Focusing on biology has helped me steward Lakeside Farm in northern Michigan for 45 years
With a comfortable breeze, blue sky and sunshine, it was the perfect kind of day for the crowd that had gathered for our Lakeside Farm Soil Health Field Day last July. The nearly chest-high buckwheat was in full bloom, with a crew of bees in full-on harvest mode, as presenter Gary Zimmer stood among them extolling the many virtues of cover crops, soil biology, and all of the magic that happens both above and below the soil surface in an active ecosystem.
Having heard Gary speak many times, it was somewhat surreal to not only be a part of this knowledge sharing but to also to hear his generous compliments of our farm throughout the day. Perhaps most resonating to me was the statement, “Do you realize that 75 cuttings of hay have come off these fields, and it was all run down and poor fertility when he started? You can’t do that by just throwing seeds on the ground.”
It was at this point that I happened to realize where we were all standing and the significance of this location. This happened to be the same field where I had first started to regenerate abandoned farmland 45 years earlier, with a one-bottom plow, some antique horsedrawn equipment, and equally primitive knowledge of soils. My journey to regenerate these degraded soils had begun right there. A small portion of the field is still producing a good crop of hay every year, having been tilled, cover cropped and reseeded only once since that initial seeding in 1980.
Selling hay off the farm is typically regarded as a nutrient- and minerally extractive use of land. But every farm has its mortgage lifter, and for me this has always been the square bale of mainly horse hay. Even having harvested more than 75 cuttings, though, the soil tests show slow but sustainable improvement. The extractive nature of removing hay has been offset by a multitude of positives — mostly having a perennial, photosynthesizing, living-roots crop with an undisturbed active soil microbiome, allowing the proper functioning of this system. It is the same concept that we relate to the farm’s valuable maple veneer woodlots: “harvest the interest and grow the principal.”
In 1980, the vegetation within this particular area of the field consisted only of a dense covering of green moss across its sandy surface. The transformation exemplifies the potential of even naturally very poor soil — given enough time and attempts at proper management, we can not only regenerate soil but can go further and actually generate soil.
No, this is not the suggestion of yet another buzzword. The concept of “generative agriculture” is very real for glacial areas such as this, with its minimal topsoil. When I pull soil tests from never-disturbed woodlands directly adjacent to my regenerated croplands, I can see how close the soil organic matter numbers actually are. Given enough time and proper management, it is very possible to exceed the natural condition of the native soil, thus generating more productive and resilient soil. Unfortunately, we may also be at a point in time where we need to generate more resilient soils that will function under evermore challenging climatic conditions that did not exist just a decade or so ago.
Building Carbon with Rye — and Corn
But our farm isn’t only hay and the aforementioned maple woodlots. We also rotate grains, including corn, into our soil-building rotations. And a vital component of our corn system is one of Gary Zimmer’s favorite crops: cereal rye.
The term “cover crop” doesn’t do justice to the multi-faceted practice of planting some type or combination of species of plants prior to or following the primary crop. A yearly example of this on our farm — one that’s common to many farms — is the practice of planting cereal rye following corn harvest.
Given our northern location — above the forty-fifth parallel — and lacking the ability to mechanically dry harvested corn, I often plant rye into snow-covered fields. This task is certainly made easier with a heated cab and four-wheel drive! It goes very quickly, though, with a bulk spreader, followed by chopping the stalks with a bat-wing rotary mower. This provides a beautiful blanket of shredded mulch over the seed.
In years with a late winter, the rye may actually grow an inch or two tall prior to snowfall. The cold weather can accelerate the oxidation of the outer seed layer, leading to faster germination. Either way, the rye will typically be two to three feet tall when I terminate it immediately prior to planting. At this point, the plant is preparing to start its reproductive stage and has slowed or ceased the exudation of sugars to the roots. These exudates are what builds the majority of the stabile carbon, humus or organic matter.
At this more mature plant stage, the higher lignin and (depending on the species) cellulosic levels of plant stems will also break down slower, providing a longer microbial and fungal food supply. It can also provide storage of moisture and nutrients that are then available to the soil’s mycorrhizal network. This can be observed visually by carefully exposing fine mycorrhizae-like filaments and noticing how they are attached to each end of a piece of slower-decaying crop residue like a cornstalk.
This material can also be a source of enzymes that are necessary for the microbes decomposing the material and bonding amino acids together into complete proteins, which are essential for plant health. This takes the healthy plants off the menu for ravaging insects to devour. This decaying organic material may not be as critical in higher-producing soils, but it is essential to at least temporarily increase surface areas in sandy and highly degraded soil conditions.
While this late establishment practice may not have the ability to sequester all of the available nitrogen from the prior year, it still offers enough benefits to more than offset the very minimal cost. I plant the rye at a rate of one and a half to two bushels per acre.
Far too often we hear the excuse that we’re too far north to establish cover crops. I have not found this to be the case most years. Rye can photosynthesize down to 38°F, so even in the spring there is typically a sufficient window for ample growth prior to termination. It takes just a few warm days before the previous year’s shredded stalks and other residue is no longer visible amid the rapidly growing rye crop. The green rye is now first in line to absorb the CO2 given off by the decaying mulch mat from the previous year’s forage crop. You either use it or lose it into the atmosphere.
While I love multi-species blends and the synergistic positive results they offer, I have achieved my best results in regenerating degraded light, sandy soils via a rotation of late-summer-seeded rye followed by three years of grain corn, with post-harvest seeded rye each year. If the final year of corn harvest is late, I will forgo the rye, as there is not enough time for sufficient growth in the spring prior to an early planting of oats and peas. These are baled and wrapped in late June, allowing time for a summer cover crop before an early-September seeding of a hay crop of alfalfa and multiple grass species.
This new seeding seems to benefit greatly from the newly incorporated, lush-green, short-term cover crop. It provides a total of eight photosynthesizing, residue-generating crops, with a combination of mature, brown-carbon corn residue; somewhat-mature green rye; and at least one crop of a succulent lush-green material.
While some may disagree on the soil-building benefits of corn, I have found it to be an essential part of regenerating marginal soil. With the size of the stalk and the massive and plentiful leaf structure, combined with an extensive root system, corn is a root-exudating and carbonaceous-material-producing machine. On any field that yields even a breakeven crop, I may not recognize the profits for a few years — until harvesting many cuttings of hay in the future — but they will come.
This is typical of soil-building practices such as cover crops and mineral deficiency corrections — they are not always quantifiable in yield immediately that year, but their ROI can be recognized for many years going forward. We have become so accustomed to instant gratification that it can be easy to forget the long-term nature of what we are actually working with: the earth itself.
Interseeding Rye into Knee-high Corn
In addition to planting rye after corn harvest, I have also had decent success inter-seeding cereal rye about five to six weeks after planting the corn, using a three-point mounted broadcast seeder. For the limited acres of corn that I grow, this is a quick and easy method to plant a rye cover crop. The corn canopy directs the majority the seed toward the center portion of the rows. With little moisture and sunlight, the aboveground germinated rye struggles until early fall, when additional moisture and sunlight become available as the corn leaves dry down, allowing the rye to really takeoff and form a beautiful, lush mat of dark-green rye.
When you observe the small, spindly rye during the middle of the summer, you realize there is no way that there is any yield drag on the corn. The rye tends to grow closer to the ground this time of year, which is ideal for post-harvest stalk chopping. By mid-spring, the stalk residue is barely visible, and the well-established rye takes full advantage of the sun and rains. It grows rapidly both above and (more importantly) below the ground — rye plants are reportedly able to produce upwards of 6,000 miles of roots through a continual pulsing and sloughing of roots.
This method provides a green plant 365 days of the year. The shallowly incorporated rye stays green, and its roots still alive until the corn pokes through the surface, ensuring a steady diet for the microbial community.
This system also works well for small grains following corn, which are seeded earlier in the spring, requiring the adolescent rye to be incorporated at a readily digestible stage. This helps get the young oats or barley off to a great start. With a straw chopper on the combine, the straw residue makes for a good thatch cover, followed by a light discing to help germinate the fines coming out of the back of the combine. With the cooler weather and typically increased moisture of late summer, this no-cost volunteer cover crop achieves a good four to six inches of growth prior to shallow incorporating and culti-mulching, just prior to fall seeding of alfalfa and multiple grass species blends.
This is often not the easiest crop to establish on light soils and greatly benefits from the boost of the newly decaying green matter. For fields that were not scheduled to be reseeded, the volunteer crop is left to grow, with rye interseeded into it simply by bulk spreading once there is adequate moisture in the fall. The volunteer crop eventually winterkills, leaving a thriving rye crop in the spring. Including the harvested grain crop, this totals four green crops growing throughout the year. Again, this is in northern Michigan — so I’ve really never understood the excuse of being too far north to grow cover crops.
Finally, whether with rye or any of the other vast array of cover crops available today, it is a crop. On marginal soils, therefore, it is going to preform much better with additional fertility. On better soils, the crop may be fine if there are adequate nutrients for the rye to scavenge, but on nutrient-deficient soils I have found it far more beneficial to provide some form of nutrients, allowing the plant to develop to its full potential.
Having a Field Day with Biology
We are blessed to have the opportunity to steward this land. Land stewardship is a gift held by only a small segment of the overall population, and therefore much is required of us — especially given the many potentially positive and negative impacts agriculture can have on the rest of society. Our farm is no exception here, with its aptly named location on and within the watersheds of our pristine northern lakes, necessitating extra vigilance in regard to leaching and surface runoff. Our location also provides not only a beautiful scenic backdrop but a very visual example of the importance of agriculture and its ability to responsibly and ecologically co-exist within more natural surroundings.
By recognizing and managing the many benefits of a biological farming system, we not only have the ability to operate in an ecologically sustainable manner, but to also increase profitability through reduced yearly input costs. In addition, there exists the longer term, yet-to-be-realized financial gains as the soil function and output increase each season, building a form of soil equity.
Biological farming methods allow us to harness the intricate natural capabilities of the soil by leveraging minimal and thoughtful inputs, providing increased outputs through a system operating in balance, providing for a better quality of life for us all.
Dave Skornia has farmed for 45 years at Lakeside Farm in northern Michigan.
