Is this fertilizer burn?

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Sapling

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I was wondering what else this may be besides fertilizer burn ....
The tree in question is approximately 5 to 7 years old and it was fertilized last may/june with a 21-7-7 via liquid injection. Within a matter of a few weeks the trees leaves went from green, to orange then red to brown. This year it looks as though it is dead. There are no leaves coming out.
Is this a cut and dry case of fertilizer burn or could it be something else? There are several other trees in the yard which also received the same fertilizer application and they look great.
Any advise or suggestions as to what else this could be would be greatly appreciated.
 
sounds likely

You really haven't given much information to work with. Are all the trees the same variety? Got any pics during any of the stages? When applied?

I suspect that the application was done by a commercial applicator, rather than yourself. I personally don't ever sell soil injections, because I think there are better ways. IMO, all it does is make nice green spots in the lawn where the application was done, and it makes some customers feel good about doing good for their trees.

If you did this yourself, what was the concentration of the fert solution, and how much was applied to each tree and at what distance from the trunk. You never specified the chemical nature of the fertilizer, there are many different aspects to each fertilizer component. The "21-7-7" number is almost useless without knowing the actual components involved. A strong mixture of a salty fertilizer solution can easily kill a tree. Bigger trees are better able to survive a poorly made application than the little ones.

At this point, it is probably too late to make an accurate assessment of the cause. You might take it up with the people that did the fertilization, but I would expect them to deny any claims. If you did it, you might want to consider a different method of treatment in the future.

Any future tree fertilization: take a soil sample, then follow the recommendations (if they are specific for the "crop" that you listed). Just broadcast the fertilizer on the ground around the tree, then the lawn and the tree will benefit without any hideous green (or dead) spots.
 
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No pictures, all trees in yard are different. This particular tree has cedar bark chips around the base. I am sure it has just gotten too much nitrogen but I wanted to find out if there were any other possibilities based on the leaf discolouration.

Can I ask why you prefer to do a broadcast application vs a liquid injection? Is this with a granular form of fertilizer?
How do you treat this type of application if there are obstacles such as landscape rock and mulch on the ground surface under the tree(s)? :dizzy:
 
Can I ask why you prefer to do a broadcast application vs a liquid injection? Is this with a granular form of fertilizer?
How do you treat this type of application if there are obstacles such as landscape rock and mulch on the ground surface under the tree(s)?

My trees started looking better after I realized that what I needed to do was feed the microbes in the soil, not pump chemicals into the trees root zone. Millions of microbes, fungi, bacteria, and any other organisims feed on the organic material you broadcast over the area. Think of it as quicksand slowed down ever so many times. If there is mulch on the surface you are already feeding said microbes to a certain degree. I agree that the injection is perhaps what is killing the tree.
 
My trees started looking better after I realized that what I needed to do was feed the microbes in the soil, not pump chemicals into the trees root zone. Millions of microbes, fungi, bacteria, and any other organisims feed on the organic material you broadcast over the area. Think of it as quicksand slowed down ever so many times. If there is mulch on the surface you are already feeding said microbes to a certain degree. I agree that the injection is perhaps what is killing the tree.

I also think it is the fertilizer but now I am wondering more about granular applications.

I guess I need a little clarification on all of this....
What are you using? What is its makeup?
I am assuming this is different than "fertilizer" i.e. the 21-7-7 that was used.
If I wanted to look into this some more what could you tell me about it/where to look for more information, etc.
I was looking into organic fertilizers (also via liquid injection)...any opinions on these?
 
Unless the concentrate was liquid based and thay really messed up on the mixing instructions it would be very difficult to "burn a tree". If all the trees died than yes but only one died and the other are fine I would look for other answers as to the trees demise.
 
I use cornmeal and small alfalfa pellets. Broadcast over the lawn and in the trees root zone; they break down fairly quickly. Buy them at the feed store.
 
Unless the concentrate was liquid based and thay really messed up on the mixing instructions it would be very difficult to "burn a tree". If all the trees died than yes but only one died and the other are fine I would look for other answers as to the trees demise.

Nonsense !

If one tree had too much applied in the root zone, then burn, baby, burn! (salt burns, that is). There are some liquid fertilizers that have a relatively low salt index, others are downright dangerous to plants. If one tree was already stressed, then a severe overapplication was made, it's done for. Particularly if the mixture was too concentrated.

You need to understand the the N-P-K numbers you quoted represent the final analysis of Nitrogen, Phosphorus, and Potassium applied. They do NOT represent how salty or "HOT" the fertilizer is.

Since you have not commented on what product was used, I don't know if it contained Potassium chloride, or Potassium Sulfate. Ammonium phosphate is commonly used in soluble mixtures to get the phosphorus component, but without reading the label, everything is just guesswork. Urea is a pretty safe source of nitrogen, but not nearly as good as urea formaldehyde or methyl urea. Ammonium nitrate would be very hot, but it is also the most efficiently utilized nitrogen source available, which is why the farmers use it.

Regarding granular or liquid: the important difference is not the amount of water included with the application, but whether it is put straight into the soil surrounding the roots. When a granular application is made to the surface several good things happen: 1. it won't get likely into the root zone in a toxic dose unless watered in fairly well. This almost prevents toxic doses by dilution with water. 2. It is a more tangible method of measuring how much fertilizer is applied. 3. Labor is almost neglible, risk is reduced, results are better. Why use any other method?

Some people are fond of drilling holes into the ground and then pouring the fertilizer into the hole. Works well, but it often kills small areas in the turf, and is very labor intensive.
 
I found a product label for this stuff, but it does not list the ingredients. It's probably only available in canada; I think US formulations must list the ingredients.

http://www.growercentral.com/index....ls&familyID=260730&CFID=5878331&CFTOKEN=12339

This is an acidic fertilizer, and carries a pretty strong label for that purpose. It's label even indicates that it is well suited for acidifying irrigation water, but it includes the warning to run clear water for 10 minutes to wash the fertilizer off the foliage. It does not mention any use for soil injection on trees, and the concentrations that it suggests using are too dilute to provide lasting benefit to trees, unless you did it once every two weeks, as suggested.

I suspect that product could really be a problem for some plants. It lists 16% potassium nitrate in the MSDS, and that is a really "salty" product, although it would be readily available to the plant. It also calls for a pretty low applied concentration, and is clearly not safe to use if improperly diluted. Quote:
[To fertilize with 100 ppm Nitrogen, add 48g Plant-
Prod® 21-7-7 to 100 L of water; for 200 ppm Nitrogen,
add 95 g to 100 L of water.] For an english conversion at the stronger concentration, that is 3.35 oz (about two shot glasses of product) in 27 1/2 gallons of water.

Most soluble tree fertilizers I have used call for one 20 lb bag per 100 gallons of water: MUCH stronger and probably made up of chemicals that are not quite so "hot". If you mixed this stuff up that strong, I would suspect that was your problem. When I mix up a liquid lawn fertilizer application, I routinely add 350lbs of urea, 100 lbs of urea formaldehyde, and 50-100 lbs of potassium sulfate per 500 gallons of water. I have not found a soluble source of phosphorus that is safe and economical. This mixture is a little bit salty, but not so strong that it will cause foliage burns unless applied in the summer heat. The product you used does not sound safe at those application rates.

Next time you do some fertilizing, read the label very carefully to see that the products are not as harsh to the plants.

For the most part, any chemicals used to fertilize plants that have words in them like ammonium- , -chloride, -nitrate are pretty salty. Use lower doses for greater safety. The acidity of any chemical is quite a bit more complex, and you should just read the label carefully.

Organic compounds like urea must be decomposed by bacteria (or others) in order to be taken up by the plant. The organic compounds are much safer, and less likely to cause pH problems or salt burns. When I say "organic", I am refering to "organic chemistry" which has ABSOLUTELY NOTHING to do with "organic farming". It's just one branch of chemistry that usually involves itself with complex carbon compounds, rather than "inorganic" compounds like potassium nitrate.
 
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Again if someone used a liquid fertilizer and screwed up the mixing yes it's possible.
Maybe just maybe something else was going on.
 
Again if someone used a liquid fertilizer and screwed up the mixing yes it's possible.
Maybe just maybe something else was going on.

I agree completely.

I was only attempting to address the probability of the problem being caused by a fertilizer burn. I think there was a good chance of that.
 
Sounds like something besides the fertilizer that killed the tree. Maybe some borers attacked the tree and killed it or a disease. The fertilizer was applied in May of 2007 and was the tree green and growing last year ? I have fertilized thousands of trees and never have burned one with salt or nitrogren. pdpql I have to disagree with you on fertilizing trees and when I am done this fall with our apps I will let you know how it went and how much it added it to our bottom line.
 
Once we removed the tree it was pretty evident that the tree has girdled itself. I really didn't think it was the fert but at the time couldn't explain it. I did soil tests, etc to check the area and it didn't look as though the tree was in a good spot all around, in addition to the girdling.
 
I would like to caution you all on not taking PDGDL's information seriously. (Excellent info, PDQ.)

Yes, girdling roots are a serious problem; however, I could start posting pictures of mature, 80-year-old trees with girdling roots that are still alive and kicking.

It is almost never ONE thing that kills a tree but an accumulation of stressors. Girdling roots do cause constriction. Overfertilization can also cause issues that may have had a hand in the "last straw" for this tree.

Pointing the finger at one thing and ignoring another is limiting your overview to the complex nature of tree care.

Sylvia
 
Yes your right about girdling roots in old trees as we have Live Oaks here on the coast that are 200 yrs old and they have girdling roots. When it comes to over fertilizing I have never over fertilized a tree due to the tree only taking up the amount of material it needs to grow and flourish. I only deal with slow release fertilizer and we have all sand in our soils here on the island.
 
If all of the trees received the same treatment, but only one of them browned out and died, I'd have to say it was NOT the treatment, regardless of the product used. They would all have been affected.

As far as what's a good organic or natural product to use?
Granular:
Sustane 4-6-4 works well for me, as does Plant Health Care Tree Starter or 3-4-3 Healthy Start. Both of these are myco rhizal inocculated.

Liquid:
I like Bolster liquid, or Plant health Care Bio Pak or Tree Saver. Also always had good luck with compost tea. Best part of compost tea is the price: almost free!! Take some compost, pit it in some cheese cloth, stick it in a 5 gallon bucket of water and run a fish tank bubbler through it for 8 hours or so. Gotta be used right away, but, as long as you started with good compist, it's an awesome fertilizer for any plant.
 
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