Many reference the Albrecht papers but it seems few have read them, which is distinctly unfortunate, considering he pioneered many of the soil nutrition management guidelines that are still used today, a hundred years later.
When we manage applied fertilizers and amendments, it is very important to consider the nutrient release curves, and time applications so we have the greatest nutrient release at the moment of peak crop demand. Nutrient release curves should dictate whether a product is applied in fall, spring, or after planting.
Of course, when we have abundant organic matter and functional biology delivering all of the crop’s nutrition requirements as the system was designed to function, such close management finesse is no longer required. William Albrecht described this first:
Organic matter – the “constitution” of the soils1
The most neglected and most important chemo-dynamic factor of the soil is the organic matter. Organic matter may be said to be the constitution of the soil. As a definition of the word constitution in that usage, we take its meaning when the doctor consoles the friends of a patient in serious illness by reminding them that the patient has a good constitution. According to its meaning, as used in medical practice, a good constitution is the capacity of the individual to survive in spite of the doctors rather than because of them. The organic matter in the soil has been the capacity for our soils and our crops to survive in spite of the soil doctors, rather than because of them.
Your attention has already been called to the importance of the organic molecule when it is on the clay. There is also the tremendous significance of the organic matter as a season’s release of plant nutrition. This release is timed to increase during the growing season or become larger as the temperature goes higher. The microbial activities follow Vant Hoff’s law and double their rate of decay of the organic residues with every 10° rise in centigrade temperature. Nature has always been fertilizing with the organic matter which is dropped back to the soil from the previous plant generations which have died in place. Organic matter is still the most reliable fertilizer in terms of the nutrient ratios and of the time when maximums must be delivered.
Another aspect of organic matter about which we probably haven’t thought much is the value of some organic compounds in cycle, that is they may be dropped back as crop residues and the next crops roots may be taking them up, using them and dropping them back again. Plants need the various ring compounds in very small amounts to make some of the essential amino acids. They need the phenol ring in phenylalanine, one of the essential amino acids, essential for plant growth as well as for animals and ourselves. They need the indole ring, which is a phenol ring plus a side ring. It is the compound which gives the odor to feces when the digestion acts on the tryptophan of which that ring is a part. Tryptophan is the most commonly deficient amino acid, and is one of marked complexity.
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