Cover Crops: How to Grow a Shag Carpet

Yes, I pretty much just dated myself as a child born in the late 60's, grew up in the 70's with that title. If you're old enough to enough to remember raking the carpet as something on your chore list, then we might be of the same age, especially if you remember having a chore list that didn't end with an allowance!

So if you've followed my blog for any length of time, you know that we've been doing cover crops for more than 40 years. You'll remember this picture from the 1960's of my father in law getting ready to seed No Till cover crops into the corn field to the right of this Hi-Boy cover crop seeder. Cover crops are part of our family farming operation because they are what helps us grow a shag carpet.

If you remember walking on a shag carpet, especially after it has been recently raked, you know that the carpet has deep pile, something you could sink your toes into. That's the goal of our soil management program on our farm... to have soil that feels like a shag carpet when you walk on it. In agronomic terms, we call this "tilth". Tilth is the physical condition of the soil that allows for a healthy root system to support plant growth and plant health. Having soil with good tilth or that feels like a shag carpet means that the soil has large pore spaces for oxygenation and water filtration.

While Maryland farmers use a lot of cover crops in an effort to help reduce nutrients from leaving the soil for the protection of the Chesapeake Bay, that is really a secondary reason for us to use cover crops. We use cover crops primarily to improve our soil health, and specifically our soil tilth.

Here are some of the cover crops we plant and why:

Crimson Clover: We use a lot of this as a slow release nitrogen source for perennial crops like our grapes. Besides being a legume which adds nitrogen to the soil, also provides a lot of biomass when it is incorporated into the soil. This organic matter helps add structure to the soil which helps stabilize the soil from erosion, improves water holding capacity of the soil, and its decomposition adds microbial activity to the soil. Besides that they're a good habitat when in bloom in the spring for attracting beneficial insects.

Tillage Radish: I took this picture while combining corn last week. The radish seed was aerial seeded rather than drilled or planted (we no longer have that old fashioned Hi-Boy seeder from the 1960's.) Aerial seeding allows us to spread the cover crop early enough in the late summer or fall to allow for good germination. In order to get a good stand of any crop, you need good seed to soil contact, adequate sunlight and warm temperatures for germination. Today it is 26 degrees at Noon. It is too cold for seeds to germinate at this point. Tillage radish grows a long tap root which creates nice pores in the soil which help break up compaction from driving across fields with equipment, as well as acts as a "sink" for nutrients that the previous crop did not use this season. The radish stores those nutrients in its root. When it winter kills and the ground thaws out, the radish will decompose and release those nutrients back into the soil for the next crop to take up.

The aerial seeded tillage radish seen above is mixed with annual rye. It was seeded before we harvested the corn, then once the cover crop is no longer fully shaded by corn, it greens up and gets to work on the soil tilth. Along with decomposition of the corn stalks into the soil, over time, we work to increase the organic matter and create a soft, well structured soil that feels like a shag carpet when you walk across it.

This field above has a mixed species cover crop of tillage radish, crimson clover, and barley. It was drilled rather than aerial seeded. When we do a mixed species cover crop, it is to address several issues. Barley is good a taking up excess moisture and suppressing weeds which combined with the nutrient scavenging of crimson clover and the compaction reduction of tillage radish, is one of our preferred cover crop mixes.

So cover crops is only part of the shag carpet equation. The package deal is that soil management is a practice of adding organic matter, reducing compaction, improving the nutrient profile, and working at improving the structure of the soil so that the next season of crops is grown in healthy soils and so that the next generation of our family has healthy soils to continue of family farming legacy. To maintain a profitable family farm, you need to be constantly improving your soils. Decades of cover crop management has shown us the benefits to doing so.

Healthy Soils, Healthy Foods!

I was asked to write an article for the Academy of Nutrition and Dietetic's Food and Nutrition Magazine on soil health and its relationship to food. For me as a dietitian turned farmer, its interesting how much cross over there is between human nutrition and soil and plant nutrition. Looking a soil and plant tissue analyses is very much like reviewing  a patient's bloodwork. Its a snapshot of health and nutritional status. So while I am no longer prescribing diets for people, I do practice nutrition by prescribing diets for the crops we grow.

Click the link below to go to the online article:

Healthy Soils, Healthy Foods

There are also 2 really good videos from USDA's Natural Resource Conservation Service that I've linked below.  One covers all the basics about soil and its health. The other is a good video on farmers adopting cover crops. They are both about 30 minutes long but worth the watching if you want to learn more!

Soil Stories - The Whole Story

Under Cover Farmers

Food Fight: Organic or Conventional?

This week a study from Stanford University created quite a buzz about our food and our food supply system. The study published in the Annals of Internal Medicine was entitled: "Are Organic Foods Safer or Healthier Than Conventional Alternatives?: A Systematic Review." (Smith-Spangler et al, Ann Intern Med. 2012;157(5):348-366). The authors looked at 45 years worth of published research comparing the nutritional differences between the two farming systems. The crib notes version of what they found was that there was no significant difference in nutritional value between organically produced foods and conventionally produced foods.

Likewise, the American Journal of Clinical Nutrition published a similar study in 2010 looking at over 50 years of research and reached a similar conclusion. (Dangour et al, Am J Clin Nutr. 2010: 92:203-10.)

My purely anecdotal conclusion from my own farming operation would concur with the results of these reviews. The nutritional value of what you eat is a direct result of the quality of the soil it is grown in. The soil quality is not dependent on a "farming system" ie: organic or conventional. Soil quality is contingent on the care and stewardship of the farmer farming the land. Care and stewardship are not "farming systems" but philosophies that work within both farming systems. Care and stewardship are not mutually exclusive to conventional farming. Visit a family farm and you will discover quite the opposite is true.

Soil condition and quality is a direct result of care and stewardship and will reflect the nutrients of that care and stewardship, as well as the nutrients that are inherent to that particular soil type. If a soil is low in boron, the food grown there is likely to be low in boron. If a soil is high in iron, the food is likely to be higher in iron than food grown in iron deficient soils. There is a direct correlation between the nutrients in the soil and the nutrients in your food grown from that soil regardless of whether that farmland is organic or conventional.

Some folks will say "well organic farmers take better care of their soils with organic practices." Let's take a closer look at that premise...

Wikepedia defines organic farming as "uses a variety of methods to improve soil fertility, including crop rotation, cover cropping, reduced tillage, and application of compost. By reducing tillage, soil is not inverted and exposed to air; less carbon is lost to the atmosphere resulting in more soil organic carbon. This has an added benefit of carbon sequestration which can reduce green house gases and aid in reversing climate change."

Jeez, sounds like my farm... which is conventional...

OK, let's look at those practices:

Crop rotation - yup we do that. We do that so that we build up the soils and reduce the likelihood of pest resistance by repeatedly planting the same thing in the same field year after year.

See this field of edible/tofu soybeans? Last year it was planted in corn.

Next year it will be back in corn or hay or tomatoes or green beans. We rotate our crops annually. Always have. Always will. Period. Conventionally.

Green manures & cover crops - yup, we do have and have for 40+ years.

Typically we plant cover crop wheat or rye. If we are looking to build up our soil fertility and tilth, we plant a mix of Austrian snowpeas, rapeseed, and crimson clover. If we are looking to break up compaction and tight soils, we plant tillage radish which you may also know as the Japanese delicacy Daikon radish. My husband says tillage radishes produce the most "mellow" soil. That's farmer terminology for really good soil quality. We plant the type of cover crops and green manures that the soil tells us it needs. Always have. Always will. Period. Conventionally.

No-till/conservation till - yup, we do that.

Good gosh this picture is older than I am and what a cutting edge contraption it was in its day. As I said in my last blog, this was a HiBoy cover crop seeder for no till planting. A practice started nearly 2 generations ago on our farm.

In this more current picture above is of the Comptroller of Maryland getting his first lesson in tractor driving, pulling a No-till ripper. He came for a visit so we taught him how to drive a tractor. No-till ripping is a conservation practice that breaks up the soil compaction 12+ inches below the surface with  minimal surface soil disturbance. Disturbing the soil surface creates the conditions for erosion. As land stewards, we want to keep our soil intact and in place so we do as little cultivation and tillage as possible.

Integrated Pest Management - yup we do that.

IPM is simple common sense practice. Essentially, you scout a crop looking for pests, whether insects or mildew or disease. IPM means you look for a certain level of disease or pest, also known as a threshold, choosing not to treat the problem if its below a certain threshold, or treating the problem if it reaches a higher threshold. Here my husband Hans is scouting soybeans looking for ear worms and stink bugs both of which attack the soybean pod and damage the crop. When we choose to spray, we may use an organic pesticide, or we may use a synthetic pesticide, it all depends on the level of the problem and the best way to correct the problem. When we do spray, we spray judiciously, using EPA approved organic or synthetic chemicals according to their label and making sure that the proper pre-harvest interval is followed so that no excess pesticide residue from either the organic or synthetic chemicals we use, remains on the crop.

So back to the food fight. We as conventional farmers practice very similarly to organic farmers. It is our goal to be constantly improving our soils through the many practices that are often credited to "organic" farming systems. We adhere to the pre-harvest intervals so that our buyers can trust the foods that we grow do not have unsafe levels of residues. As I've said in numerous blogs, my kids eat what we grow, and they are of utmost importance to me. If I wasn't comfortable feeding them what we grow, then we wouldn't farm the way we do.

There is not a food fight between us as farmers. We have good friends and neighbors who are certified organic. We all get along which is why it amazes me that this choice between organic and conventional is so polarized amongst consumers. As a farmer, I want you to support farmers of all kinds. If you choose organic foods, your supporting a farmer. If you choose conventional foods, your supporting a farmer. As a dietitian, I want you to eat healthy foods and know that you can do so from both organic and conventional. Despite the media frenzy around the study, I don't think this really is a food fight. It is your choice as a consumer and we are fortunate to have as many safe and healthy food choices as we do thanks to all the American farmers, organic and conventional.

Every Day is Earth Day On Our Family Farm

My daughter is great about asking questions that lead me to blog. (Remember, she was the one who ask about green french fries?) Today after church she says, "Mom, its Earth Day, why didn't we celebrate?" My response? "Honey, we're farmers, we celebrate Earth Day every day!"

OK, so that sounds rather corny, but really, that's the way it happened.

So let me tell you why our farm celebrates Earth Day every day. As stewards of the land, we have numerous farming practices that preserve and improve our soils and protect our environment.

Let me share some of our conservation efforts with you:

1. Our farm voluntarily took over 100 acres of farm land out of production and put them into conservation practices. These acres are adjacent to woods, ditches, ponds, waterways, and streams. This leads to less sediment and nutrients from getting into the water. It takes sensitive acres and takes them out of production protecting the larger environment around them. Not only does it improve water quality, but it also provides enhanced habitat for wildlife.

2. We installed grassy waterways and buffers larger than required. This enhances filtration of the water through the field to a wider buffer and further limits the likelihood of nutrients reaching the waterway.

3. Part of our farm is across from the town cemetery. The corner of that field is very low ground and not productive. We planted it in wildflowers and warm season grasses which when in bloom, will be free for the picking.

4. We take tissue samples of our crop foliage to determine the nutrient status of the crops (sort of like you getting a blood draw at the doctor's to check your cholesterol and other health indicators). This allows us to prescribe a "diet" for the crop that it needs, no more, no less. It allows us to target certain nutrients the plant needs. While many people take a multi-vitamin "just in case" (which by the way leads to higher nutrients in the water too), we feed a specific diet to our crops based on the results of the plant tissue analysis.

5. I have previously blogged about our new "GreenSeeker" technology. We used this technology recently in our small grains (wheat and barley). The GreenSeeker detects the chlorophyll in the plant tissue and tells us what the nitrogen needs of the plant are. We reduced our nitrogen application by 7-15 pounds per acre using this technology. This application is called "variable rate" meaning the technology senses when less is needed and cuts down on the amount of fertilizer applied as you travel across the field. This may not seem like alot of savings in fertilizer, but when you add it together with the total number of acres, it is quite a savings in the total amount of fertilizer applied.

6. RTK is an auto-steering system that we have in our tractors. The Earth Day advantage of RTK is that it guides our equipment with "sub-inch" accuracy, virtually eliminating all overlap in seed and fertilizer applications and preserving precious resources and enhancing our environmental control systems.

7. Cover crops are probably our largest contribution to land stewardship and therefore Earth Day. These are often called "green manure". We put over 1000 acres under cover in the winter. Cover crops are planted in the fall and are designed to take up any left over nutrients remaining in the soil after the previous crop is harvested. Instead of just leaving the field fallow for the winter, cover crops bind the nutrients and immobilize them in the plant. When we burn down the cover crop in the spring, those nutrients become available to the spring crop that we are currently planting.

8. No - Till is probably our second largest contribution to land stewardship and Mother Earth. 90% of our land is not worked up at all and the other 10% is either in permanent perenial crop such as the vineyard or we use conservation tillage equipment to prepare the soil. Using no-till, we do not work the ground up but plant directly into the plant residue left over from the previous crop. The Earth Day advantage of no-till farming is that you do not expose the soil to the risk of erosion.

So Happy Earth Day! Our family farm is celebrating it by continuing to be good stewards of the land we have, doing all that we can to leave it in better condition for the next generation.