year, because they don't adhere to safety protocols. Basically lock out your controls before you go in, so nobody can start it while you're in there. 

 If you've already cored out and stuff, be aware there could be cavities that you could fall into. It's recommended use a harness and a respirator, in case there's mold in there.  And if you have to go in, make sure you got somebody else there. And let me point out, tying a rope on you, and having somebody tying it to the edge isn't gonna help. All it's gonna do is help the rescuers find out, they can follow the rope to you. You need a harness with something that's gonna hold you up if...  what you're walking on collapses underneath your feet.  So here are some resources. One of the best resources is this, Managing Dry Grain in Storage. It's a Midwest Plan Service publication. 

And then they have a series of others, but that one specifically covers what we covered today. And there's a few others on here that I put, and I think they're in the publication as well. And here's some stuff about the ozone treatment, so some of the papers that are out there that you might refer if you wanna read some more on that topic.  So, with that.  We have any questions? (audience applauds)