Written by Mike Hamilton, CCA & President of Turf Dietitian
With an array of designer products and new chemistries available, making decisions on what products to apply to your turf can be intimidating. Through years of experience working with golf courses and superintendents, we have identified the main reason for these concerns being that you simply want your
product to work for your unique conditions and environment and must take into account several factors such as:
- Shrinking budgets
- Plant and soil health
- Product efficiency
Without a doubt, most of our conversations around product selection will go something like this:
Client: “I’m using product X, is it a good product for me to use?”
Us: “Why are you using the product?”
90% of the time the answer is: “My salesman convinced me I needed it.”
We get it, we used to do the same as superintendents. Who really has the time to research every new product, right? In reality if your salesman hasn’t carefully analyzed your unique factors, such as:
- Physical properties
- Environmental factors
- Plant tissue
He or she is just crossing fingers and hoping for the best. A product may be great in general, but it may not work for your situation specifically.
We are increasingly receiving calls from Superintendents asking which company’s designer products are better. What we find is that many products we compare are practically identical because they contain the same chemical compounds.
When we are asked which company’s products are the best, we will research them to try and get an answer. However, 95% of the time we tell you to use the company you trust the most and know will give you great service. Occasionally we will discover a new technology from one of our customers or manufacturers.
We never immediately refer the science for two simple reasons: Firstly, just because it’s working at one golf course, it doesn’t mean it will work at all of them. Secondly, we like to run our own trials to make the decision for ourselves based on the results we see. We set up trials and collect data for 3 to 4 months to identify the product’s efficiency. If we see consistent positive data, we will start recommending the science to our customers who would benefit from the technology.
Most of the confusion with regard to product comparison comes from the many different chemistries being introduced to you by dozens of different companies, all of which claim their product is the best.
The science behind all the products discussed below is sound, but it doesn’t mean you need to use all of them. When your budget is tight, it gets hard to determine which of the sciences will be most rewarding for your course. The only way you can know for sure which of these products you need to incorporate or not use is to gather detailed data.
What type of data do you need?
- Irrigation water
- Physical soil structure
- Soil reserve
- Soil solution
- Nutrient consumption
- Physical factors
Once you’ve collected and interpreted all the data on each of these factors, you can make a logical determination of which sciences are most essential for you to use. Alternatively, if you would like to take an easier route, call Turf Dietitian and we will do all the legwork for you.
Here are the chemistries I will review
- Organic Acids (humic, fulvic, amino)
- Mineral Acids (citric, sulfuric, hydrochloric)
- Plant growth hormones
Organic acids are used in the turf industry to chelate and hold nutrients in the root-zone longer, build CEC, supply nutrients to the plant root, and add carbon to the soil. The main organic acids I see used in the turf industry are fulvic, humic, and amino acid.
Organic Acids (OA) are weak acids that do not completely break down in water (slightly insoluble). Most OA is formed as microbes and plant material decompose. The amount and type of acid being produced is strongly
dependent on factors like type of organic matter, oxygen content, soil structure, water infiltration rates, and product pH. The higher the pH of an acid, the weaker it is.
Fulvic and Humic Acids
Both fulvic and humic acid function as expected, however, fulvic acid has a higher pH and is therefore weaker than humic acid. Fulvic products tend to occupy the root-zone for about 2 weeks. Humic products, on the other hand will stay in the root-zone for about one month. Using a combination of the two acids gives you a slow release and a medium release of nutrients to the soil solution. The concern with fulvic and humic is the insoluble fraction of the molecule, and where it goes. Insoluble compounds cause soil deterioration.
Not all OA’s have a low pH which can cause future issues by inhabiting the soil for years and causing layering which will obstruct water infiltration. Majority of the stronger organic acids are sold as a granular and are often used during the aerification process. If you use a granular OA product, it should be a priority for you to soil test frequently (minimum of 4 times per year) and inspect the entire soil profile regularly. Weaker acids also need frequent monitoring, because too much OA in the soil becomes counterproductive.
When are organic acids a good product for you to use? Use organic acid when you have sandy soil with low organic levels and CEC and high-water infiltration. Once soils begin to develop more organic matter, you should lower your rates exponentially. At some point it’s simply not necessary to use organic acids. We wouldn’t recommend OA when the organic matter is 2.5 or higher, CEC above 6, or when the saturation index is above 50%.
To determine which company has the best organic acid product, you simply need to look at the percentage of acid and the cost per gallon of active ingredient.
Amino acid, in my opinion, is nature’s perfect acid despite its complexity.
As we all know, amino acids are building blocks for proteins inside of the plant. Amino acids in soil are great natural chelators because of their near neutral pH, and low molecular weight (small molecule that can easily enter the plant). However, in the soil they are unstable, quickly leachable and its difficult to determine how to efficiently use them for plant health.
When a plant takes in an amino acid chelate, it uses both the amino acid and the nutrient. Some soil product chelating agents (EDTA) are waste material once inside the plant, and the plant needs to use energy to dispose of the waste.
Here’s where amino acids get complicated. In their natural form, amino acids are a perfect balance of acid and basic amino groups, the balance gives it a neutral charge. As soil pHs change due to either acids or alkalis inputs, it changes the acid from a neutral charge to a positive or negative charge. If you increase the pH of a solution, the amino acid will take on positive charge. If you decrease the pH of a solution, the amino acid will take on negative a positive charge.
In the soil amino acids can rapidly change their charge with any type of input. Due to the continual change in the soil’s environment, it’s difficult to predict the characteristic of the amino compound. This is important to understand when deciding to use amino acids in your program to obtain maximum application efficiency.
I believe every golf course would benefit from using amino acids. However, keep in mind that the science behind using amino acids as a supplement is still relatively new. The science hasn’t advanced enough to know which amino’s are most essential, what balances are most optimum for plant health, target ranges for each amino acid, and if there is a level that is counterproductive to plant health.
There are 3 ways you can use amino acid in your programs:
- As a soil product
- As a foliar chelate
- As a straight amino acid blend
My belief is that using an amino acid product as a soil amendment is the least effective method due to the instability in the soil. Furthermore, as dead plant material and microbes decompose, amino acids return to the soil. In my opinion, the best results come from spraying the leaf with the amino acid. Amino acids are tiny molecules, therefore they free flow into the plant when they are applied to the plant tissue. Spraying them on the plant gives you more control over the charge of the molecule.
If you cut the turf at less than 1/2” tall, it will not produce enough internal amino acids on its own. For that reason, I believe that every golf course would benefit from the use of amino acids. However, it will take more effort on your part to prepare the product to spray.
You actually have the ability to change the charge of the amino to favor cation or anion uptake by buffering the spray water. To get maximum efficiency from amino acids, you must know the pH of the product you’re applying. If you’re applying straight amino acids with other nutritional products in the tank, you can adjust the pH of the water to favor either cation or anion uptake. Before you put the product in the plant, you need to adjust the water supply and then pour the product in at the end. Let’s say the plant needs potassium and magnesium and the pH of the product you’re using is 6.8 – here’s what you need to do: buffer the water down to 6 and you will get a better uptake of cations.
If you’re spraying a nutrient chelated with an amino acid, it’s very important to keep the tank water pH identical to the product being used. If an individual nutrient is chelated with an amino acid, it’s already charged correctly. If the pH of the tank water moves in the wrong direction, the nutrient you are applying may never end up in the plant. If the charge of the acid changes, it’s going to push the nutrient attached off. The free nutrient is going to connect with another charged molecule that may be too large to go through the cell walls.
If you are applying a straight amino acid product to supplement the plant deficiency, think about what else you want to accomplish and adjust the water. If all you are concerned about is getting more aminos in the plant, match the water with the pH of the product.
If you are comparing product A to product B, compare the number of amino acids in the product. The best product is the one that contains all 20 of the amino acids that the plant needs. However, you may find sources of information where the number is slightly lower or higher. Always ask your sales rep how many types of aminos are in the product if they’re not mentioned on the label. If they don’t know, it’s simple, don’t buy the product until they can answer your question.
The approach of covering all these bases when spraying aminos goes against our principle of only apply what the pant needs’. However, because the science has yet to advance to the point in which the exact amount of each amino needed in the plant is known, you’ve got to rely on the manufacturer and scientist who developed the product. Perhaps in time scientists will narrow down some target ranges. However, it will take many years before they zero in and completely understand them due to the instability of the aminos and their rapid movement within the plant.
The most popular mineral acids (MA) used in the turf industry are sulfuric, hydrochloric (muriatic), citric, and proprietary mixtures of a combination of acids. Most Superintendents who use MA are using them to reduce soil pH. Yet, MA’s do much more than reducing pH. In fact, that’s probably the least important thing they do.
Mineral acids are very strong corrosive solutions, with pH’s that can go down to zero. The lower the pH, the stronger the acid, and the strongest acid wins the pH challenge. The strongest guy in the gym wins all the competitions, right? Not if he breaks his leg. Overuse and long-term use of MA can lead to serious problems that may break the soil.
Just as with organic acids, you have to worry about what’s not getting solubilized and where it’s going. We are seeing some serious soil layering and cementation on drainage systems. So, to reiterate; DO NOT OVER APPLY MA! Monitor the soil structure and inspect the gravel layer on the problematic green once a year. Once these problems occur, the solution to them is usually a bulldozer.
MA also free up nutrients for plant uptake, by solubilizing insoluble compounds. That may sound contradictory, if a compound is insoluble how can anything make it soluble? The reality is there is no such thing as an insoluble compound. Every solid on Earth can be converted into a solution if it’s exposed to strong enough acid or heat for a long enough time.
Some MA deposit insoluble compounds into soil macropores, while others solubilize the compound locked up in the air space. Obviously, the MA products that can clean clogged air pores and improve water infiltration are the best products.
Some of the new MA chemistries are starting to show some great promise of eliminating the clogging and layering problem. However, because they are new there is long-term uncertainty.
When comparing products from different distributors, there’s no difference between any if you are comparing the same type of acid. If you want to introduce an MA acid into your program research them all. The wrong choice has the potential to cause serious soil structure problems.
Just like I’ve said above, if you use MA monitor the changes frequently.
PLANT GROWTH HORMONES
We know plant growth hormones (PGH) are used to regulate plant growth but, are they good for plant health? If used correctly, I believe PGH can be beneficial to the plant. However, if overused, they can be detrimental to plant health. If you use PGR, do not go over the label recommendations. PGH isn’t one of those products that if a little is good more will be better. More can cause abnormal growth and mutated cell division.
When it comes to PGH, there are a few things that I am unsure of. I don’t know an affordable way to check PGH balance in the plant. I’m also unsure if anyone knows the perfect balance, because they move so rapidly through the plant. What I do know is that when cutting a grass plant at less than ¼” on a daily basis, it’s going to affect the PGH levels.
When looking for a PGH product as a maintenance product, I suggest looking for one that has a balanced package of the major hormones: Cytokinins, Auxins, Gibberellins. If you are going to use them to fix a temporary challenge, look for the one group of PGH that’s going be most effective to achieve your goal.
Knowing a bit about these hormones can help you select the right product. So, let’s break it down:
- Bending toward a light source (phototropism).
- Downward root growth in response to gravity (geotropism).
- Flower formation.
- Stimulate cell division and elongation of leaf and stem
- Seed Germination
- Promote cell division in plant roots and shoots.
- Enhance cell growth and differentiation
- Affect and leaf senescence.
If you are trying to enhance root growth, supplement auxins and or cytokinin products (mainly in seaweed extracts). If you are trying to move turf laterally or increase the density of the canopy, use a gibberellin product.
All living organisms are carbon-based. Carbon atoms adhere with other atoms which help to structure proteins, fats and carbohydrates, all of which supply other living organisms with nutrition.
Carbon is a nutrient that begins and ends the life cycle of a plant. Plants use carbon dioxide during photosynthesis and convert the energy from the sun into a carbohydrate molecule. Once photosynthesis is completed the life cycle starts. When a plant or plant material die and decompose, carbon dioxide is formed again to return to the atmosphere and start the cycle again.
Practically all sandy or well-drained soils are deficient in carbon because of low levels of organic matter, reduced populations of microbes, clippings removal, and organic matter removal from your aerification practices.
There must be thousands of products that contain carbon, organic acids, sugars, microbial, organic fertilizers, and straight carbon products. When choosing a product remember this: all carbon is good, but not all carbon products are good.
Many carbon products are derived from humalite and/or lenardite. Both are designated as Humate Products, and both are comprised of the same substances: active soluble compounds (Humic and Fulvic Acids), and insoluble ash and heavy metals. Humalite has a much greater percentage humic and fulvic, than lenardite. Lenardite has a greater percentage of ash and heavy metals. Another difference between the two is that humalite is derived from fresh water, while lenardite is derived from saltwater. Naturally, you would want to use the products derived from humalite. However, many of the granular products that were used in the 20th century, were derived from lenardite. Overuse of lenardite products, as proven by our data, leave large deposits of insoluble waste in the soil which causes plugged and layered soil.
There may be some legitimacy behind the minimal use of granular lenardite. However, if you do use it, you should monitor the soil structure closely.
Textbooks say that the ideal target range for the carbon nitrogen ratio is 35-40 to 1. However, on a sand green or other well-drained soil, it’s more realistic to expect 20 to 1. We do a lot of testing for C to N ratio and a large majority of sand-based greens are less than 10 to 1. When soil testing, I recommend your lab test for the C to N ratio, so you can monitor product efficiency, and know when to slow down or stop your applications.
A carbohydrate is a biomolecule containing carbon, hydrogen, and oxygen atoms. Carbs are either simple sugars or complex polymers such as starch and cellulose.
Saccharides sugars are divided into four chemical groups:
Monosaccharides and disaccharides are simple carbohydrates (fructose, glucose, sucrose, and lactose), while oligosaccharides, and polysaccharides are complex (starch, glycogen, cellulose, glucose and glycosidic).
Simple sugars will enhance all organisms in the soil, therefore if you use them, you’ll need to monitor plant disease. If you get a disease outbreak, stop using the sugar product until the disease is eradicated.
Complex sugars consist of several thousands of monosaccharides arranged chains, so keep in mind that fungi can’t break down complex sugars while bacteria can. The advantage of using complex sugars is that you’re only feeding bacteria, and they become much stronger because they have to work hard to consume the food. You can think of this as the health impact different between eating at McDonald’s every meal versus eating healthy food every meal.
Due to the large size of the monosaccharides, a portion of that chain will leach through the rootzone before it is consumed. Sugar waste has the potential to cause strong insoluble compounds (polysaccharides), and layer deep in the soil profile. Therefore, if you’re using complex sugars, monitor soil structure and water infiltration frequently.
There are many sugar products on the market. Some are soil products designed to enhance and build microbial populations. Others are designed as chelates for foliar nutrition uptake, and other products are intended to supplement natural sugars for the plant anatomy. I believe every golf course, farm, or landscape operation should feed the soil sugar to expand and enhance and microbial populations. The levels of beneficial microbes in the soil are strictly dependent on the amount of food in the soil. Feed them and they multiply, starve them and they die.
If trying to decide which science to use, research both methods and determine which concept is best for your situation. The jury is still out for us when using newer straight sugar products. We simply haven’t seen any change in nutrient levels in the plant from our tissue date. However, we don’t test for sugar levels, and I’ve never seen research that shows ideal sugar ranges in turfgrass. That number would fluctuate drastically depending on the height of the cut.
My concern is overuse. Plant and human anatomy are amazingly similar, what happens to humans when they eat too much sugar? They get diabetes. What does too much sugar do to a plant?
This is my theory, and it’s not based only on conjecture: sugars in the plant are formed in the very early stages of the plant life development. Sugar production is heavily influenced by sunlight, photosynthesis and leaf density. Before the first cell of a plant develops, there has to be a sufficient sugar supply to support the growth. Does the plant need more sugar than it’s naturally producing?
In short, we don’t know the answer yet, but we’re working on it. If you use straight sugar and are witnessing a consistently healthier plant, then, by all means, keep using it and let us know what benefits you see. Inputs are the most valuable part of our success.
My knowledge of microbes is fairly strong. I sold one of the original “Bug in a Jug” products in the mid ’90s. Most of the early products had a handful of species that were common to practically every soil in the world. The real secret with the early products was the food being used to increase the native populations. The current day microbial products have hundreds of species of indigenous and non-indigenous species. They are designed to introduce an entire community of organisms that work together to achieve maximum soil health, but do they work? My opinion is absolutely yes, but it may take time to reap the benefits.
Can the theory be proven? Yes, it can, but the expense associated with the testing procedure to identify and count hundreds of species is prohibitive for most golf courses. Because testing is impractical, you have to rely on results and soil data to prove to yourself that the products are viable. Regrettably, it can take a few years before the colony of microbes in the product begin to dominate the population.
It’s world war 3 in the soil every minute of every day. When you add non-indigenous species into an indigenous species they have to fight to survive. In the beginning, they are facing impractical odds of survival. Many organisms live 20 minutes but produce 20,000 offspring in that time. If only 2 organisms endure, you’ve started the community. If you’re in a war and you reinforce the troops every 20 minutes, eventually you’re going to win that war.
My belief is stronger than most because I’ve spent time with microbiologist that develop products and study the task of each species. I’ve also watched root colonization and predator attacks under a microscope. That’s some cool stuff
Many manufacturers make claims on the efficacy of their products, including disease suppression, nematode suppression, nutrient mineralization, improvement in soil texture and structure, and improvement in plant health.
I believe that if you are using a diverse community of microbial organisms, you will eventually experience all those things. Other than visually witnessing the suppression, there is no way to actually prove many of those claims. However, I could frequently prove a reduction in organic matter and improvement in the saturation index after six months.
If you’re a believer in microbial products, the only thing you should be looking at is the number of microbes in the mixture. Very few of the companies are going to show you the names of all the species in the mix because they all have their own secret brew. However, you can trust if a product does have large communities of bacteria that a lot of research went into creating the product.
My belief is that one day every property will have its own unique blend of organisms that are ideal for their property. That won’t happen in my life, but perhaps some of you younger guys will see that theory come true.
I don’t have to give anyone an explanation on oxygen’s impact on life; you’re reminded about 15 times every minute. But, are oxygen products effective? Yes, if you are using the right chemistry.
Can you have too much oxygen in the soil? Perhaps. Think about brand new USGA greens and the challenges of holding water and nutrients in those conditions. I don’t believe you should use oxygen products until the
physical condition of the greens naturally worsens, but I would much rather error on the side of caution when it comes to oxygen.
Unless you’re supplying oxygen mechanically, the only option I know of to get oxygen in the soil is by using hydrogen peroxide (HP). The original HP products work great, but for only about 2 minutes. HP is highly unstable and will volatilize immediately into the atmosphere when sprayed on the surface.
The newer generation of HP product have been chemically enhanced to stabilize them in order to provide a controlled release of oxygen. These products are much more effective than the old HP products and show great promise. The secret of efficiency with the stabilized products is to water them down to the root zone and apply them as frequently as possible.
There are many new technologies used and introduced into the industry. These technologies have created a lot of confusion for superintendents, as it is now difficult to discern which solution is best for their programs.
How do you determine which products fit your challenges? Educate yourself on the science behind the products. Most of the products in each category are either identical or very similar, so buy from the companies you trust the most.
Finally, test the soil and plant tissue to conclude the efficiency of the products, and don’t over-apply just because you can, because overapplying could cause more harm than good.