BIG YIELDS REQUIRE GOOD FERTILITY…
Eight to ten tons per acre alfalfa yields are possible with precision management, but pay attention to fertilizer practices and use good alfalfa soils. These research data show the high nutrient demands of the crop.
Nutrient demand varies from one location to another depending on soil type, variety used, soil test levels, and – most importantly – yield level. Observe the nutrient removal of alfalfa over a six-year period for farmers in the Pennsylvania Alfalfa Growers Program
Note how nutrient removal rises rapidly with yields. Compare the removal figures with those in the previous table. While location can make a difference, high yielding alfalfa still demands high amounts of nutrients.
™ provides the grower with vital elements for use in a complete program to increase yields and crop quality. We stress the importance of balancing the soil as opposed to just feeding the plant.
The most accurate way to determine the condition and needs of your soil is through soil testing. We offer soil testing services to our customers through prominent soil testing laboratories. To balance major mineral imbalances we recommend the use of natural materials for long term corrections.
BREAKDOWN OF NUTRIENTS FOR ALFALFA
Phosphorus (P) is important for early growth, cell division, all metabolic energy transfers, and the formation of carbohydrates and proteins. Eight to ten tons per acre alfalfa yields remove 12.5 to 15 lbs. per ton of P2O5. Phosphorus moves very little in the soil and has a tendency to become fixed. This means plenty of Phosphorus must be available throughout the rooting zone to avoid Phosphorus shortages. Shortages are likely to occur:
● During early growth when alfalfa roots are small
● During periods of drought when part of the rooting zone may be inactive
● During cool periods when Phosphorus uptake is less
Alfalfa requires larger amounts of Potassium (K) than any other nutrient, from the soil or from fertilizer. In higher yield alfalfa systems, the crop is cut more frequently and harvested at a younger growth stage.
This leads to higher Potassium concentrations in the harvested forage and much greater Potassium removal than once considered adequate. Removal data for intensively managed alfalfa suggest each ton of hay harvested will remove from 55 to 75 lbs. Potassium. That is 10 to 30 lbs. per ton more than considered adequate a few years ago.
Phosphorus (P) and Potassium (K) are a vital team to alfalfa stand life. Many studies, especially with Potassium, show thicker stands, fewer weeds, less heaving and winterkill and more root development as soil Potassium and Phosphorus levels increase.
Like Phosphorus, the Potassium soil test level should be built up to the high level before establishment. Apply 60 lbs. K2O per ton of yield goal. Split Potassium applications increase fertilizer efficiency and availability throughout the growing season. A good program is to apply half the Potassium after first harvest and the remainder after the next to last harvest in fall.
Sulfur (S) has emerged as a major nutrient requirement for big alfalfa yields with 4.5 to 6.5 lbs. per ton being removed. Sulfur is important in nitrogen fixation and in nitrogen metabolism processes. Thus, it is essential for protein level and high quality alfalfa feed. The nitrogen to sulfur ratio (N:S) in alfalfa tissue is considered to be an important diagnostic tool in producing a high yielding, high quality crop. The optimum ratio is 11:1.
Like with major nutrients, micronutrient removal increases with yield. As a precision manager, you should monitor micronutrient levels in your soil and crop to keep them from becoming limiting production factors. Boron (B) is the micronutrient most likely to limit yields. Compare the Boron removal in high yields to the standard at lower yield levels.
PUTTING IT ALL TOGETHER
Precision managers know that adequate fertility alone cannot produce big yields. It takes all growth factors working together to get the job done.
question is: Do big yields pay? Precision managers know the answer is yes and
they know they must consider all interacting factors in modern alfalfa
production. Compare the returns for
Plan a total production system using high yield goals and adequate fertilization. It is the best way to beat those ever-rising production costs…the best way to maximum economic yields.