Free Nitrogen

Economic crisis or not, we generally like to get things "free." Sometimes there are strings attached and what appears to be free is not such a great deal. Among the thousands of natural phenomena, there are some amazing processes that give us "free" products. The process of photosynthesis is an example. It includes the use of free carbon dioxide, free sun energy, and free rain, all working in connection with a lot of natural minerals. The result is system that makes our food. It can work just fine without any input from us. I guess it is our nature, but we have a tendency to want to control the processes and take credit for things that come naturally.

We know that plants need nitrogen for growing. The nitrogen used by plants does not all come from the soil. The air is 75 percent nitrogen and plants utilize some of it on routine basis. It actually moves into the plant through the stomata, just as does the carbon dioxide. Beyond using the atmospheric nitrogen for growth, some plants are able to take that nitrogen and "fix" it in the soil. The biggest group of nitrogen fixing plants comes from the legume family, which includes peas, beans, peanuts, vetch, black locust trees, and many more.

The nitrogen fixation process is actually a little more complex in that it requires the help of Rhizobium bacteria, which are found naturally in the soil. Caution! Soils that that have had a lot of abuse through the use of high salt fertilizers and pesticides may not contain the necessary bacteria. Without the bacteria, no nitrogen will be fixed. Fortunately, you can purchase the bacteria to re-inoculate bacteria-deficient soils.

I use Austrian winter peas as one of my primary winter cover crops. I plant the peas in September and they grow about 12 inches tall in the fall and then begin to grow again in the spring. By early May they are 2 feet tall and beginning to flower. When they begin to bloom, I cut them off and either leave them right in place for garden mulch, or use them for compost, or sometimes feed them to my red wiggler worms. Corn is heavy user of nitrogen and does very well where the peas have grown.

I dig up some pea plants each fall and spring to see if they are producing nitrogen. The presence of nitrogen is easily detected by the whitish-pink nodules on the roots. The amount of nitrogen that is being "fixed" in my garden appears to be growing each year. The peas are profusely loaded with nodules this spring. I expect there is 100 - 200 pounds of nitrogen per acre on the roots. The picture below with the Austrian winter peas and the nodules show just how the nitrogen fixing system works.

In addition to the accumulation of nitrogen on the roots, the biomass of the vegetation is huge. I weighed a sample of the Austrian winter peas from my garden and estimate that I have 13 tons of organic matter (green weight) per acre. Our farming ancestors knew the value of nitrogen fixing cover crops, crop rotations, green manures, and other similar systems. The same is true of many current alternative and organic gardeners/farmers, the Amish, and others. These are the practices that lead to more sustainable farming.

The real plus in the cover crop-rotational system is that the nitrogen produced in this way is in an organic form and is released slowly, often just the way the plant needs it. It's another example of how important it is to understanding the workings of Nature. This "free" nitrogen story is about as good as it gets in Nature.

Tuning in to Nature

Tuning In To Nature is the title of a book by Philip S. Callahan, Ph.D. (a University of Arkansas grad). The book is about infrared radiation and insect communication systems, and it deals with how insects are equipped to search out and attack weak plants. The plants emit specific electromagnetic radiation frequencies and certain insects are tuned in and attracted to those plants. Those antennae on the male cercropia moth (shown below) are not there for decoration, but for the functional sensing. This whole concept is a logical step from what starts as one of the Laws of Nature. Stated succinctly, this Law says "The Default Position in Nature is Health." Putting it another way, "Plants are Designed to be Healthy."

So how does that Law fit with insects and disease? Is it insects and disease that cause plants to be unhealthy? No. Plants are unhealthy because of stress caused by toxins or by mineral/biological deficiencies, which are generally soil problems. Excess minerals can also act as toxins. With that stated, it makes sense that insect and disease are the symptoms, not the problems. In fact, the corollary to the Law is this: "Insects and disease are the Appropriate Response to the Existing Conditions." They are the garbage collectors, the cleanup crew, appropriately taking care of the weak and waste in biological systems. When we approach the growing of plants in this manner, we tune in to nature and begin to cooperate with nature rather than try to control it.

The take home, practical lesson from understanding this is very simple. Apply the Hippocratic oath: "First, do no harm." In practice, first and foremost, don't apply toxins to the plants or the soil. Second, strive to fix the soil mineral/biological deficiency conditions. We can see what happens if we do otherwise. By applying toxins (chemical pesticides), the plant/soil system is weakened and insects and disease appears. So then we apply more chemicals (toxins) to kill the insects and pathogens, and the vicious, downward cycle continues. It's what many folks in alternative agriculture refer to as rescue chemistry. There are thousands of acres under alternative systems to demonstrate that farming/gardening does not have to be done that way.

The insect and disease phenomenon, as described above, is one example where organic and conventional garden/farming are viewed differently. I know from much experience that the concept is new to many gardeners. If it strikes you as a new idea and different from how you have always viewed insects and diseases, I hope you give the topic some study and thought. Take some time to digest the significance. It is a well accepted concept in the eco-agriculture arena, the place where gentle-on-the-land, low input, and sustainable farming practices abound.

More than ever before, I am getting questions about how to get started in organic gardening. I suggest, that even without knowing all things you need to do, make a commitment and begin. Vow to NOT use the pesticides and chemical fertilizers. Next, start concentrating on creating a healthy soil. That may involve compost, raised beds, minimum tillage, cover crops, and natural fertilizers. The important thing is to get started. We have all made some mistakes, and will make more in the future, but do not let that deter you. One thing is certain. If you stick with it, the organic adventure will serve you and society very well. You will be surprised how you can improve your soil in a few short years. Ask me for advice if you need it.