Commercial farmers are always faced with questions about best investments for their hard earned dollars. The crop and dairy situation in 2007 may actually have improved that situation. There may be more cash flow to consider for investment. It is easy to invest in steel and structures. New tractors, planters, combines and buildings are obvious and create a pride of ownership.
My opinions may be biased as an agronomist, but what about those unseen investments of drainage, lime and soil fertility?
Drainage: A combination of subsurface drainage and outlet improvements can regularly boost yields by 5 tons per acre of corn silage, 25 to 35 bushels per acre of shelled corn and over 1 ton per acre of dry hay. This is based on data collected in research trials in the 1970’s. Five tons of corn silage is easily worth $125. This is likely to pay for itself in one year.
Soil drainage improvements can change a soil type by one classification unit. In other words, a “somewhat poorly” drained soil type can be moved up to a “moderately well” drained soil type. The improvement in timeliness of field operations means greater efficiency for you. The reduction in time that root zones are saturated and anaerobic means improved root/plant growth. If improvements in productivity are your goal, improved drainage can be the best return investment.
The time to evaluate where additional drainage is needed is anytime rainfall exceeds infiltration. Put on your boots and walk the fields after a rain. Note where the water is flowing, where it is accumulating and where it reaches outlets. Experience is also a great teacher. You know where equipment has been “stuck”. Make a hand drawn map/sketch. Then contact your local SWCD or land improvement contractor to design and lay out a drainage plan.
Drainage also improves land values. An old rule of thumb is that half the cost of drainage improvements becomes reflected in land values. Improved drainage increases management alternatives on the soil. In today’s dairy and crop economy, where high commands a premium, it is worth more than ever.

Lime: It really should be called “soil pH adjustment”, but “liming” is the common term. If soils are in need of lime to improve soil pH, a positive response is always the outcome. On acid soils, liming has many benefits to soil health.
The easiest way to know lime needs is through soil testing. Most of the crops grown in New York make optimum growth in a root environment where the pH is between 6.0 and 7.0. A pH of 7.0 is neutral, lower is acid and higher is alkaline. Chemically, pH is not measured on a linear scale, but on a logarithmic scale. Thus a pH of 5.9 is 10 times more acid than a pH of 6.9. A pH of 4.9 would be 100 times more acid than pH 6.9. Some soils have much greater buffer capacity than others. That means more lime is needed to accomplish the same change in soil pH. A gravelly or sandy soil will require much less lime to improve pH than a silty clay loam soil.
The Cornell Soil Testing system takes this into account. It measures soil pH plus exchangeable acidity or buffer capacity. The recommendations consider both pH and buffer capacity any time the soil test is 6.0 or lower.
Liming needs are also tailored to the crop rotation. Not all crops require a soil pH of 7.0. If there are no high pH crops (like alfalfa) listed in the three years prior or forward, then the recommendations are adjusted to the highest pH requiring crop, not to 7.0. Liming is also the easiest, lowest cost way of improving the available Calcium and/or Magnesium level in the soil.
Other benefits of liming include improved fertilizer efficiency, improved biological activity in the soil (earthworms, bacteria, fungi) and improved herbicide effectiveness. Nitrogen fertilizers are poorly converted (by soil bacteria) in soils with pH below 5.6. If nitrogen fertilizers are not converted to nitrates, they do not move across the cell wall and into plant roots. Phosphorus fertilizers undergo a chemical process called “fixation” in acid soils and are much less available to plant roots. Liming “frees up” fixed phosphorus in acid soils, especially those with high clay content. Raising the soil pH from 5.2 to 6.2 is like finding free fertilizer. It will pay for the cost of ag lime.
The bottom line is that soil testing should be one of the first investments. If lime is needed, it should be the first plant nutrient investment.
Fertilizers/soil fertility: For optimum production and return on investment, fertilizer planning should involve fertilizing the crop rather than the soil. There is substantial data from Dr. William Cox’s work at the Musgrave Research Farm to show that soil fertility has great buffer capacity. In his trials (over several years), nutrients were applied at Cornell Soil Test recommended rates plus 2x and 3x rates. Even in the plots that were irrigated to maximize yields, the recommended fertilizer rates gave optimum yields. This was done on continuous crop soils that had not received animal manure.
Recent work by Dr. Quirrine Ketterings and our work in the Conesus Lake Watershed have shown that current recommended phosphorus rates may be too high. This is definitely the case on farms where dairy or livestock manure is a regular part of the rotation. In these situations, it is rare to have a response to phosphorus beyond 10 to 20 pounds per acre as a band application.
If soil test results show low soil fertility, following recommendations that give optimum crop responses will gradually boost soil test values. Long term, soil fertility is a good investment. In the short term, fertilize for maximum economic yields.
No glamour: Neither drainage nor lime get much attention in terms of farm input marketing. You probably never had a salesman come to your farm who was selling drainage. Likewise, lime is marketed mostly on a request basis. So, if these are the investments needed on your farm, it is up to you. Make the decision. Call the shots. Get the job done. Then talk to the equipment or fertilizer sales representative after you have made those “unseen investments”.
Another unseen investment is in your own education and skills as a manager or leader. You set the tone for your farm. Setting high standards and improving your managerial skills will have a ripple effect on those around you.
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