Why Do We Farm The Way We Do?

By: Bryant Spivey, County Extension Director
Johnston County Cooperative Extension Service

As you travel the rural roads of Johnston County this time of year you will see many tractors running in the field tilling and bedding land. Some readers may not understand the terminology bedding, so I will explain.

Beds are created in the soil for many different types of plants.  Landscapers and homeowners often speak about creating “raised beds,” and this is essentially the same thing that farmers are doing in the field.  A raised bed results in warmer soil temperatures and good drainage which provides an excellent environment for plant roots and early crops.  So, farmers create beds to provide soil drainage, aeration, and warm temperatures for crop roots to develop and proliferate.

Some may ask, “Why don’t we use conservation tillage or even no-till planting for some of the crops that we grow?” Well, we do use conservation tillage commonly for crops like soybeans, cotton, corn, and even peanuts, and wheat. For all of these crops growers have access to excellent herbicide options to control weeds and this greatly reduces the need for tillage.

In addition, in most seasons we can plant, grow, and harvest those crops in a timely manner in our environmental conditions.  However, with tobacco and sweet potatoes, growers have very limited herbicide options in their toolbox, season-long weed control is critical, and neither of the crops is highly competitive with weeds.

Therefore, farmers employ in-crop cultivation to control and manage weeds as well as establish a high and wide row ridge.  For most field crops, in-crop cultivation is a thing of the past but not for tobacco and sweet potato.

You may even notice that farmers leave out portions of fields, especially when planting tobacco. This is because tobacco is very sensitive to wet soils and can quickly drown in wet conditions.  Drowned tobacco is caused by low oxygen in the root zone resulting in root death and rapid wilting.  Drowning is very detrimental to crop health, yield, and quality.

In addition, many of our soils in the coastal plain of North Carolina are prone to tillage/traffic pans.  These hard pans form in what is called the “E horizon,” a sandy, low organic matter, light-colored layer that is just below the topsoil and just above the clay layer.  This layer is often so hard that plant roots are unable to penetrate it to access the moisture and nutrients that are stored in the clay subsoil.

In order to address this problem, farmers in the coastal plain use deep tillage from narrow “subsoiler” shanks to shatter the hard soil layer and allow an entry point for roots.  This practice means that plants perform much better when dry conditions arrive in the growing season.

So, when we consider the question of, “Why do we do farm the way that we do?” it is because of the crops that we grow and proven practices to produce high yields of quality products.  In spite of needing this tillage, farmers also use cover crops, grassed waterways, field borders, and wind breaks to protect soil and they carefully contour rows on sloping sites to direct water flow and protect the soil.