The planting season is here and a lot of farmers are facing limited financing and poor justification for this crop. I know that may sound like I am double-speaking but what I want to express is that so many farmers have limited financial “depth” and prices do not justify the level of production cost they have been accustomed to in recent years.
At the same time we have to face the reality that the best way to reduce the cost of each bale of cotton or bushel of grain is to produce more per acre. Somehow we need to determine where the maximum return for each dollar might be. Economists are not the only people who use the total product curve. They normally looks at input in terms of financial commitment to an enterprise while the same principle can be applied to amounts of seed, fertilizers, fuel, hours of labor, etc.
This is the reason you hear people like me talking about things like plant populations, fertilizer rates, trips over the field, threshold levels for insect and disease applications, etc. We are trying to help growers avoid those unnecessary things that add cost to a crop without producing a justifiable increase in yield.
The influence that each form of input has on final yield and profitability is subject to being altered negatively or positively by many factors such as weather, planting date, soil type, crop variety, existing soil fertility factors, and others. We have to deal with these issues individually as the crop is established and managed. Each one has its own set of criteria that influence the decisions that must be made about it.
For corn on dryland silt loam/sandy loam fields in Central Mississippi a final population in the 24 to 26 thousand range has been proven capable of maximum yield so we need to plant about ten percent more to end up there. For soybeans in similar conditions the “sweet spot” in most cases falls around 90 to 110 thousand plants per acre. Since soybean seed quality is not usually as consistent as corn we probably need to plant 20 percent more seed to end up there.
In soil fertility the first issue is soil pH. When this this factor is where it should be we can usually supply nutrients in amounts a little above the actual removal for a reasonable yield goal. P and K should be applied in spring at or after planting on our silt loam/sandy loam soils.
Those who have applied poultry litter recently probably have adequate phosphorus (P) and may only need supplemental potash (K). Remember to include zinc (Zn) for corn and sulfur (S) according to the soil test recommendation. A recent soil test should guide every input in soil fertility.
Some of the very silty or sandy soils may benefit from split applications of N and possibly K as well if soil test levels are low. Don’t cut N rates for corn if at all possible, and don’t overdose N on cotton.
The best rate of N for corn is around 1.2 pounds of actual N per bushel of expected yield, and the best rate of N for cotton will be around 80 pounds per acre of actual N in most situations unless the soil has a high clay content. Higher clay soils may need an additional 10 to 20 pounds. For soybeans apply at least an estimated removal level of P, K, and S.
When it comes to pest management, we can’t continue treating when threshold levels are not present. In most cases we can produce profitable yields with fewer applications than we have made in the past. How you do that is something I will stay away from today.
We all know that reduced tillage saves trips but it also conserves moisture and nutrients that we will likely need to finish the crop. Fewer trips means less fuel and equipment needs and fewer payroll checks to write. I have already seen far more corn stand failures in freshly prepared soil than in stale soil. Unless the field was flooded for an extended period the seed germinated and emerged in most no-till fields.