Agriculture 'Wonder' Products
Wonder products are seldom worthless but usually are not worth their cost for the effect that they may or may not have. Often they are sold with scientific sounding promotion and promise incredible benefits that are not directly substantiated. A typical promoted effects is a reduction of fertilizer application. However, soil fertility is often high in potato crop land, and fertilizer application can be reduced even without the wonder product. Another pitch similar to the old "snake oils" is that the product is a "cure all' for practically all soils and crops. Advertising and sales are usually built entirely on testimonials or anecdotes. Actual, objective data supporting the claims are lacking or taken out of context. Often claims of results are based on visual observations showing an obvious effect of the product. In my experience, this has occurred when the ingredients of the product are not disclosed but the odor clearly indicated the presence of urea which is known to cause a temporary greening of foliage.
So, beware of products claiming:
- Increased soil water-holding capacity,
- Increased soil aeration,
- Increased nutrient-holding capacity or availability,
- Improved soil structure or stability,
- Increased microbial activity,
- Improved uptake of organic matter,
- Increased pest resistance,
- Increased water penetration,
- Improved water-use efficiency or lower evaporation,
- Improved root respiration,
Types of Wonder Products:
Soil additives are claimed to reduce or supplement fertilization. Often they contain trace elements and report the total amount present. This may not indicate their availability to the plant, and the soil often naturally has more of the elements then the product.
Soil amendments are claimed to improve the physical or chemical properties of the soil. Changing soil structure, soil texture, pore capacity, aeration, or water-holding capacity is just about impossible and would require massive amounts of amendments. A simple and not uncommon example is lowering soil pH with tons of elemental sulfur per acre. Adding even several pounds would make an infinitesimal change.
Microbial inoculants supposedly increase populations or stimulate activity. The amount of contribution of these inoculants is infinitesimal compared to the actual natural population already in the soil. Some products were pasteurized for shipping and handling, and so any organisms are actually dead. Note: these products should not be confused with nitrogen-fixing bacteria, Rhizobia spp., used in legume agriculture which are well-documented in science.
Soil humus, humic acid and fulvic acid are terms used for mineral organic matter products and are classed as humates. They are claimed to increase soil levels and activity of soil organic matter. Soil humus is composed of a lot of compounds ranging from known biochemicals to polyelectrolytes resulting from dead microbes. These products would have little effect on the soil. For example, soil containing 3% organic matter has 60,000 lb organic matter per acre at furrow depth. Adding 500 lb of a commercial humate containing 60% organic matter will increase the soil's organic content to 3.03%.
Plant growth regulators (PGR) are well documented to affect plant growth and many are natural hormones found in the plant. They can have both a beneficial and a harmful affect on plants depending on dose and application timing. Examples are gibberellic acid for potato sprout promotion, maleic hydrazide for sprout inhibition, and 2,4-D for weed control. Some wonder products may contain some real PGRs. However, PGRs have very defined specific uses and applying them to the soil is NOT one of them. In 40 years of research on PGRs, I have never come across one or combination of PGRs that is active when applied to the soil. To have an effect, PGRs need to be applied to living plant tissue, seed, tuber, stem, leaves, root, flower, fruit, etc. Examples of PGRs in agriculture are auxins such as 2,4-D and dicamba, cytokinins such as kinetin, gibberellins such as gibberellic acid (GA3), and ethylene, a gas.
Wonder products or "soil medicines" can not ever substitute or supplement good agronomic practices. So, buyer beware.
Reference: McDole, R.E. and C.G. Painter. 1979. Wonder Products in Agriculture. U. Idaho CIS #510.