3 Tree Fertilization Techniques_article

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Would this make sense to your average homeowner?

  • Yes, it makes total sense.

    Votes: 4 40.0%
  • Some parts are a little confusing

    Votes: 3 30.0%
  • No, it makes no sense

    Votes: 3 30.0%

  • Total voters
    10
  • Poll closed .
I cut my teeth coming up through Bartlett Tree so naturally this is the type of fertilization I was accustomed to. It's too much $$ for some companies to let go of. We all grow and learn new aspects of our industry. If not you become stagnant and do more harm than good.

Many fertilizer regimens push top growth at the expense of root development (the bags of macros sold by sponsor's of this site) making plants vulnerable to stressful environments. Frequent, high levels of fertilizer can produce an unbalanced and often unsustainable shoot-to-root ratio. The P disrupts the alliance between the fine root hairs and Mycorrhizae. Mycorrhizae on the other hand, feed plants and stimulate root growth.

Your method has its place but by and large it would be better to research a more sustainable fertilization practice for your clients trees. :)

I always test the soil before I fertilize, and don't regularly fertilize any of my clients, I prefer a more holistic approach with regards to the care of trees.

I frequently see burn on the leaves of the trees I look after within in the confines of my employment because the ground has dried out after a liquid application. so 'when' I fertilize I use timed release sachets from a supplier that isn't a sponsor of this site. I would however be more likely to encourage my client not to clean up all the leaf matter from beneath there in autumn in order to let natural decomposition promote a healthy rhizosphere.

I have also used mycorrhizae stimulants although I do know the jury is still out on whether they work or not, for my part I seemed to have good results as far as plant vigor goes.

My work really lies in connecting people and services toward the restoration of woodland, and it's natural understudy.This is taking up more and more of my time. I never have nor ever will be a 'chemical pusher' however I'm aware of their value when treating certain 'individual' specimens.

I have a great deal of respect for the company that you used to work for as they have pushed things forward in so many ways, however we have been using their services for weeks on end for the last few months, and some of their work has been decidedly 'lack luster' .
 
I have also used mycorrhizae stimulants although I do know the jury is still out on whether they work or not, for my part I seemed to have good results as far as plant vigor goes.

Do mycor inoculations "take"? Data can be found supporting both positions. We can say with a fair amount of certainty, though, that the practice of dumping a big bag of macros into the tank and topping the slurry off with a bag of mycor for soil injection is a waste of product.

Tree fertilization is big business. Perhaps the big "B" leads the way.

I have a great deal of respect for the company that you used to work for as they have pushed things forward in so many ways, however we have been using their services for weeks on end for the last few months, and some of their work has been decidedly 'lack luster' .

Most of my experience was with the lab in Charlotte, NC. You would be hard pressed to find a more knowledgeable, hardworking bunch. The individual offices dotting the world, well...

so 'when' I fertilize I use timed release sachets from a supplier that isn't a sponsor of this site.

TTK, little more about about this product, please.
 
Do mycor inoculations "take"? Data can be found supporting both positions. We can say with a fair amount of certainty, though, that the practice of dumping a big bag of macros into the tank and topping the slurry off with a bag of mycor for soil injection is a waste of product.

Tree fertilization is big business. Perhaps the big "B" leads the way.



Most of my experience was with the lab in Charlotte, NC. You would be hard pressed to find a more knowledgeable, hardworking bunch. The individual offices dotting the world, well...



TTK, little more about about this product, please.

You'll notice that I complimented your company with regards to 'pushing things forward', that was obviously directly complimenting the research side of the company. My dissatisfaction was with the work carried out during the last several months by some tree crews (no I don't care to mention who they are that is inappropriate).

I have the utmost respect for the laboratories and research, and I'm very proud of the fact there is one in my home country in Reading.

The product I have used is Nutri Pak but I will not be entering into an internet debacle on the viability of the product as I also feel this in appropriate.

I totally agree with you when you say the Big 'B' leads the way.

Thanks Weasel. Have a nice day.
 
Not looking for an internet debacle. Just lookin for more info.

You have a nice day, as well.
 
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To accurately fertilize, each site should be soil tested. Even better would be tissue analysis to see that the plant/tree is taking up what is available. You would then tailor the fertilizer rate to the site, as long as all the nutrients needed were available in the mix. One thing interesting I picked up at a workshop this past fall is that trees in the urban environment are often manganese deficient, while trees in the woods can experience Mn toxicity. Also due to cost and environmental concerns, phosphorus has been eliminated from many lawn fertilizers. Trees draw P from the soil which eventually leads to turf decline and greater P runoff from the landscape (from increased soil erosion). The moral I guess is that trees in the landscape are unique and do require addition of nutrients because leaves are removed. How much, you don't know without soil sampling and tissue testing. The best way to fertilize would probably be by adding back compost to the root zone. You would need to add a lot because compost is low analysis, on the order of 1-1-1 or .5-.5-.5. That would most mimic nature and possibly avoid pushing tree growth with fertilizer.
 
To accurately fertilize, each site should be soil tested. Even better would be tissue analysis to see that the plant/tree is taking up what is available. You would then tailor the fertilizer rate to the site, as long as all the nutrients needed were available in the mix. One thing interesting I picked up at a workshop this past fall is that trees in the urban environment are often manganese deficient, while trees in the woods can experience Mn toxicity. Also due to cost and environmental concerns, phosphorus has been eliminated from many lawn fertilizers. Trees draw P from the soil which eventually leads to turf decline and greater P runoff from the landscape (from increased soil erosion). The moral I guess is that trees in the landscape are unique and do require addition of nutrients because leaves are removed. How much, you don't know without soil sampling and tissue testing. The best way to fertilize would probably be by adding back compost to the root zone. You would need to add a lot because compost is low analysis, on the order of 1-1-1 or .5-.5-.5. That would most mimic nature and possibly avoid pushing tree growth with fertilizer.
rep fer that,good info. i like good ol low analysis dry roots organic food with micorrhizae
 
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I read this and believe it as an interesting start.

Pqdl and Treeco. Could I encourgae either or both of you to suggest a basic regimen for tree fertilization that less experienced arborists like myself could use or recommend??

I have discussed this concept on other forums and the stumbling block is usually soil testing. Accurate soils testing costs money the avaerage HO is unwilling to spend where I work. Have you alternatives ....?

I would be happy to recommend a basic regimen. Unfortunately, I don't believe that one exists. I personally don't recommend tree fertilization unless there is a demonstrated need, which is rather uncommon in our area. About all I ever see that calls for "fertilization" is iron chlorosis for pin oaks, which is really a soil condition problem.

There are too many soil types, too many widely different tree varieties, too many environmental conditions to believe that there should be a "basic regimen". To even pursue that goal suggests that the operator is seeking a sales & marketing solution, rather than a tree care regimen.

I occasionally get calls from customers seeking tree fertilization as part of their property maintenance program. I ask them why they wish to fertilize the trees, and they typically respond with a vague answer indicating that they just want to do what is best for them. They are invariably fertilizing the lawn beneath the tree anyway (usually over-fertilizing!), and I assure them that the tree is getting more of that fertilizer than the lawns are.

I believe in throwing fertilizer on the ground and letting the grass and trees fight for it. Typically, you need more fertilizer under the trees just to get the grass to grow there. So far, no one has ever convinced me that the trees don't get more of the fertilizer than the grass.

I have recommended tree fertilization in heavy clay soils, along with deep aeration methods, when tree plantings are not prospering. Usually it is a case of root-bound transplanted trees, not insufficient fertility.
 
By the way, soil testing really doesn't cost much. The home owner can invariably take their dirt to the local county extension agent, and get a decent test.

Don't even think about buying those stupid "test it yourself" kits. I know too much about analytical and quantitative chemistry to think that I could do it myself, and I know that someone with less knowledge than myself would only be fooling themselves. The key to reliable results in soil testing is LOTS of training, a complete laboratory, and standarization, followed by lots of tests, and then chased with more standardization.

I send mine to A & L Laboratories. A bit more expensive than the county extension agent, but much faster response, and you get a better report. If you have questions, you can call them and speak to an agronomist.

http://www.al-labs.com/
 
By the way, soil testing really doesn't cost much. The home owner can invariably take their dirt to the local county extension agent, and get a decent test.

Don't even think about buying those stupid "test it yourself" kits. I know too much about analytical and quantitative chemistry to think that I could do it myself, and I know that someone with less knowledge than myself would only be fooling themselves. The key to reliable results in soil testing is LOTS of training, a complete laboratory, and standarization, followed by lots of tests, and then chased with more standardization.

I send mine to A & L Laboratories. A bit more expensive than the county extension agent, but much faster response, and you get a better report. If you have questions, you can call them and speak to an agronomist.

http://www.al-labs.com/


Thanks for the help mate. I should have said it from the start but I live and work in Perth, Western Australia so local recommendations for products or services are probably not going to help.

The local soil is sandy, low in nutrition, repels water readily and has large quantities of limestone close to the surface. When pH testing for turf maintenance it was regularly 7.5 and even 8.5 in some locations. I have never done a "soil analysis" so I cannot offer any information there but it is interesting that you do not suggest self testing kits. I take your point about the skill and equipment required to get an accurate result.

Sounds like I need to have done with it and track down a cost effective soil analysis service. In the mean time is mulching the base of the tree as wide as the canopy, (or as wide as the HO will permit), a wetting agent and extra water the right start?
 
In the mean time is mulching the base of the tree as wide as the canopy, (or as wide as the HO will permit), a wetting agent and extra water the right start?

Of everything mentioned so far, there is nothing you can do that will be more beneficial for a tree than proper mulching.

Dave
 
I believe in throwing fertilizer on the ground and letting the grass and trees fight for it. Typically, you need more fertilizer under the trees just to get the grass to grow there. So far, no one has ever convinced me that the trees don't get more of the fertilizer than the grass.

You're spot on here. Throwing fertilizer on the ground does indeed feed everything and the trees will draw the nutrients stronger than the turf will. Chances are if there is a lawn fertility program, the trees don't need anymore.
As to testing, labs around here typically charge 20 to 30 dollars per sample. OSU extension no longer does soil analysis. They do have a list of labs serving the Ohio area. One thing to consider is that you need to have a lab that is familiar with the soils in your area and their inherent characteristics. There is a lab in Columbus, OH that specializes in landscape (turf and hort) soil sampling and they work nationwide. They also do tissue tests. Most farm co ops (i.e. Sunrise or Town and Country) can provide sampling too.
 
Let the trees and grass fight for it? Years ago I tackled a big project while my son was still at home to help. It involved tearing out a large culvert, regrading to let a swale do its work, 100 ton of fill, and moving a bunch of dirt. A year or 2 later, my wife called my attention to a very dramatic line in the grass, much greener on one side than the other. Now I had stirred the dirt around every which way, including swapping some of the clay the builder left with muck from bog I buried. Please don't tell the EPA about me destroying a wetland. It even had willows growing there when we moved here. After some study, I concluded the green grass was on the far side of where I chopped off all the tree roots ripping out the culvert.
 
The greener grass could be caused by fungus decomposing the dead wood debris or other organic material in the soil. Typically the green patches are formed in circles and are known as fairy rings. As the fungal colony grows outward the living part is always at the outside and you see dark green grass because the fungus is breaking down organic matter and releasing nutrients. I have seen it in lawns before, it does tend to be more predominant with willows though. I've seen it happen a lot when willows are removed. It is indicative of a fertility problem in the rest of the lawn. In other words, it looks more green because the rest of the lawn is actually more yellow. In reference to my above post, I was saying that the trees will receive nutrients that are surface applied and will tend to pull it away from the turf. I know on tree farms the fertilizer is usually broadcast. Some tree growers don't even use fert unless it's needed and then only in the first one to two years. The advantage to injection is that you get the chemical below the grass for the most part so the tree is not competing. I don't know whether it's beneficial or not to fertilize trees in the landscape. I know there are downsides to fertilizing but I don't know of any studies that have actually quantified a benefit concerning landscape trees; I will say that it kept me working though.
 
That's good! Nutri Pak 16-8-8 i just got a sachet from the garage.

Nutri-Pak seems to be a conventional fertilizer inside a "special" plastic bag with small holes allowing the fert to be slowly released.

Futhermore they make these claims on the product website:

"Q. Does the pH level in the soil effect the nutrients coming out of the packet, thereby making them unavailable to the plants for uptake?
A. No, because the moisture going into the packet goes in as a vapor leaving behind the acidity or alkalinity in the water that the pH has effected thereby making the moisture entering the packet pH neutral."

Q. Can I use a root stimulator or Mycorrhizal type product with Nutri-Pak®?
A. Yes, it is recommended to use those types of products with Nutri-Pak®, as it will only enhance Nutri-Pak’s performance.

Q. If Nutri-Pak® last three years, does that mean I can only sell it to my customers every three years?
A. No, because as the tree or shrub grows it will need more packets installed to achieve optimum growth levels, so your customer can add a packet or two each year, installed at the drip line evenly spaced and 6-8 inches deep.

Q. How safe is Nutri-Pak® for the environment?
A. Nutri-Pak® is SAFER for the environment than other fertilizers for the following reasons:

Due to the Nutri-Pak® Micro-Pore packaging, the fertilizer is contained and will not wash away, thus preventing contamination of groundwater supplies, unlike other fertilizers.
Nutri-Pak® is proven to increase the growth rate of trees or shrubs by up to 125%, resulting in an accelerated conversion of carbon dioxide into much needed oxygen. Here's how:

Carbon dioxide conversion takes place during the growth of the tree or shrub.
A tree or shrub not fertilized spends the majority of its energy seeking nutrients and has much less energy to convert carbon dioxide.
A tree or shrub that is fertilized with Nutri-Pak® spends the majority of its energy converting carbon dioxide into oxygen and much less energy seeking nutrients.
Nutri-Pak® is inserted 6 to 8 inches into the soil. Therefore it is not a threat to people or animals. Other fertilizers that are applied topically and could potentially harm people or animals.
The polyethylene packet does eventually leave the soil, as it is consumed by the acids and micro-organisms in the soil. Unlike other plastics found in landfills that take hundreds or thousands of years to break down, the Nutri-Pak® packet is totally consumed after several years."

http://www.nutripak.com/faq.html

I believe keeping anabolic metabolism slightly greater than catabolic metabolism should be your goal. Doing that without disturbing important relationships between the tree roots and the soil is paramount. Mulch is probably the best way to go in most cases. :dunno:
 
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[edited for brevity]

... The advantage to injection is that you get the chemical below the grass for the most part so the tree is not competing. ....

Nonsense.

Buffalo grass roots up to 19 feet deep. Bluegrass, Fescue, and Bermuda grass grows to 6' deep.

I dug up some 10 day old fescue once. The seedlings were 1"-3" tall, the roots were already 18"-24" deep!! I'll admit, however, that the growing conditions were ideal

How long is YOUR fertilizer injector ? Do you REALLY think that you are putting the fertilizer where the grass can't get it?

Think about this too: research shows that the vast majority of tree roots are in the top 12" of the soil. So explain again to me why are you deep injecting the fertilizer? My guess is because the homeowner doesn't have the equipment to do the injections, and that makes it an easier service to sell.
 
The greener grass could be caused by fungus decomposing the dead wood debris or other organic material in the soil. Typically the green patches are formed in circles and are known as fairy rings. As the fungal colony grows outward the living part is always at the outside and you see dark green grass because the fungus is breaking down organic matter and releasing nutrients. I have seen it in lawns before, it does tend to be more predominant with willows though. I've seen it happen a lot when willows are removed. It is indicative of a fertility problem in the rest of the lawn. In other words, it looks more green because the rest of the lawn is actually more yellow. In reference to my above post, I was saying that the trees will receive nutrients that are surface applied and will tend to pull it away from the turf. I know on tree farms the fertilizer is usually broadcast. Some tree growers don't even use fert unless it's needed and then only in the first one to two years. The advantage to injection is that you get the chemical below the grass for the most part so the tree is not competing. I don't know whether it's beneficial or not to fertilize trees in the landscape. I know there are downsides to fertilizing but I don't know of any studies that have actually quantified a benefit concerning landscape trees; I will say that it kept me working though.

No, it was a straight line right down where the old culvert had been. The grass between the culvert and house was much greener than the grass between the culvert and trees.
 
More nonsense!

Woodweasel: they are selling you lies and other misinformation. Their products are probably good fertilizers, but they should tell the marketing department to spend a little more time understanding their product.

Nutri-Pak seems to be a conventional fertilizer inside a "special" plastic bag with small holes allowing the fert to be slowly released.

...

Well, that could certainly be true. But is the released fertilizer "special" in some way, or is it just a fancy way to sell more cheap nitrogen as "slow release"?

Answer: Yes! The MSDS for Nutri-Pak 16-8-8 reveals that it consists of "A Mixture of Ammonium Sulfate [(NH4)2SO4], Diammonium Phosphate [(NH4)HPO4], Muriate of Potash [KCL] and Urea, packaged in a controlled-release packet."

Let me assure you that these are all cheap, soluble, mineral fertilizers, except for the urea, which is not exactly known as a slow release fertilizer. Keeping these chemicals in a slow release bag is probably a good idea, since they are ALL instantly water soluble. That fertilizer blend is so salty, you could use that stuff to melt the snow off your sidewalks. If buried in little holes without their special bags, you would probably see little death zones in the lawn around each deposit, about 1 week after the first rain.


"Q. Does the pH level in the soil effect the nutrients coming out of the packet, thereby making them unavailable to the plants for uptake?
A. No, because the moisture going into the packet goes in as a vapor leaving behind the acidity or alkalinity in the water that the pH has effected thereby making the moisture entering the packet pH neutral."

This is a clever deception!

"pH" is a logarithmic scale that relates the concentration of H+ (acid) atoms. An H+ atom is smaller BY FAR than any fertilizer atom, smaller even than the water atom that they claim can pass through their special packet. There is NO barrier in existence that can pass water and NOT pass H+ and OH- ions. If the water can get into their packets, so can the "pH" ions. So their statement is utter nonsense.

Since their fertilizer ingredients are "all mineral" ionic compounds, they are all instantly available for uptake by the plants (except the urea), once they diffuse out of the packet. Under nearly all soil conditions, the phosphate ions will react quickly with soil elements to become insoluble, and that reaction IS pH dependent. The ammonium ions are also highly reactive, but plant roots are pretty good at sucking that stuff up. Muriate of potash is exactly what you buy when you go to the grocery store and buy imitation table salt. So far as I am aware, NOTHING can keep that from being "available to the plant"


Q. If Nutri-Pak® last three years, does that mean I can only sell it to my customers every three years?
A. No, because as the tree or shrub grows it will need more packets installed to achieve optimum growth levels, so your customer can add a packet or two each year, installed at the drip line evenly spaced and 6-8 inches deep.

Well sure. The more you fertilize, the more you buy. The more you buy, the happier their company will be. But then again, do they mean "optimum growth levels", or do they really mean "maximum growth possible with excessive fertilization" ?

Q. How safe is Nutri-Pak® for the environment?
A. Nutri-Pak® is SAFER for the environment than other fertilizers for the following reasons:

Due to the Nutri-Pak® Micro-Pore packaging, the fertilizer is contained and will not wash away, thus preventing contamination of groundwater supplies, unlike other fertilizers.

Preventing? No. Reducing contamination by making it a slower release: true. Better yet, if you are worried about groundwater contamination: fertilize with organic materials only, and get ZERO groundwater contamination.

Nutri-Pak® is proven to increase the growth rate of trees or shrubs by up to 125%, resulting in an accelerated conversion of carbon dioxide into much needed oxygen. Here's how:

Much needed oxygen? Since when? Oxygen is typically considered a byproduct of atmospheric carbon capture. Plants manufacture themselves out of sunlight, minerals, and "thin air".

Carbon dioxide conversion takes place during the growth of the tree or shrub.
A tree or shrub not fertilized spends the majority of its energy seeking nutrients and has much less energy to convert carbon dioxide.
A tree or shrub that is fertilized with Nutri-Pak® spends the majority of its energy converting carbon dioxide into oxygen and much less energy seeking nutrients.

Plants don't use much energy "seeking nutrients". They do invest a considerable amount of energy in root development, which is highly desireable. If a plant is grown in an over-fertilized medium, it will have insufficient root development. This predisposes the plants to increased rates of failure in times of stress. Poor soil fertility obviously is to be avoided for obvious reasons.


Nutri-Pak® is inserted 6 to 8 inches into the soil. Therefore it is not a threat to people or animals. Other fertilizers that are applied topically and could potentially harm people or animals.
The polyethylene packet does eventually leave the soil, as it is consumed by the acids and micro-organisms in the soil. Unlike other plastics found in landfills that take hundreds or thousands of years to break down, the Nutri-Pak® packet is totally consumed after several years."

That sounds nice, but even paper is predicted to last nearly forever in the anaerobic conditions of a landfill. 20 year old hotdogs have been found that looked as good as the day they were buried.

I am not familiar with the Nutri-Pak product, but it doesn't sound like the best way to fertilize. It sounds overpriced and labor intensive to apply. I believe that any "spot" application of a fertilizer will incline a plant to develop better roots only in the vicinity of the higher concentrations of what it needs. Spot fertilization also has a MUCH greater probability of doing localized damage with excessively high fertilizer concentrations.

Better: improve the soil fertility across the entire root zone, and have a healthier, more disease and stress resistant plant.
 
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