Insect and disease attraction to plants with reducing sugars
How is it possible for a high Brix plant to be resistant to insects and not provide them with an abundant food source when insects are attracted to sugars? The key insight is that plants contain different concentrations of different carbohydrates at various levels of plant health. The goal for optimal plant health is to have all photosynthates and soluble sugars such as glucose and fructose converted to non-reducing sugars in each 24-hour photoperiod. This means a healthy plant will have a high Brix concentration and very low levels of reducing sugars.
From the podcast interview with Don Huber.
John: Are there any negative health consequences of plants having high levels of fructose and glucose?
Don: Yes and no, depending on what other stresses there are present. If you have a deficiency of manganese, for instance, it can’t store the reducing sugars―glucose and fructose―that are being produced through photosynthesis. It can’t store them as sucrose, and so they become very attractive reducing sugars, and they become very attractive to insect pests and to a number of plant pathogens.
Manganese is a critical factor for that sucrose-phosphate synthase enzyme that converts glucose and fructose into sucrose for storage. If you’re deficient in manganese, you’ll have high reducing sugars―glucose and fructose. As insects like aphids fly over these plants, they can detect that high reducing sugar, and for them, it’s a red flag saying, “Hey, come in for dinner!” But if those sugars are converted to sucrose and stored there, you don’t see that attraction.
Reducing sugars come out of the root system―they’re the root exudates that are attracting Pythium and Phytophthora and Aphanomyces and those other oomycete pathogens―root-rotting pathogens.
Later:
John: Don, you described how the carbohydrate profile can attract aphids. Are there other insects that can be attracted by the carbohydrate profile?
Don: A lot of them are. I don’t know that all of them are, but many recognize the difference between the reducing sugars, and they don’t seem to be attracted to the non-reducing sugars nearly as much. You’ll see that association. When we get the minerals balanced for the plant, you’ll see all of those problems start to disappear or be very minor.
P.S. I appeared as a guest on The Modern Acre podcast in this episode.
Soil quality for seed production
There is a story of a personal visit between Carey Reams and William Albrecht, both pioneers in soil mineral balancing and the human health implications. Carey Reams was in private consulting, based in Florida, while Albrecht was focused on Missouri and the Midwest.
Albrecht asked Reams, “What is the soil like in Florida?”
Reams responded, “Well, it would be a good place for some.”
The soil in this seed onion field reminded me of this story.
It is probably true that this location is an optimal environment for onion seed production from a climate perspective. It is also likely that onion seed production is a very profitable crop for the grower. It seems worth asking the question, is this use the highest good for the landscape?
Luther Burbank said, “Heredity is nothing more than stored environment.”
Would you prefer to buy seed grown in soil of this quality?
P.S. I am hosting an open Q&A Ask Me Anything style webinar on Friday at 12 noon EDT. You can sign up here. See you there.
Economic impact of cover crops and compost in orchard systems
From the podcast interview with Mike Omeg. A longer read, and very much worth the researched perspective.
John: Can you tell us about some of the things you tried that perhaps didn’t work so well, and then what you eventually ended up doing?
Mike: There are a lot of things I tried that didn’t work out well. We all like to talk about the successes, but oftentimes we can learn a great deal from failures. It was a mixed bag―like anything that is worthwhile, this was a complex project.
We started learning how we could enhance our soils and things we could do to boost our plants. One of the challenges that we had was how to scale that up―how to go from techniques that worked in, say, a small market garden―where the grower is selling directly to consumers and maybe only working part time―and scaling that up to the size of operation we have, which is 350 acres of fruit and 1,800 tons of fruit produced every year.
We started out with things that we thought would be simple and easy. One of those was putting compost on all acres that we have under management. We set a timeframe, because we couldn’t apply compost on all of those acres. What we found was that the logistical expense of moving thousands and thousands of yards of compost was huge. We had to go to the Portland metropolitan area, which is about 80 miles away, to get the volume of compost we needed. Getting that compost here, paying for the trucking, paying for an area where you can load that much material, buying or renting equipment that was out of our norm―bucket loaders and that sort of thing―became a real challenge for us. It was a really massive operation. It was a lot of diesel and a lot of steel, and that is not where I wanted to go with bio-intensive management of my farm.
I think that the compost did work for us. But if I were to do it again, I would have taken that capital that I invested in the compost and put it into other materials that we produce here on the farm or from other techniques. I think we could have probably had an equal or better return on our investment with a lot less giant equipment rolling up and down the roads and our orchard rows.
John: If you were to do it over again, where would you prioritize? Where would you focus, based on what you’ve observed?
Mike: I think that if I were to start at day zero again, in this process, I would focus a majority of my energy on mulches. What we learned over time was that the primary benefit we received from the compost was getting the soil underneath the tree covered with an organic material.
It didn’t matter as much what material was on top of the soil. We put pine chips on top of our soils. We put straw on top of our soils―wheat straw and grass-seed straw. What I found over time was that the compost was of course contributing nutrients. I love compost―but in my flower pots, not on an orchard scale.
The material we were applying wasn’t great compost. It wasn’t a super powerful compost with those humic components that we needed. It was really serving as a mulch. It protected the soil from the sun and from irrigation―the physical damage that irrigation causes.
In our orchard systems, we maintain a permanent side alleyway in between the tree rows. For generations, our family has been mowing that alleyway―like many other growers―and leaving the clippings sitting in the alleyway. What I arrived at was that if we could move that grass that we cut and windrow it right in the tree row, and cover the soil in the tree row, we could accomplish similar results to the compost with a fraction of the land, labor, and capital investment of the compost with practice we were already doing―mowing our alleyway rows.
If I were to pick one thing that we landed on that improved upon the compost, it would be to mow and blow. During the growing season we throw our grass clippings right onto the tree row. With cherries and other tree fruits, pruning is a very, very important process. We do it during the winter, during a dormant period of the orchard, and we generate a huge amount of carbon in the form of cut branches that we stack in the alleyway. And just like the grass, we used to mow that down and just leave it there.
But with mow-and-blow, we’re able to shred those prunings and move that carbon source over into the tree row. That’s a technique that really pushed us forward―getting the soil covered. I think that it allowed us to then put some very focused and very fine-tuned applications of nutrients and biological stimulants onto the soil―onto that mulch―and get a very rapid response, without the big earth-moving equipment that the compost required.
A valuable compost in our system is a very intentionally made, refined compost that can go on at a fraction of the amount that we applied when we used to buy thousands and thousands of yards of municipal compost. Instead, what we started doing was making a very small amount here on our farm―a nutrient-focused compost that incorporates nutrients we know we need. We put that material on in small amounts and get a lot more bang for our buck, because that compost is really a nutrient input instead of a mulch.
John: You’ve identified mow-and-blow as being foundational to building a soil cover within the tree row. What are the possibilities of using cover crops and producing even more biomass for that mow-and-blow operation, in addition to the grass that you’re growing?
Mike: We have begun to utilize cover crops in our alleyways. We maintain an alleyway between the trees that we can drive up and down. You need to have some kind of crop that’s growing there to hold the soil in place so that it doesn’t erode―to keep your orchard from turning into a dust bowl. We don’t want to have thousands of small dirt roads going up and down our alleyways, because that creates a giant dust plume that is bad for everybody, especially the soil and our trees.
We have maintained sod―a perennial ryegrass with creeping red fescue. There are orchardgrass sods. Many growers have their own favorites. That sod does its job―it holds the soil in place and keeps the dust down. But it does not contribute a whole lot to the trees. After we landed on the mow-and-blow technique, we started blowing what we already had in the alleyways over into the tree line. But I began to wonder if that was the best way to do it.
We eventually began to explore cover crops in order to generate more biomass in the alleyway and to transfer that biomass using our mowers over into the tree row to act as a mulch. We started cover cropping on fallow fields that were waiting to be planted. We would maintain cover crops there, and we had various mixes of plant species that we utilized. We just took the plants that worked in our fallow fields and started putting them in the alleyways.
We had some successes and some failures with that, because a big, open field with no trees growing above it is a very different environment for sun-loving cover crops than the shade of an orchard canopy in an alleyway. We have found a series of plants that we really like to put into our alleyways that generate a lot of biomass during the dormant season―basically from fall until spring. We don’t have a lot of equipment passing over our alleyways during that time, so the cover crops have an opportunity to grow.
Then in the spring, before we start our orchard management activities, when the alleyways are quite busy with equipment, we take that cover crop that grew over the winter and that generated a lot of biomass and we blow it into the tree row, and it generates a good start to our growing season for the cherries when the soil is starting to warm up. It gets this very nice coating of a diverse-species mix of mulch on top of it.
John: Mike, when you grow these cover crops during the winter months, doesn’t it have the effect of then choking out the sod? How do you manage that? Do you still have a sod for the following year?
Mike: We maintain two crops in our alleyways each year. We have an overwintering cover crop, and then we plant a fast-growing temporary sod. I don’t know if it would be proper to call the cover crop that grows during the warm season in our rows a true sod, but we maintain a green crop there. But it’s not grown as a cover crop because it’s very difficult to generate a whole lot of biomass when you have so many equipment passes going up and down the rows from May through August.
We were never able to find a warm season crop that we could plant and grow as a cover crop that would generate a lot of biomass. We just have too many different-sized pieces of equipment. By the time you take all those tire tracks and draw them out going down the alleyway, we really only end up with about 24 inches, right in the very center of the alley, where anything has an opportunity to grow. And keep in mind that it can’t grow that tall because the crown of the plant is constantly getting batted down by equipment passing over the top of it.
John: What you’re describing, if I’m understanding it correctly, is that you actually plant two crops―you plant what you’re considering a cover crop in the fall to produce biomass during the winter months, and then you’re planting a soil cover, or a ground cover, in the spring. Is that right?
Mike: Yes, that’s exactly what we do.
John: Can you tell us a little bit about the cover crops that you ended up selecting, particularly for winter cover? What was the rationale for those?
Mike: It was really difficult, because when I began my research, I quickly found that there was a giant laundry list of species that are available to us as growers. Keep in mind that our focus has been on what works―if it will sprout and grow and accomplish our goals.
It was very difficult to find anybody in orchards who was doing what we were. There was nobody I knew of that I could call and talk to and have an in-depth conversation about what species they were planting. There were people that were planting cover crops in fallow fields, but there wasn’t anyone who was planting them in the alleyway.
So, I took the species that grew the best in the fallow fields and tried them in the alleyways. I found that not every species did well; in fact, most species didn’t do well. But the species that we landed on, that did do a good job in the alleyways, really do a good job.
The mix we like in our alleyways is a mix of annual rye―all the row crop growers are maybe cringing when I say that, but it’s not a problem for us in our perennial system―with triticale, and then a mustard species, a hybrid forage kale, and a tillage radish. Those species work really well for us.
You might notice that I didn’t name a legume in that mix. That’s because we had difficulty finding a legume that would work in this application. We tried lots and lots of different ones, but we were never able to find one that worked for us. When we were evaluating legumes in our fallow fields and in our alleyways, voles and gophers would become a real issue for us. They were very attracted to the legumes. I avoided those because we didn’t find one that worked well, and the vole and gopher problem they generated was a big deal to us.
John: When you say that you didn’t find a legume that worked well for you, what were the parameters and characteristics you were looking for? Was it just because of slippery slopes? What were the constraints on the legumes, other than the gophers and the voles?
Mike: We evaluated a lot of different clover species. We found that they just didn’t establish well for us, consistently. When we talk about having a return on our investment, we need to have every seed that goes into that mix work―it needs to earn us a return. We just did not have consistent stands of clovers become established.
We did find that vetch could work for us. It would establish and it would grow, and it would be a benefit. But here’s the catch: it’s just not very well behaved at staying in the alleyway. It would take advantage of that nice open space underneath the tree, where it didn’t have competition from its companions in the alleyway. It would grow into the tree row, which would be fine until it would encounter a micro-sprinkler. We irrigate almost all of our acres by drip or micro-sprinkler irrigation. When that vetch vine would encounter the micro-sprinkler, it would whip up around it, and it would make the micro-sprinkler ineffective because it would cover the sprinkler. Because I couldn’t make vetch behave, I was forced to eliminate it from our mix.
John: Have you considered growing any cover crops in the tree row? Is that a possibility?
Mike: That’s something I would love to have happen for us. It seems so incredibly simple to say. Why can’t we just grow something in the tree row? Yet it is incredibly, incredibly complicated to find something that works.
I have tried countless species and countless mixes to grow underneath our trees in the tree row, and I am yet to find one that works really well. I’m sure people are wondering, “My gosh, what do you mean? Just look at all those species that you could plant.” But it is very difficult to find a plant that stays low enough to not interfere with our micro-sprinkler irrigation and that can grow well.
There are areas of the tree row that are in full, blazing sun all day, and yet that species also needs to be able to grow right up to the trunk of the tree, which may be in full shade for almost the entire duration of the day. Most importantly, it has to compete with weeds that grow in a tree row―weeds that we unfortunately can’t allow to be there because of the micro-sprinkler irrigation.
John: And it has to survive being buried underneath the mow-and-blow mulch and still emerge and remain short while doing all those things.
Mike: Yes, and handle foot traffic. There’s not a lot of foot traffic in the tree row except during harvest. Then, several hundred people enter a small block, and those people have to trample around the tree to get the fruit picked. That tramples a lot of cover crops.
I have not yet found the plant that accomplishes everything. There are things that grow beautifully underneath young trees―trees that don’t have a big canopy and aren’t in production. But as soon as those trees get up and start to shade―as soon as we start having pruning activity―we would trample those cover crops down. The mow-and-blow brings a whole new dynamic because there’s nothing I have found that will not interfere with the micro sprinklers and that can take that mulch getting put on top
I’m open to any ideas. There are a couple of species that do okay. But to plant hundreds of acres of them is impossible. They may be a tuber, or they may be a bulb, or we may need to start them as a small potted plant. That’s practical under a few trees or in a backyard scenario, or maybe a smaller orchard. But when you talk about hundreds or thousands of acres, you could be talking about millions of plants, and you can’t find a horticultural nursery that could produce them for you economically. It’s a real challenge.
I found some species that I thought were great. But after we got a foot of snow on the ground, the gophers also thought they were great, and they were gone come spring.
John: It’s an interesting set of challenging conditions. Can you tell us a little bit about some of the species that you experimented with that were tubers or potted plants?
Mike: I can. Three of them did a good job, but we just weren’t able to scale them effectively. One of them was ajuga―Ajuga reptans. We planted not the variegated types or anything―the fancy ones―just the wild type. The second plant is moneywort―Lysimachia nummularia. It worked quite well. Again, it was just something that was impossible for us to scale. And then the third species is a non-hybrid comfrey―Symphytum officinale var. patens―that we found worked very nicely.
Understanding the source causes
Only knowing what to do, without understanding or questioning why we do it, is not particularly useful knowledge in the long term.
Knowledge of what but not why generally leads to destructive results at some point.
To have truly regenerative agriculture requires that we have cumulative constructive outcomes from our management decisions, not destructive ones.
To consistently achieve constructive outcomes, such as the continual renewal of soil health, plant health, livestock health, ecosystem health, and human health we need to understand WHY things work a certain way in our soil/plant ecosystems.
In July this year, I taught a two-day intensive course where we focused on describing why.
Why do we have diseases only on some varieties? Why do insects only show up in certain parts of a field first? Why does weed pressure become more intense with continued herbicide applications? Why do some weeds show up in certain fields and not in others? Why do some crops require more fungicide applications than they did a decade ago? Why do some crops not produce the marketable yield they seem to promise earlier in the year?
Understanding why is very empowering, because it gives us the knowledge we need to change the conditions to produce different outcomes. Positive outcomes that benefit the health of everything we manage, particularly our bottom line.
We just released the recording of this two-day course this morning at the Regen Ag Academy.
Fungal mycelium and shutting down phytophthora in peppers
A bell pepper field had phytophthora problems severe enough to cost the entire crop.
Ridomil Gold treatments were known to be completely ineffective.
Instead of anti-biotics, we applied pro-biotics, microbial inoculants of mycorrhizal fungi, a range of bacterial species, and biostimulants through the drip irrigation system.
Within weeks the soil is filled with these thick strands of mycelium/plant roots and the crop recovered completely.
The phytophthora symptoms disappeared.
What have you seen something similar to this in the soil? What do you think this might be?
Rapidly regenerating tired greenhouse soil
Several years ago we worked with a greenhouse grower where crops were being grown in the soil continuously for over a decade. The soil was quite sandy and became quite tired as you can imagine. The large investment in the greenhouse made it worthwhile to invest in regenerating soil health.
The grower green chopped cover crops grown in the field, applied them to the soil surface to a depth of several inches, sprayed Rejuvenate and Spectrum on the residue, and incorporated it into the soil. In 3 weeks the soil had noticeably darkened in color and had developed good aggregation.
The following crops grew better than they ever had in recent memory, and without any disease or insect pressure. Biology can regenerate soil health quickly and provide all the nutrition a crop requires when given a food source.
The soil sample on the right is from an untreated greenhouse bay, taken at the same time.
How to create a disease susceptible orchard
Leaf residue can carry potential disease pathogens from one season to the next.
The best short term solution to solve it is to apply Soil Primer to have the residue be rapidly digested and broken down.
The midterm solution is to cover the naked soil and provide the existing biology a food source so they can thrive and accomplish the job on their own. Stop the continuous herbicide applications.
This picture was taken in the dormant season, but I don’t need to see these trees during the growing season to know they are immune-compromised, susceptible to insects, susceptible to diseases, and biennial bearing. I can know this to be the case because it obvious this soil is not capable of delivering the nutrition the crop needs to be healthy and high yielding.
Tight node spacing on cotton for high yields
Cotton is commonly grown with high rates of nitrogen and multiple aggressive PGR applications to keep internodes tight and increase yields. If you think that is a bit like driving by holding both the accelerator and the brake to the floor, you would be correct.
In this podcast episode on vegetative vs reproductive nutrients, I describe how to manage nutrition to produce rapid vegetative growth and tightly spaced nodes at the same time, producing high yields and high-quality fiber at the same time.
The nutrition on this field has been managed differently than the mainstream. Instead of having excessive vegetative growth, this field has almost too little, partially because of cover crop residue tying up nitrogen. No PGRs have been applied, node spacing is tight, and the crop is on track for an exceptional yield.
And isn’t the photo just beautiful? Life in agriculture is just awesome, isn’t it?
P.S. I am hosting a Book Discussion on the questions and ideas you raised from Quality Agriculture, tomorrow, August 28th, at 12:00 EDT. You can register here and bring your questions! See you then.
Why do we have water stressed crops with 30 inches of rain?
Providing enough water to our crops is the one thing we stress about more often than almost anything else.
We joke that we worry about drought when there is nothing we can actually do about it. Actually, we can, if we want to.
There is a lot we can do about providing a crop with a season-long water supply in the soil reservoir.
We forget that water infiltration and percolation are two very different things. There is no correlation between the quantity of water that falls on an acre of soil, the amount of that water that is held in the soil, and the amount of the held water that is actually available for plants to absorb. Some soils can deliver almost 100% of the annual rainfall to the crop as available water during the growing season, and other soils may deliver less than 40%. This explains why we have drought-stressed crops in regions that receive 30 inches of annual rainfall.
In a new course titled Why do we have water stressed crops with 30 inches of rain? that is being released from the Regen Ag Academy today, Jerry Hatfield describes soil and atmospheric water dynamics we should keep in mind to help us manage water better and ensure our crops get the benefit of the rainfall the land receives. You don’t want to miss it.
