Tree Fertilizer

[YooHawn]

Is fertilizing a tree really useful? I have an oak which was struck by lightning sometime ago, but is healing fine. Two tree experts (certified arborists) have suggested fertilizer in the process of providing estimates for trimming my other trees.

 

[John Paul Sanborn]

What is in the "fert" and what do they want to do?

IMO straight NPK fert is not beneficial for mature trees.

i find the thought of boosting 3 elements and saying that we should allow the plant to get the rest from the soil is absurd.

I prefer products with broad spectrum of elelments such as seaweed and fish emultion products. cured manure and sewage sludge are a distant second, and then muched leaves and such.

We do not reallyunderstand the realtion ship between trace elements and compounds and plant health, which is why I prefer the seaweed.

High rates of N will force fast succulent growth, that lacks the compounds that inhibit pest propbelms. Not a good thing.

Mulching and periodic deep watering are the 2 best things we can do for a tree. The downward movement of water is the primary force in soil gas exchange. Short duration surface irrigation, such as most of us use for lawns, will only promote shallow rooting in trees.

 

[Kneejerk Bombas]

IMO straight NPK fert is not beneficial for mature trees.

NPK fertilizer is benificial to trees or other plants if it's lacking in the existing soil. Plants all have a range of nutrient levels where they thrive, if the soil chemistry is off, why not fix it.
A simple soil test will tell.

i find the thought of boosting 3 elements and saying that we should allow the plant to get the rest from the soil is absurd.

NPK is used in comparitively large quantites by plants and are often lacking in soils, the same things cannot be said about trace elements. In fact, boosting trace elements, possibly to a toxic level, without a soil test indicating their absence, is absurd.

I prefer products with broad spectrum of elelments such as seaweed and fish emultion products. cured manure and sewage sludge are a distant second, and then muched leaves and such.

We do not reallyunderstand the realtion ship between trace elements and compounds and plant health, which is why I prefer the seaweed.

We don't understand them, so add them?

High rates of N will force fast succulent growth, that lacks the compounds that inhibit pest propbelms. Not a good thing.

Yet nurseries do this exact thing.
In some cases it is perfered to to force fast growth and just deal with the side effects. Could increasing growth rates to add wood to an injured tree be one of those cases?

Mulching and periodic deep watering are the 2 best things we can do for a tree. The downward movement of water is the primary force in soil gas exchange. Short duration surface irrigation, such as most of us use for lawns, will only promote shallow rooting in trees.

Isn't watering a tree the same thing as fertilizing it with high N?
What happens to the huge tree with lush foliage, from regular watering, once the watering stops?

------------

YooHawn,

You will find three are differing opinions on fertilizing. It is a high profit part of tree work so it is often sold. If the fertilizing is not based on a soil test, I would opt not to have it done. Unless the if the arborist has done many soil tests in your area, and they all had similar results.
Current thinking is not to add more than about 1 lb of Nitrogen per 1000 sq. ft. At this low level you should not run into the problems JPS mentioned.
I do agree with JPS about removing lawn under the trees and anding compost and/or woodchips, only if it can be done without pesticides, without disturbing the soil at all, if the total depth of the ammendments is less than 3 or 4 inches, and those ammendments do not touch the tree's trunk. Otherwise, leave the grass.
I also think stressed trees should be watered during times of drought. So if the lighting damaged trees go a week or two without rain in the heat of the summer, go give them a good soaking.

 

[Dan F]

Originally posted by Mike Maas

High rates of N will force fast succulent growth, that lacks the compounds that inhibit pest propbelms. Not a good thing.

Yet nurseries do this exact thing.
In some cases it is perfered to to force fast growth and just deal with the side effects. Could increasing growth rates to add wood to an injured tree be one of those cases?
[/B]

Just because nurseries do it doesn't make it right! I suppose you will also say that planting a tree with the root flare 6-8 inches below grade is right because the nurseries do it that way?

Nurseries are concerned with production, plain and simple. The faster they can grow a tree, dig it, and then sell it, the more money they can make. If they can plant a whip and turn around and sell it as a 3 inch tree in 5 years instead of 6 years, they have saved themselves a fair amount of money. I can't blame them for wanting to turn over their stock quickly, it's understandable.

YooHawn:
Like Mike said, you will get three different opinions from three different people. Here's your third.

From everything I've been taught, have read, and understand, if you take care of the root system, the part of the tree that you see will take care of itself.

I agree with Mike; have a soil test done to determine whether you are lacking any certain elements.

I also agree with JPS; you probably don't want a high NPK fertilizer, at least on the nitrogen side.

I will agree with both of them on the watering. And if you can remove the turf. I personally, though, don't see a problem with killing the turf with a chemical such as Round-up. The discussion on Round-up has been raging the last few days on another thread, but Round-up should not adversely affect your tree. There's probably airborne things adversely affecting your tree more now than Round-up killing the grass ever will.

I'm somewhat surprised that JPS didn't suggest a registered consulting arborist. Have one come and look at the tree. He (or she) can make a much better determination after they look at the tree than we all can here. I'm sure JPS can provide the link on how to find one.


Dan

 

[ORclimber]

Mike, do you do your soil testing in house, or send it to a lab???

 

[Kneejerk Bombas]

We do soil pH tests ourselves, but send soil fertility samples to the local university extention office. They are cheap, fast and efficient.
Having a third party do the testing eliminates a possible conflict of interest, or the appearence of one.

Originally posted by Dan F

Nurseries are concerned with production, plain and simple. The faster they can grow a tree, dig it, and then sell it, the more money they can make. If they can plant a whip and turn around and sell it as a 3 inch tree in 5 years instead of 6 years, they have saved themselves a fair amount of money. I can't blame them for wanting to turn over their stock quickly, it's understandable.
Dan

Dan, is there evedence that having a fast growth rate in a young tree is bad? Can you think of a reason, even without research, that inducing a tree into a fast growth pattern at some point in it's life might be bad?
Think about the size of growth rings in relation to a tree's growth rate. Couldn't accelerating a tree's growth rate help to speed the repair of a trunk injury?
If I have a small tree in my yard and I want it big, can't I give it ideal growing conditions and lots of nitrogen to make it big fast? Then after it reaches a size where it's doing some good, slow the growth rate down. Are you telling me this tree will be worse off for the fast growth of it's youth, and a similar tree without the nitrogen will do better in the long run?

You don't even want to get me started on damage to mature trees from pesticides dumped on their roots(including roundup).

 

[Treeman14]

Yoohawn, rather than listen to us squabble about this and that, perhaps you would care to peruse some credible data compiled by the University of Florida. I know several of the people who contributed to this research and have the highest respect for them. Here is the link: http://edis.ifas.ufl.edu/EP114

 

[Bob Wulkowicz]

Originally posted by Treeman14
Yoohawn, rather than listen to us squabble about this and that, perhaps you would care to peruse some credible data compiled by the University of Florida. I know several of the people who contributed to this research and have the highest respect for them. Here is the link: http://edis.ifas.ufl.edu/EP114

I saved it and bookmarked for a later perusal, but in the first reading, there didn't seem to be much marrow in the bones--but then again, I'm obstinently picky. No disrespect intended; they seem just the same factoids in a new blender.

And speaking previously of bones, how about if I throw this one out for the crowd to sniff at:

I believe the rational internal modulators of growth rates for trees, as you are discussing, are the time it takes for cambium cells to mature to a psysiological point where they can divide again. Think about it.

Division is not an instantaneous process. Cells will divide; grow and mature; and, at the point <u>they</u> are readt; they divide again. What essentially gives a tree its girth is the continued accumulation of the number of xylem cells in the diameter.

If a cambial cell divides, say every 3 days, in its process of growing up as xylem, are we saying that nitrogen somehow speeds up that physiological maturition? There are many states and conditions to get lined up inside a cell in anticipation of dividing anew. Is nitrogen the magic bullet that fluffs that preparation away as unnecessary?




I've said for years that wound closure is governed more by the mathematics followed by cells, than by externals like dressings. I really don't care to wage any battle over this turgid myth, and I think people ought to still experiment with dressings, compounds and conditions, rather than continue an extended sandbox pettiness of who said what, whenever.


This business (ala the Florida site) is still preoccupied with buying fertilizers from chemical companies. (I don't think I saw the word organic in there once.)

God, how did trees survive before Dow came along? (Oh, oh .Maybe Dow is God spelled sideways, so I should be careful...)



Anyway, Tubs signing off for a nap, another unavoidable 3 letter part of my life now.


Bob Wulkowicz



PS: Oops, I've said it again that trees run on tree time. I'm sorry, I justy can'y get that simple rule out of my noggin...

 

[John Paul Sanborn]

Mike throughs in another red herring; I say mature trees, he brings up nursey stock .

This is my thought prosess; We remove all the leaves and bead branches form the landscape, and plant turf. Often all the topsoil is removed also, then a small layer is added to appease the new owner.

Trees are suposed to then grow in this.

By applying a seaweed "emultion" I am in effect using a green manure that is more available to the plant.

By definition organic products will have some N in them, by applying high rates we stimulate suculant growth. Recent studies have shown that this practice increases cell size, not cell number .

rather than listen to us squabble about this and that, perhaps you would care to peruse some credible data compiled

So, Brett, I guess I am incredible

Seriously, though, my beleifs are based on nascent science and imperical data, as well as my anectodal observations.

Regularly fertilized (as in NPK application ) trees have more insect and disease problems.

 

[underwor]

I may as well put in my two bits. After 35 years in business, I do not know of a single tree I have seen that was deficient in N to the point of affecting "normal" growth. I am sure that most trees that I have seen could have been souped up with a little N, but was it needed. Your prize Yugo could have been souped up too, but would the rest of the system have held up under the increased power and speed? At a recent seminar, a soil scientist gave the results of a study of how much N is recycled in a normal forest environment, where we usually do not need to fertilize to keep trees growing "normally", whatever that is. His study showed that the rate was between .16 and .17 lbs per 1000 square feet per year. This is considerably less than we have seen suggested to apply over the past 30 years.

I am a fan of poking the holes for aeration, but fill them with compost or thatch from the lawn to solve that problem. If nature had intended all trees to grow fast, she would have only made poplars and willows. Oaks are supposed to be slow and steady. So grab a cool drink, set back in the shade and chill out at the speed of nature. If you are in a hurry for shade, get a Tree of Heaven and you will be in your own little heaven, or hell, in a few years.

Bob Underwood

 

[SilverBlue]

You are all wrong!

 

[TREETX]

Originally posted by SilverBlue
You are all wrong!

What wit, how can I argue with that??

Hint, break the pills in half

 

[Kneejerk Bombas]

Originally posted by John Paul Sanborn
Mike throughs in another red herring; I say mature trees, he brings up nursey stock .

JP, you are always soooo critical of my comments. So, I carefully took a line by line approach to rebutting <i>your</I> comments. Not once did you mention Mature trees, and I only mentioned nursury trees to show that there could be times when high nitrogen is a good thing. The nursury tree reference was only a very small part of my response.
At least you carefully ingnored all the direct questions and critiqued my writing style.

 

[Kneejerk Bombas]

Originally posted by Bob Wulkowicz
Division is not an instantaneous process. Cells will divide; grow and mature; and, at the point <u>they</u> are readt; they divide again. What essentially gives a tree its girth is the continued accumulation of the number of xylem cells in the diameter.

If a cambial cell divides, say every 3 days, in its process of growing up as xylem, are we saying that nitrogen somehow speeds up that physiological maturition? There are many states and conditions to get lined up inside a cell in anticipation of dividing anew. Is nitrogen the magic bullet that fluffs that preparation away as unnecessary?




PS: Oops, I've said it again that trees run on tree time. I'm sorry, I justy can'y get that simple rule out of my noggin...

It does speed up division and cause cells to grow bigger. I don't know about magic bullets.
As far as how mature they are, you are asking the wrong guy, hehe.

 

[Kneejerk Bombas]

Originally posted by underwor
I am sure that most trees that I have seen could have been souped up with a little N, but was it needed.
Bob Underwood

Finally, someone agrees with me.


On a case by case baisis, in only certain situations, could nitrogen be used as a tool a to help the tree?

 

[SilverBlue]

Originally posted by TREETX
What wit, how can I argue with that??

Hint, break the pills in half

And by the way… trees manufacture their own food –thanks anyways. Minerals, oxygen, carbon, and more are utilized to build and maintain structure, day-to-day functions, disease control etc etc.Not to mention the most important role of soil life.

Actually “feeding” a tree or any plant for that matter is a totally backwards approach developed by the chemical industry for use of soluble nutrients which does more harm long term than good. In the real world, trees and other plants are only a part of the complex network of living organisms etc, many which form a symbiotic relationship, yet all are connected somehow utilizing minerals in both soluble and complex form.

In order to understand how trees are only part of the complex “soil food web” one needs to understand how nature actually works and how trees fit within the overall picture.

This brings up the subject of organic and synthetic methodology developed by man-too complex a subject to discuss on one thread.

JP does have the best approach to restock soil supply,

And here is some ‘food for thought’

Thunderstorms are an important source of nitrogen, and trees can regulate its uptake as well as other various minerals. How you ask?

Carbon is typically overlooked - as is oxygen, any why do we haul away leaves in the fall?

How do microbes break down NPK, other minerals into the form that trees can use?

Next time you have the chance, take a walk in a forest and observe nature at work. Investigate the forest floor and note how nature recycles and while you can’t observe most of the billions of microbes and other soil life, there’s plenty of info available on the web.

 

[TREETX]

Actually “feeding” a tree or any plant for that matter is a totally backwards approach

Ok, it is giving them what they need to make food. If you are peeved by the personification given to tree processes, lets jump on healing, wounding, breathing,etc, and ....feeding as well.

Many people think of fertilizers as plant food. A more accurate analogy would be to think of them as plant vitamins. Fertilizers are typically a combination of inorganic elements like nitrogen, phosphorous, iron or copper. Trees need these minerals to "manufacture" essential complex molecules like proteins, starches and structural tissues. Ideally fertilizers are applied to soils to supplement minerals that may be in short supply or that are present in a form that cannot be absorbed by the tree.

Read and take this test, we all need a better understanding here. Test is at the bottom. http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookPS.html
We all need to be working from more than the basic 6H2O + 6CO2 --> C6H12O6+ 6O2

Thunderstorms are an important source of nitrogen

Haven't got a solid grasp on photosynthesis, so we are throwing the nitrogen cycle into the mix

They actually prduce N??? Wow, that is simply amazing. I thought it was nitrogen fixing - the enormous energy of lightning breaks nitrogen molecules and enables their atoms to combine with oxygen in the air forming nitrogen oxides. These dissolve in rain, forming nitrates, that are carried to the earth. Atmospheric nitrogen fixation probably contributes some 5-8% of the total nitrogen fixed.

Breaking apart diatomic N is very difficult. Fixed N is a different story, you can break it with heat alone. Not so difficult - I have done this before, 1050-1100 Celcius is optimal temp(yep, that IS hot..total combustion). From there, you can combine this newly separated N, in a highly excited state, with O3, which produces a chemiluminescent effect giving off light. Measure this amount of light, and you have the total amount of fixed N in a compound without interference of diatomic N. Sorry about the tangent.

Back to trees. In general, I feel that if the soil on a site can't support a tree, other options should be explored mainly, 044. I seek long term solutions with the guiding philosophy that trees should be a legacy for future generations and not a liability for one's retirement nest egg. I do fert when doing other things to modify site so it is more hospitable to tree life. For example, in conjunction with mulching or a form of vert mulching.

 

[Bob Wulkowicz]

Originally posted by John Paul Sanborn
......

Seriously, though, my beleifs are based on nascent science and imperical data, as well as my anectodal observations.

And here I thought they were based on absent science, imperial data, and observations often in need of an antidote...


Bob Wulkowicz

 

[John Paul Sanborn]

Originally posted by Mike Maas
Not once did you mention Mature trees, and I only mentioned nursury trees to show that there could be times when high nitrogen is a good thing.

Hmmmmm, here is the a cut from my origional post. IMO straight NPK fert is not beneficial for mature trees.

Sorry to disapoint you in your atempt at true discourse, but I was tired and we have the discussion at least on a quadrenial basis.

And i just thought I'd slap you with your own stick. I don't usualy employ sarcasm, I prefer irony.

 

[John Paul Sanborn]

Trees need these minerals to "manufacture" essential complex molecules like proteins, starches and structural tissues.

Darn, you put it in quotaitons, so I cannot make a snide comment that thees ont have hands.

Sorry about the tangent.

Those are the tangents I like, along with the cool links. I have not studied some of that since high school. (1980 seems just like yesterday, don't it Bobbalu)

I get annoyed by the parsing wars too. Vigor/vitality, Trim/ Prune.. Though i do sorta lean away from wound healing.



I seek long term solutions with the guiding philosophy that trees should be a legacy for future generations and not a liability for one's retirement nest egg.

Another good thing about organics, is that the home owner can aply them without damamging the lawn. Mix the fish guts in a bucket and pour into most soil.