 My name's Rebecca Faber, and I am a grad student at Michigan State, and this is my second time speaking in front of a lot of people, so just bear with me. So we have a problem, and what is that problem? Farmers have a very short window to plant their crops in the spring, and it is really risky to plant anything earlier than that. So some of the ways people have been solving these problems is using greenhouses, high tunnels. Those can have a lot of cost involved in those. And so we need to find a solution that included frost protection that wasn't super expensive. So this is just a graph of showing you that there's only 120 degree growing days in the Benton Harbor, Michigan. And so the solution we came up with is low tunnel. So what is a low tunnel? A low tunnel is a structure that's put over the crop row. It's got a bent piece of wire around it, and then there's a piece of plastic that's put over top of it. So why should we use low tunnels? Low tunnels lengthen the growing season. It protects your crops from wind and from cool temperatures. There's lower upfront costs, and I'll go into that as we go through. Compliments the field production system, so you're not getting a greenhouse, you're not using a high tunnel. It just compliments what you're already doing in the field. It allows you to plant and harvest crops sooner, and then it also lets you get the higher market prices at the beginning of the season. So here's a picture of my study. We did five different combinations, well four different combinations of plastic, and then we had an open treatment. Here's an example of what the cross section of each tunnel would look like. We had the dual layer system, which had a row cover plus plastic, then we had just the plastic, and then we had the open treatment. Each of those had different sensors in them to tell me the air temperature and soil temperature. We used two different colored plastics. We used clear and white. The two field crops we used were mountain spring tomatoes, which is a determinate variety, and then speedway cucumbers, which is a slicing cucumber. So here's our planting dates. We're planting the end of April. So in a normal year, you would plant the end of May if you were doing a normal planting. So some logistics, as you would think, the clear plastic provides the best transmission compared to the white. So we had two frost events in 2011, and as you can see, the two highest bars in the, I believe it's purple, and then the blue there had the best frost protection, which was the dual layer system, and it provided between three and seven degrees of frost protection. That dual system also provided double of the amount of degree growing days compared to the normal planting without a cover on it. So here's an example of what the no treatment, or no cover treatment looked like. It had windburn, it had frost damage on it. Here's an example of what it looked like under a clear single layer treatment. A lot more mature, a lot bigger. So here's your side-by-side comparison of what the clear dual layer system and the no cover early planting date looked like. You can see that there's a big difference. You got some of the plants in the front that were frost damaged, and then the plants in the back are the ones that were covered. Here's the cucumber comparison with the no cover and then the clear single layer system. All right, so in summary of the planting and harvest dates, we planted everything, as I said, early April. We harvested July 19th and July 20th, or July 12th for the tomatoes. And then for the no cover treatments, which were planted the end of May, we harvest those August 1st and July 23rd, which was the third harvest date for those low tunnel treatments. Here is a graph of the tomato yield. You can see that the clear tunnels had the most yield. The orange, the one on the very bottom, was that the no cover treatment, which started about two weeks later than the cover treatments, and as I said, had the lower yield there. Here's the data for 2012. Once again, we had two weeks earlier harvest, but then at the end of the season, we did have the normal actually catch up and yield cucumbers. For the cucumbers we planted in the end of April, they had the first harvest date for those were June 27th and the 25th, both for those in 2011 and 2012. The no cover treatments were planted, as I said, the end of May. The first harvest date for those were July 14th and 9th, so once again, two weeks difference in harvesting, and the difference that that was, so the low tunnel treatments had were harvested six times or five times before the actual no cover planting, which was in May. Here's the yield data for that. Once again, the dual ear system showed had the most yield, so I talked a little bit about how there's higher market prices at the beginning of the season because everybody else in the middle of the season is harvesting, so the price goes down. There's a $5 drop July 11th when everybody started harvesting their cucumbers, so our ideal harvesting time would be on this end where the price is $5 tired. Tomatoes, they're not quite as a big jump, but where that red line is, we weren't receiving any Michigan tomatoes before that. All our tomatoes were coming from California, Mexico, so our goal was to bring in tomatoes before we had to import those during that time. So the costs. So the cost per acre, this was a partial analysis, so we just started the no cover treatments at zero, and then we had the different costs, so we had the labor costs, which would be installing and uninstalling, and then we had the plastic and the wire and then the row cover. And as you can see, per acre, it ranged between $549 to $694, depending on what plastic. C stands for clear, and then W stands for white, so the white plastic does cost more, but I'll tell you that the clear is the best, the most beneficial. So some assumptions we made on our costs. We had a low ton of layer. That low tunnel layer is $3,500. If you were to assume that you're gonna use that for five years on 100 acres, it's approximately $7 per acre. You don't have to have a low tunnel layer to lay this plastic. You can lay it by hand, so that would eliminate that cost. The wires, we used over a five year period, and then once again I just wanna say that all the input costs are not included in this. It's just whatever the low tunnels would be extra. So here's the net revenue per acre, and you can see the two bars on the far right and the far left of each crop are the open treatments, and everything in the middle is the low tunnels, so as long as you are above the open treatments, which you are, you made a profit. So in summary, the best frost protection in the most growing degree days would be the clear dual layer treatment. That's the one that had the clear plastic and the roll cover in it. The best yield and revenue for the cucumbers was the clear dual layer treatment for 2011, and then the best yield revenue for the tomatoes was the clear single layer treatment, but based on the growing degree days and the frost protection, I would still go with the dual layer system. I have a lot of acknowledgments, specifically there for funding part of my grad student project, and then also I had a farmer, Pigit and Grills Farm is the farmer that actually helps, and this is his system. I also want to thank all my professors, Matthew, Ron, and Jeff for all their help and input, and I'm sure you have lots and lots of questions, so this would be the time to ask them. Just because I can see through that. What are you concerned with? How do you get the system shut off like that? Is that air is moving through it? So was that a challenge for you? Like if you had the courage to call my daughter, now you feel used to the curve. We did have some, yeah. He was asking if there's any disease issues with the lack of air going through it. There is a potential, but there are also, it's perforated. So there is some air movement, but there is a possibility of some type of disease. Yes. When you laid the plastic and your roll cover, which did you put on first, the perforated plastic? The roll cover goes on, well, the machine that I was using lays it simultaneously. They have, so the roll cover, the material portion is underneath the plastic. And, What is the revolving? Right. Right, so you've got your, if you can see in the picture, this is the metal wire there, and then the plastic and the roll cover are going over top of the hoops. The question was about drip tape, and yes, there is drip tape underneath the plastic. There is not any, so there was a question about heat, and there is no extra heat. It's all solar. No, but it overheat. There is a potential for that, but we didn't have any issues with that. We still had an earlier harvest, and as you could see, the yields were still at the same level as everything else. Yeah. Would you ever think about maybe doing this on the tail end of your season with the cucumber production? I would, the question was about cucumber production and later in the season, and yes, the farmer does do that with that. The only thing, let's say if you were going to do tomatoes, it would be difficult just because they're such a long-seasoned crop. When did you take the covers off? A month later. The covers, so she asked when were the covers removed? They were removed at the same time the normal planting date would have been, so the end of May. So a continuation of what was the temperature difference in the harvest, what they thought, was that they were starting in terms of highs and lows. So the question was about highs and lows of temperature. What, I guess my, what do you mean? That was at average temperature, 85 degrees. As a high, you took them off. Therefore, you felt that it was necessary to remove the plastic, or was the temperature lower than that, and what point did you decide that you needed to take the plastic off so that it wouldn't damage the plants? Okay, so the question is when to remove the plastic. And the reason, and so we removed the plastic because of, first off, the plant got at the top of the thing and it was coming out anyway. The other thing is at the end of May for us, there's no danger across. So pretty much you want to take them off when there is no more danger across. If you don't have a drope tape in this, it's a, or a garden, it's a 40 feet long roof system. There's condensation from the covering, and now it's watered. We have, if we have plastic over it, or we're gonna pull it up and water it. Question is about watering without drip irrigation, and I don't know the answer to that. Do you guys remove the covers during the day then, or did you keep them on all the facts? Like not a warm day when it was like 50 degrees and you remove the plastic and get more sun? So the question is about removing the tunnels. They're not removable. Once they're, once it's there, it's there to, to make sure that the plant got acclimated. We did cut them open at the top so that there was a little bit of an acclimation period. So we can't reuse the plastic. It's pretty much the same as using like plastic mulch. Weight of your road cover, and when we use road cover, look at it down the side staples, we won't actually, you had the edges buried, didn't you? We had so much wind that every time we tried to use the low tunnel, we got stuff to go in the lowest place. So it was the first question. The weights of the road cover, because we have different weights on the bottom. I'm not entirely sure what the weight of the road cover was. Do you get different temperature savings depending on the weight and the hole? I believe all I know is that the, I know the term transmission was 70, but it's something that's imported from Italy. So I don't have the answer to that. Is the only reason to not reuse the plastic a matter of the use of machinery or the floors or something else? Well, so the question is why we don't reuse the plastic. You, so the reason why we didn't reuse the plastic is because the farmer that was helping us with it, they would just cut it and recycle it, basically. I think you probably could unearth it, but you would have to find a way to rewind it up and then put it back on. It's machine. Right. Right. So by hand it would be different. Right. So if it, so by hands, if you were putting it down, you could take it back up, roll it back up and then use it the next time. Yes. So it's your own and trying to shop on that one? Yeah. I guess it depends on how you want to do it. If you're using it by machine, it's not beneficial. Yeah. Maybe some of us are on a scale where a machine, a liability, you know. So you're saying that the plastic hole that you got was made by fermentally? So there's, so the row cover material, which was the, it actually feels like a, like a cheap cloth or, you know, it's a material, that's fermentally. But I know that it's something that you could get here too. It's like a woven or spun? It will, yep, spun bound. With a permeation for water in the air? Yep. Okay. That's the box. That's the underside, yes. So that's, so the dual layer system, there's the, there's the row cover. And then right on top of that is the plastic. And the plastic is from here or from here? The plastic is from here. Okay. So the row cover's free to fall on? Both, both of them are. So the question was about breathability. And yes, the row cover is a material that's spun bound. And then over top of it is the plastic and that's perforated. So. Can you understand me correctly that the row cover is on hoops also? It is on hoops, yes. How much distance between the row cover and the plastic? There's, there is. The right on each? They're right on each. So the question is, is the plastic and the row cover right on top of each? Yes, they're layered together. Although maybe Jaria will be depending on the wind and the heat and cooling because I imagine that they can be unevenly stick together and maybe separate a little bit. I mean, there's a potential for a variable airspace or lack of it in there. How many does the state constant side by side or does it? So the question was asked about the difference in between the two different, the plastic and the row cover. And it's just draped underneath it. I didn't do any mud or anything to it, so. So if we did two hoops and used the same amount of cover material, would it potentially increase our ability to hold the heat? She said the plastic is perforated also. Yes, the plastic is perforated. You tell us how long the wires are and how far apart they are from the system. The wires, I believe, are two to three. It was every other plant. That's, I'll just go with that. It was every other plant. And we had 20 inch spacing on these. I don't remember what the length of the wires are, but it is in my report. So. How wide are the beds? They're five foot, so the beds are five foot centered. Five foot centered and it's in that. And then they range, I think that's about two and a half feet. So that's the trot. Where is the five feet? From center of one bed to the other is five foot. Yes, in the back. Did you remove those rope covers at the same time? Did. The double-layer and rope covers, did you remove the layers at the same time? So the question is, did I remove the dual system at the same time? And the answer is yes, we removed everything at the exact same time. Did you control the line? The question was asked about the black plastic and yes, the plastic mulch was for wheat control. Is there any other questions? Yeah. Have you ever seen any time that it was actually crossed on the seal that the plastic was actually crossing inside the floor? The answer to that question is yes. In 2012, which I didn't show in this specific presentation is yes. So let's say the air temperature outside was higher than the temperature inside the tunnels and we're still investigating why that was. And that's why I didn't show all my 2012 data because I didn't have an answer for that yet. Because I had that happen for a minute. There was water gross on the inside of the plastic, but the outside plants and stuff. And on that note, the other thing is the dual-layer system wasn't as cold, so the dual-layer system seemed to help with that, but the temperature outside was still cooler than it was inside. I have a partial explanation for that. You had a temperature increase without sun. That is, we had an overcast day. It was 40 degrees warmer than the previous day. That would do it because you wouldn't have the solar game. It was like at night, you'd have more radiation. More warm stuff at night. Yeah. The car crossed inside of the car. We told her that the outside of the can was cold. Yeah, we sometimes have that happen. It's frosty when we go to bed and 50 degrees when we wake up. You know, that kind of frost inside of the car. No solar game. Yeah. Yeah. Yeah. Related to that, I think that I asked somebody before. I had the same issue in my row cover. It's a big one. It's not a small one. But it's because the guy explained to me is that your row house keeps the moisture for the night, so it would be too completely colder at night. Attention, please. Workshop session two is now ending. And today's workshop is over. I've gotten a couple of different explanations. And I haven't really figured out which one. Leaders protecting nature and creating social change with organic farmer action.