(Jim) Good morning folks, welcome to That’s My Farm. I’m Jim Shroyer, your host. And we’re in luck because we’re on the Agronomy Farm here on the K-State campus. And we’re also in luck because we have our environmental quality specialist, Dr. Peter Tomlinson and Peter’s going to be coming on the show here in just a second talking to us about what’s in the soil, and why it’s important. So, get your cup of coffee, hurry on back, so we can start the show.
Closed Captioning Brought to you by the Kansas Soybean Commission. The Soybean Checkoff, Progress Powered by Kansas Farmers.
(Jim) Good morning folks, welcome to That’s My Farm, I’m Jim Shroyer your host. And we’re in luck because we have Dr. Peter Tomlinson, our Environmental Quality Specialist here at K-State. Going to talk to us today about soil microbiology, soil biology and I know you’re sitting there thinking, He’s gonna do what? Yes, we’re gonna be talking about critters in the soil. So Peter, thanks for being on the show. (Peter) Thank you Jim, for the opportunity. (Jim) So, kind of regale me here. (Peter) Yes, so below our feet when we’re standing on the soil, there are a wealth of organisms in that soil. In one teaspoon of soil, we can have hundreds, hundreds of thousands to billions of organisms in that one teaspoon of soil. We can have tens to hundreds in an agricultural field. Anywhere from hundreds to tens of hundreds of yards of fungal hyphae. Earthworms, nematodes, all sorts of organisms live in our soil. (Jim) Don’t forget gophers. (Peter) We’ve got gophers. Don’t fit into the microbial and the size fraction that I tend to think about in the soil, but certainly gophers do change our soil. When we think about an earthworm for example and we think of them as Mother Nature’s rototiller. They are constantly moving through the soil, mixing the soil, breaking down our plant residue in terms of the size of the pieces of plant residue. They create an environment that is… (Jim) A healthy one. (Peter) A healthy environment that promotes bacterial and fungal growth as well as the growth of many other organisms that live in the soil. So, really, having a good understanding of what’s happening in terms of soil ecology and how our farming practices both benefit and potentially harm our soils is important. And looking for opportunities to make the soil a healthy environment for our soil organisms, certainly our growing plants are an important piece of that. The plant roots produce carbon compounds, or release carbon compounds and sugars that are a great food source for fungi and bacteria and they… but if we think about our growing crops, they’re only on the field for a short period of time. And so one of the things that the practice that is coming into favor is cover crops and keeping living roots in our soil system, in our cropping systems, for the entire growing season, if that’s at all possible. (Jim) Peter I’m going to have to stop you here, we’ve gotta take a break. Folks, stay with us. Get your cup of coffee, come on back, after these words from our sponsors.
(Jim) Welcome back to That’s My Farm. I’m Jim Shroyer, your host. And with us we have Dr. Peter Tomlinson, our Environmental Quality Specialist. And Peter thanks for staying with us during that commercial break. And Peter we’re standing in a no till field here. We’ve got soybeans growing into some corn stalks, and across the way we’ve got a little more clean soil over here, clean till, not quite clean till, but you know, that’s been one of the big things, not only water conservation with no till, but we’re talking about soil health as well. And we alluded to the earthworms a second ago but kind of carry the conversation a little bit further about the old system of clean till versus no till. (Peter) Right. And so as we compare the two systems certainly there are some challenges. There…with a system that relies…clean till system certainly one of the areas that I work in is water quality and there’s certainly a lot of concern across the state about sediment transport to our lakes and reservoirs. (Jim) Nutrients going with it. (Peter) Nutrients going with that sediment, nitrogen and phosphorus runoff from those systems. And so there are a number of management structures- terraces, grass waterways, buffer strips that we can put in place. But one of the ways that we can quickly change the amount of loss of soil and nutrients from our agricultural systems is transitioning to no till where we don’t have tillage implements going through the field. We’re leaving that plant residue on the surface and we’re relying on the soil biology to perform that tillage operation. (Jim) So to speak. (Peter) So to speak. (Jim) Yea, cause some fields have a boat load of residue. (Peter) They do. (Jim) A couple hundred bushel of corn crop has quite a bit of residue. (Peter) And it will take time for that residue to break down. We’ve got organisms in the soil that their job is to shred plant material, tear it apart, break it into smaller pieces. And then that’s followed by our colonizing organisms, our bacteria and fungi that are going to grow on those smaller pieces of residue. There’s more surface area for them to grow on and they’re going to be breaking down the chemical compounds in that residue. (Jim) I was gonna say, what’s in it for them? (Peter) Well, there’s food in there. There’s nitrogen, there’s phosphorus, there’s potassium that they need as well as micro and macro nutrients and amino acids, that the organisms need to grow. And you know as they grow and die, there’s a whole other group of organisms that come into play, our consumers. And this does include nematodes, mites, protozoa, that are feeding on the bacteria and fungi and as they eat those the bacteria and fungi they’re taking in the nutrients that the bacteria and fungi got from the plant and they’re incorporating some of those nutrients into their body for their growth. But they’re also excreting plant available nutrients that can be taken up by the growing plant. Or they themselves will die, be consumed by bacteria and the cycle begins to repeat. (Jim) Peter hang on here. My camera man’s telling me we gotta take a break. Folks, grab a cup of coffee. Come on back. We’ll go again on the show.
(Jim) Welcome back to That’s My Farm. I’m Jim Shroyer. It’s good to see you’ve got a cup of coffee in your hand there. And with us we still have Peter Tomlinson, he didn’t run off. It’s twice now you didn’t run off during the break. Peter, you know a lot of times I think of microorganisms, microbes in the soil, I think of as bad. I think bad things about ’em. But like you said just a second ago, they’re very important and one in particular is mycorrhizae. (Jim) Mycorrhizae. (Peter) Mycorrhizae, it’s a group of fungi that grow in association in a beneficial relationship with our plant roots. We can find them in soybeans and corn and some of our… (Jim) Now you’re not talking about, I’m thinking a symbiotic relation, you’re not talking about bacteria for the legumes. We’ll talk about that in a second. (Peter) No, we will talk about that after the next break. We are talking about the mycorrhizae fungi that play a very important role in helping the plant meet their phosphorus and potassium needs as well as in times of moisture stress helping them meet their water demands. (Jim) OK. Obvious question is how do they do that? (Peter) How do they do that? (Jim) That’s a lob to ya. (Peter) Yes, so in terms of a soybean the mycorrhizae that infect those roots are arbuscular mycorrhizae, vascular are arbuscular mycorrhizae and they infect the root, they grow in the root, and then their fungal hyphae, the fine hairs of the fungi extend out and so… (Jim) Through the root. (Peter) Through the root out into the soil, and so where the root is only accessing a very small part of the soil the fungi can increase the amount of contact, effective contact that the plant root is having from 100 to 1,000 times. So the surface area that they’re able to pull in phosphorus and potassium is greatly increased. And in exchange for those nutrients the plant is providing the food that the fungi needs to grow in terms of… (Jim) The photosynthates, the sugars. (Peter) The sugars, carbon rich compounds the fungi need to grow. And we can find mycorrhizae not only in our agronomic crops, but they play a very important role in our pine forests across the country as well as many other plants. (Jim) It’s big in corn so corn, obviously corn and soybeans. I know there was a researcher here a few years back that was working on wheat mycorrhizae. (Peter) Yep, there is some new research that is being done here right now at K-State looking at mycorrhizae inoculums and wheat. And we’ve…there’s just a lot that we don’t know about this very important plant microbe relationship. (Jim) That’s a good… one of the good guys, good gals. (Peter) Yes, it is. (Jim) Peter I gotta take a break here. Folks, stay with us. We’ll be right back after these words from our sponsors.
(Jim) Welcome back to That’s My Farm. I’m Jim Shroyer. We have Dr. Peter Tomlinson with us, our Environmental Quality Specialist and we’ve talked a little bit about good organisms, mycorrhizae, we just mentioned that a second ago. We’ve got an example of another one here that we all know about and that’s with soybeans. (Peter) Yes, here we have an example of rhizobium bacteria that forms a nodule on the root of soybeans. In fact our farmers across the state will add inoculum, which is basically it’s… (Jim) A live. (Peter) A live dose of this very beneficial bacteria to make sure that their soybeans are going to nodulate. One of the challenges that we’ve seen so far this year is with the cool, wet soils. We’ve been seeing some signs of nitrogen deficiency in our soybeans. And nodulation in many areas across the state has been slow so far. (Jim) That’s because of the saturated soils. (Peter) The saturated soil, low oxygen levels and cool soils. The nodule creates an oxygen free environment that’s important for the function of the bacteria and the biochemical processes that are occurring within that. And the red color that we see in those nodules if you slice ’em open, it’s a good sign, a good indicator that the nodules are functioning and active. (Jim) Fixing nitrogen. (Peter) Fixing nitrogen. And the compound in there is called leghemoglobin, similar in characteristics to our own hemoglobin that helps with oxygen transport. And plays an important role in the overall chemical reactions that are occurring within that nodule. (Jim) Peter thank you for telling us about rhizobium and their interaction with soybeans. And folks, come on back after these words from our sponsors.
(Jim) Welcome back to That’s My Farm. I’m Jim Shroyer, with us we have Dr. Peter Tomlinson. And you know Peter, we talked a little bit about earthworms early on and I know that you have a passion for earthworms and not from a fishing standpoint. I know putting ’em on the hook and get a lot of perks that way and some fish. But that’s how I like to use ’em- earthworms. But Peter, talk to us a little bit about earthworms. They are not respected as much as they should be. (Peter) That’s right Jim. Earthworms are a very important piece in our soil ecosystem, a very important piece of the biological community. And they are under respected. And what I’d like to share with your viewers this morning is that we have a wide range of earthworms that we can find in Kansas. And not all earthworms are the same. We have many different species of earthworms that live and do their job in different parts of the soil. So, we have a group of earthworms that are classified as epigeic earthworms. And this group is the worms that we’ll find in the litter layer, the thick litter layer within a forest and sometimes in our prairie system. The next group is our endogeic earthworms. And this group of earthworms we tend to find within the soil profile. (Jim) You’re talking about the upper three or four inches, or you talking several feet? (Peter) It can be the upper, primarily in the upper foot, is where we’ll find them. They’re consumed… (Jim) Those are the good ones for fishing. (Peter) Well, we’ll get to the good ones for fishing in a minute. (Jim) OK. (Peter) This group will feed on decaying roots and other organic matter that’s already been brought down into the soil profile. And the final group is our anecic earthworm. The classic example of an anecic earthworm would be the night crawler, or in technical terms lumbricus terrestris. (Jim) OK, I’ll pass on that one, but OK. (Peter) And this earthworm forms a permanent or semi-permanent burrow. It’s the one that will come to the surface and actually tear apart pieces of plant leaves and pull them back down into their burrow. If you find a burrow and you break it apart carefully there’s times that you’ll actually find the inside of that burrow lined with plant leaves. And part of that is that their coating that with soil and mucus and basically creating an environment for bacterial and fungal growth so that that leaf begins to break down and becomes a better source of food for them. The waste that’s excreted is rich in nitrogen, potassium, and calcium magnesium and many other nutrients that are needed. (Jim) Important for the plant. (Peter) For plant growth. (Jim) Let’s get to the fishing ones. (Peter) So you know, from a fishing standpoint lumbricus terrestris or night crawler is a good fishing worm. We’ll share today that it’s important that we are careful with our bait worms. There have been a number of instances across the U.S. where throwing the bait worm on the side of a stream or lake has actually led to the introduction of an earthworm that’s not native to that area. And we’ve actually seen some significant changes in the amount of… (Jim) Population? (Peter) …well the amount of organic matter and the cover on that soil. And so we’ve actually seen some cases where we’re seeing more erosion that is having a negative impact on the fish habitat in those streams. Just be cautious with your worms when you go fishing. Use ’em, but take ’em back home with you and put ’em back in your garden where you dug ’em out of. (Jim) Peter I really appreciate you taking this time to talk about the various soil microbes and your passion for earthworms. (Peter) Thank you Jim. (Jim) Folks thanks, for being with us on the show. And don’t forget next week about this same time, we’re gonna have another show of That’s My Farm. See you then.
Closed Captioning Brought to you by the Kansas Soybean Commission. The Soybean Checkoff, Progress Powered by Kansas Farmers.