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lawnlubber
03-27-2005, 03:57 PM
Experts recommend adding x lbs of nitrogen every year to grow a healthy lawn. If you don't remove clippings where does all that nitrogen go? Leachate, run off, unusable nitrogen tied up in the soil where? Why didn't the prairies need fertilizer to grow grass before we came here.

YardPro
03-27-2005, 06:23 PM
it is left in the leaf blades that are cut off.

WhohasHelios?
03-27-2005, 07:31 PM
it is left in the leaf blades that are cut off.

And then begins to break down and become bio-available.

lawnlubber
03-28-2005, 09:32 AM
And then begins to break down and become bio-available.
So if the clippings are not removed there is no need for adding nitrogen every couple of months, true?

marko
03-28-2005, 01:44 PM
So if the clippings are not removed there is no need for adding nitrogen every couple of months, true?

From what I have read/heard, you can supply about 1 lb of N a year from not removing your clippings. It will help reduce the amount you need to put on, but not totally cover it. Not 100% of the nitrogen goes to the leaf blade to be cut off, and recycled. A lot is eventually used or lost to the environment.

WhohasHelios?
03-28-2005, 07:28 PM
From what I have read/heard, you can supply about 1 lb of N a year from not removing your clippings. It will help reduce the amount you need to put on, but not totally cover it. Not 100% of the nitrogen goes to the leaf blade to be cut off, and recycled. A lot is eventually used or lost to the environment.


Exactly..I would not leave it at just the clippings if you want that perfect lawn. While they provide nitrogen over time, if you want perfection, you will have to boost it intermittently as well.

I was not aware that it was aroud 1 pound marko, thats good to know.

-Reuben

dishboy
03-28-2005, 07:37 PM
Exactly..I would not leave it at just the clippings if you want that perfect lawn. While they provide nitrogen over time, if you want perfection, you will have to boost it intermittently as well.

I was not aware that it was aroud 1 pound marko, thats good to know.

-Reuben

According to Turgeon dry clippings contain around 3 % N.

sheshovel
03-28-2005, 09:08 PM
Right but decaying organic matter also burns nitrogen when it's breaking down.

dishboy
03-28-2005, 09:39 PM
Would you consider dry clippings organic matter or organic material?

WhohasHelios?
03-28-2005, 10:12 PM
Personally, I do not consider grass clippings huge consumers of nitrogen while decomposing. The process happens really quickly.

I have noticed this with a lot of mulches however, especially fresh fir and hemlock. The biggish chunks of wood that you think are providing the ground with such great nutrient are actually creating a need for nitrogen.

lawnlubber
03-28-2005, 10:34 PM
When nitrogen is consumed in a lawn it is not annihilated. It is combined with carbon and oxygen and incorporated as living tissue into the organisms in the lawn, but the nitrogen atoms are still present. How specifically are they lost to the environment or are they just not bio-available. How did the Native Americans grow the lush prairie grass of the Midwest without a broadcast spreader.

WhohasHelios?
03-28-2005, 10:45 PM
How did the Native Americans grow the lush prairie grass of the Midwest without a broadcast spreader.


What??

Maybe I need a refresher course on my Native American history....But I did not realize THEY were growing prairie grass...And since when is prairie grass lush and green?

I come from Southern Alberta, the prairies of Canada. There is about two weeks in the spring when things are green and lush.
Every few years, just like alot of forests do, there are fires. These provide alot of needed nutrient to the plants.

Also, plants become accustomed to their envireonments for survival. This means entering summer dormancy for most prairie grasses.

I am not being rude...If I am wrong, please let me know...I just dont think I have ever heard of lush green prairie grass before, and certainly not lush green grass that the natives used to grow...

-Reuben

lawnlubber
03-28-2005, 11:16 PM
I am perhaps giving the Indians too much credit, but we do know that they controlled their environment(largely with fire). I spoke of midwestern prairies, we get a lot more rain than Alberta, enough to grow forest if things are left to nature. When Europeans arrived the Indians were maintaining a tall grass prairie here. The few remnant patches of that, are quite lush (they need to be burned periodically or the forest will take over) until mid summer. When these prairies are burned no extra nitrogen is added, it is simply the nitrogen contained in the plants being recycled. Why isn't it enough when the nitrogen in grass clippings is recycled into the lawn.

WhohasHelios?
03-28-2005, 11:22 PM
Well..My answer to that will go back to my previous one about wanting that PERFECT lawn. Personally, I am a fully chemical free company. I dont feed the grass. I feed the soil. If the soil has all of the fungal and microbial activity it should, then it is usually fine to leave it at just clippings.

But for most people who are not organic, they feed the grass, not the soil...Thereby creating more of a need for a constant supply of N,P,K

That is interesting about the Natives. I was not aware of them maintaining the land as grasses.

But surely these are not the equivalent to our modern day turf grasses..?

-Reuben

lawnlubber
03-28-2005, 11:43 PM
No they didn't grow turf grass and yes that's different I'm just trying to make a point. I believe and observation confirms that feeding the soil as you say works. But I am adding much less than is recommended by recycling grass clippings and topdressing. My lawns should be in decline after 10+ years of being "starved" but they are fine. I am trying to understand why in a scientific not just intuitive way.

WhohasHelios?
03-29-2005, 12:04 AM
No they didn't grow turf grass and yes that's different I'm just trying to make a point. I believe and observation confirms that feeding the soil as you say works. But I am adding much less than is recommended by recycling grass clippings and topdressing. My lawns should be in decline after 10+ years of being "starved" but they are fine. I am trying to understand why in a scientific not just intuitive way.

If you are topdressing and mulch mowing then I doubt the lawns are starved at all. Quite the contrary over the past ten years.

Simply because you are feeding the soil.

The microbial and fungal activity is where it should be. IF you can attain that, you will have success with virtually any type of grass you have there.

Garden Panzer
03-29-2005, 01:17 AM
Most " N " goes into the atmosphere....

timturf
03-29-2005, 03:03 PM
can reduce fertilizer by ~ 30% if you return the clipping!