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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.

2020-08-25T14:29:57-05:00August 27th, 2020|Tags: , |

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.

2020-08-26T11:45:47-05:00August 26th, 2020|Tags: , |

Plant flexibility and unhealthy brace roots

Copper is known to provide flexibility to plant structures. Stems become flexible, plants can bend in high winds, and stand back up afterward, without any breaking or lodging. Twigs and branches become more flexible and don’t break as easily. Spurs and fruit clusters become less fragile and breakable. Crops that are sometimes known for ‘brittle’ leaves like broccoli don’t have the leaves snap off as easily. Fruit skin becomes more flexible and very slightly stretchable, allowing for fruit expansion right at maturity with additional moisture without cracking and splitting.  Copper provides all of these benefits because it enhances the formation of lignins in the structural tissue. We have observed all of these benefits occurring in the field.

When grain crops have adequate copper, they develop very flexible stems. A corn plant should be able to bend when gripping the stalk immediately above the ear until the tassel brushes the ground, with no strain, and stand right back up again. This gives grain crops a lot of resilience to severe weather stress and physical abuse.

This also means plants do not need so-called ‘brace roots’. At least not to ‘brace’ themselves. ‘Brace’ roots only show when the plant’s vascular tissue is plugged immediately below the node. As soon as the vascular tissue begins plugging, plants quickly send out emergency bypass roots at the node, above the plugged transport pipeline. When the pipeline plugs again one node higher, the plants send out another set of brace roots. The worse the plugging is over the season, the more sets of brace roots a corn plant will extend.

Vascular tissue (xylem) plugging seems to occur when plants are absorbing a great deal of oxidized iron, sometimes aluminum, and seems to be associated with herbicide use. The more herbicides that have been used historically, the worse plugging and brace root expression seems to become.

This means brace roots are in reality a negative signal of plant health.

In cases of extreme vascular plugging, there is so much growth from the node, individual roots are not even visible, but the growth is in a continuous band. In cases where the soil has a toxic accumulation of herbicide, the brace roots may grow down toward the soil surface, and then curve back and point upward again, as they seek to avoid the toxic soil.

It is possible to grow corn crops with no brace roots. A grower sent me this photo of a buffer strip between an organic field and herbicide sprayed field. The buffer is cultivated for weed control. I didn’t personally visit, so my best guess is the cultivated side on the right has had one set of brace roots buried from soil movement. In any case both of these crops have either only a single set, or no brace roots.

Have you observed corn with a continuous band of brace root growth, or where the brace roots turn up and away from the soil? I would love to see your photos and share them.

P.S. We have a big announcement coming tomorrow. Stay tuned!

2020-08-24T19:02:13-05:00August 25th, 2020|Tags: , , |

Oak trees add a lot more than water to a hillside

In this post last week I asked for your thoughts what might be contributing this green island effect underneath the trees in this photo I took while driving through California a few years ago.

I received a lot of responses. Thank you to all who shared your thoughts!

The most common response referenced the capacity of oak trees as dynamic accumulators and the contribution of leaf litter to the soil with its associated nutrient content and biological stimulation.

Other proposed possible answers included:

  • Shade from sunlight and heat
  • Moisture drip from the canopy, fog/dew accumulation
  • Slowing rainfall and increasing infiltration
  • Livestock concentrating under the shade
  • Mycorrhizal fungi
  • Protection from freezing
  • Nitrogen contribution of higher organic matter/leaf residue
  • Fertility contribution from nuts/mast crop
  • Root system pattern
  • Tree root exudates
  • Deep tree roots pulling up water
  • Different grass species, growing at different times
  • Most probably some combination of the above

My guess is that some of these factors are unlikely to be significant contributors in this local context, though they may be in other environments. Shade seems unlikely because the direction from the tree canopy is not uniform. There is no livestock grazing in this landscape (sadly), and freezing protection seems improbable given that it is central California.

The good news is, we don’t need to speculate what all might be going on. Thank you to Jeff Herrick and Leslie Roche for sharing references that point us in the right direction.

The abstract from the paper Blue oak enhance soil quality in California oak woodlands1 is succinct and to the point:

Blue oaks create islands of enhanced soil quality and fertility beneath their canopy. The quality of soil beneath the oak canopy is considerably better than that of the grasslands adjacent to the trees. We found evidence of improved soil quality under blue oaks for physical, chemical and biological soil properties. The type of vegetation (oak versus annual grasses) has a much stronger influence on soil organic matter and nutrient pools than does soil parent material. Removal of oak trees results in a rapid deterioration of soil quality with the majority of the loss occurring within 10 to 20 years after tree removal.

The article is interesting reading in its description of how oak trees contribute to soil fertility.

This observation and discussion raises lots of interesting questions, but the most obvious one is, “What are we missing by not including oak and other tree species in our agricultural landscapes?”

 

  1. Dahlgren, R., Horwath, W., Tate, K. W., Camping, T. & Others. Blue oak enhance soil quality in California oak woodlands. Calif. Agric. 57, 42–47 (2003).
  2. Eastburn, D. J., O’Geen, A. T., Tate, K. W. & Roche, L. M. Multiple ecosystem services in a working landscape. PLoS One 12, e0166595 (2017).

 

2020-08-21T09:13:03-05:00August 24th, 2020|Tags: , |

Root systems and stem diameter needed to achieve yield potential

There are a number of crops where the plants express a large untapped genetic yield potential.

Well managed cantaloupe plants will regularly pollinate, set, and begin sizing over 20 melons per plant until they are about 2 inches in diameter. Then most of them will abort. Exceptional yields are 10,000 melons per acre from 4000 plants or 2.5 melons per plant.

Grape tomatoes can have as many as 150 blossoms per cluster, yet only produce 35-50 marketable fruit per cluster. Tree fruit and nuts can set many more fruit than they can fill to marketable size. We expect ‘June drop’ as a common phenomenon where trees abort many of the set fruit embryos. (How much calcium and trace minerals are exported from the tree when these fruitlets drop after the cell division stage?)

We know the significant factor that limits the realization of yield potential for many crops is environmental/nutritional stress.

There is another significant factor that is less well understood, partially because many of us have not observed 50+ years of plant breeding work, and the gradual evolution of changing plant expression.

Most modern varieties of the crops I have mentioned, and other crops, have the genetic predisposition to develop many blossoms and set a lot of fruit. And they lack the root system and stem diameter to supply water and nutrients to fill all these fruits.

Many modern cucurbit varieties have comparatively weak root systems when compared with older varieties, and they have thinner diameter vines. The reason some watermelon are grafted on gourd rootstock, and some tomatoes are grafted on cherry tomato rootstock is that the rootstock has a much more robust root system, and delivers more nutrition to the crop through a larger diameter stem.

Ed Curry, the chili pepper breeder I interviewed on the podcast has been able to increase the average yield of chili peppers by more than two times over 40 years of breeding work, largely by focusing on developing varieties with a large stem size, and a robust root system. A narrow diameter stem can not deliver the water and nutrients needed to realize the yields many plants are genetically capable of.

What have you observed about root system size and stem diameter over the years?

2020-08-20T21:16:39-05:00August 21st, 2020|Tags: , |

Trees add water to the hillside

A California hillside during the dormant season.

What are the trees adding to the landscape to produce the circle of green grass? Mycorrhizal colonization? Shade?

When you look at the outlines closely, the patterns all move to the downhill side. There does not seem to be a correlation to sunlight direction.

I suspect the trees are capturing water from the atmosphere and transferring it to the soil. Increased soil moisture is the only thing I can think of that would move downslope consistently.

What do you think is happening here?

2020-08-17T15:07:45-05:00August 18th, 2020|Tags: |

Powdery mildew resistance on butternut squash

It would be common for organic butternut squash in Pennsylvania to be shutting down from powdery mildew pressure by mid-September. While neighboring growers had crops that collapsed completely, we could find no powdery mildew in this crop at all. The grower credited foliar applications of SeaShield, Micro 5000, HoloCal, MicroPak, and SeaStim for the plant health and vigor we observed in this 2017 crop.

2020-08-13T05:51:04-05:00August 13th, 2020|Tags: , |

Green bean seedling vigor

When our goal is to have seed germinate quickly, establish large root systems, and have strong seedling vigor, we need to support seeds with the trace minerals and biological symbionts they should have had if they were grown in optimal conditions.

The row starter solutions we recommend always include microbial inoculants and a broad range of trace minerals.

This field of organic green beans was planted with an AEA row starter applied in-furrow.  The two check blocks are comparisons of competing products. I don’t know what they contained, but it seems safe to suggest they lacked the nutritional and microbial support needed to establish strong seedling vigor and build the plant frame needed for large yields.

2020-08-04T16:59:10-05:00August 10th, 2020|Tags: , |

Speeding up maturity with nutrition management

For some vegetable crops, we have gotten into the habit of planting only transplants, because seed quality and soil health has eroded to the point where poor seedling vigor has become ‘normal’, and transplants perform better.

When we manage soil health and use good seed treatments and microbial inoculants, seed germination and seedling vigor can be dramatically improved, and we can get to harvest much faster.

It is common for acorn squash to have their first full-size fruit 8-12 weeks after being direct-seeded, and many growers in the east have begun using transplants to speed up crop maturity before mildew pressure becomes too severe.

These organic acorn squash have developed the first full-size fruit 5 weeks after being direct-seeded, at least 3 weeks earlier than normal. This hastened crop development and earlier maturing fruit is a common expression of healthy plants with optimal nutrition. It is possible to speed up the maturity of many crops from 5% – 20% by managing nutrition and biology.

How much of a difference would it make for your crop if you were able to harvest a week or two earlier?

P.S. I am hosting a Zoom video AskMeAnything discussion today at 1 PM EDT. You don’t need to register in advance, just connect here at 1 PM.  See you there!

2020-08-04T16:40:28-05:00August 7th, 2020|Tags: |

Field results of nutrition management on freeze resistance, bacterial canker and powdery mildew in cherries

From the podcast interview with Mike Omeg:

John: Mike, you’ve been talking about the returns in very abstract terminology of return on investment, etc. Tell us about results. What has changed with your trees? We started this conversation by mentioning a desire to develop the root systems. What has changed with your root systems? What has changed with tree health? What have you actually observed in the field?

Mike: I have some anecdotes and then I have some actual data to share. Let’s start with the anecdotes.

In November of 2014, we had one of those once-in-a-lifetime historic freezes. The lowest the temperature had been was 43 degrees. Our trees generally go into dormancy in November, but it had been a very warm fall and the trees were still actively growing. We hadn’t had any acclimation to the cold. Then we had an arctic front come down, and we went from lows in the 40s to below zero in one day, and it stayed below zero. Here at my house, we had -4 degrees Fahrenheit.

The leaves on the trees just turned black. Just like a dahlia plant looks after the first frost, the leaves turned black, and they just hung on the trees. Several hundred acres of trees in our area just died. We had blocks where all the buds were frozen on the trees.

At that time, I was doing some comparison and analysis between mulch and intensive bionutrient applications and conventional applications for management of the orchard. I had two orchards that were sitting within a quarter-mile of each other at the same elevation. One was on one side of a small canyon and one was on the other. They were the same age and variety of trees and had the same irrigation. The only difference between them was the nutrition management. One had received compost mulch and bio-intensive nutrition, and the other orchard was just a standard conventional orchard.

After that freeze, all the trees in the conventional orchard were dead. They froze and the entire canopy was killed. We could have regrown them from the roots, but the trees were dead down to the soil. The entire orchard was smoked. There wasn’t one tree left. When you went and cut bark, it was black underneath instead of bright green. I had to remove that orchard the following spring

The orchard where we’d been following these bio-intensive practices, believe it or not, had 110 percent of a normal crop that year. We actually picked 10 percent more fruit out of that orchard than we did the previous year. That truly amazed me. That difference was only due to the nutrition management and these other activities that we were doing. There was no other difference.

The other thing that we’ve observed over time is a marked reduction in two pathogens that are problems for us with cherries. One of them is bacterial canker. Bacterial canker causes cherry trees to eventually die. They create a lot of gum. The trees get a canker that has a swelling of sap under the bark, and then these cankers burst, almost like a blister, and sap oozes out of them. That disease is a particular challenge with certain varieties and certain rootstocks of trees. If it doesn’t wipe the orchard out, it takes enough trees out that you lose the value of that block as an economic unit.

The consultants at Advancing Eco Agriculture I work with started to tell me that we should try to take on bacterial canker by focusing on nutrition. Over time we had an amazing transformation in a block that had significant amounts of bacterial canker—enough that I was going to take the block out. But I left it there because I didn’t have anything to lose.

Bacterial canker was actually eliminated from that block. It wasn’t just reduced—it was actually eliminated. Virtually all of the trees in that block had one or more canker sites on them. Some were far worse than others, but almost every tree had at least one canker on it. By the third or fourth year, we could not find bacterial canker in that block. I had neighbors coming to the block. I had extension staff and research pathologists from Oregon State coming to that block, and they could not believe the change.

The second disease that is more problematic in cherries is powdery mildew. That disease affects the foliage and fruit. It’s a real challenge. Powdery mildew is the disease that is targeted by almost all the fungicide applications that are applied in conventional and organic production of cherries. What we’ve seen is that highly susceptible varieties normally would require extra powdery mildew applications. But we’ve been able to reduce our applications by half, and maybe I could reduce them by more—I’m just a bit nervous about reducing them by more. But we have been able to apply half the number of fungicides to those trees, and we have no mildew there.

This is another thing that neighbors couldn’t believe, so we actually had a walking tour through that block. One of them was hosted by extension. I made a bet with the neighbors—I said, “Find any mildew in this block and I’ll buy you a steak dinner.” I’ve never had to buy a steak dinner because folks can’t find mildew in that orchard. A typical orchard with that variety in it would have lots of mildew because even with fungicide applications we are not able to control it.

Those are two things that that we’ve observed that I honestly thought would never happen. Through nutrition, we’re able to manage our diseases—in this case, with bacterial canker, and with powdery mildew. It speaks to the long-term value to the orchard of providing the nutrition that the tree needs. Do that and the tree will take care of itself.

–

P.S. I am hosting a Zoom video AskMeAnything discussion on Friday at 1 PM EDT. You don’t need to register in advance, just connect here at 1 PM.  See you there!

2020-08-04T16:39:53-05:00August 6th, 2020|Tags: , , , , , , |
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