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JDUtah
08-16-2008, 01:15 AM
So, I know I said I was going to be silent, but maybe a middle ground would be best. :) I will always have questions, and you great folks in this forum are too valuable a resource for me not to ask. So expect questions, but maybe not my long winded opinions on things, at least on this site... :dancing:


The first compost questions...

1- How do you determine moisture % in a compost? (yourself or lab tested with nutrients?)

2- If lab tested, what lab do you use? Is their % by weight, or some other number?

3- If meter tested, what are the meter results telling you- moisture by field capacity? By wieght still??? Or other means????

Thanks

jeffinsgf
08-16-2008, 08:53 AM
Squeeze a handful. If it forms a clump that stays a clump, its pretty wet. If I were paying by the ton, I'd complain and it is sure to give you problems in all but the most sophisticated spreaders. If it forms a clump that holds for a few seconds and then crumbles with even slight pressure, it's kinda wet. I would look cross-eyed at the scale man if I were paying by the ton, and if the word "topdresser" is in the name of your spreader, you should be OK. If it won't form a clump at all, thank God you're paying by the ton instead of the yard and you can spread it with just about anything.


Anything more complicated than that would be a waste of mental energy, in my opinion.

treegal1
08-16-2008, 11:15 AM
hey buddy glad your still around, try a micro wave and a scale, or a fruit dehydrator................

JDUtah
08-16-2008, 12:26 PM
Thanks Tree.

Jeff,
Thanks for the quick field tests. Normally they would apply, but I'm working out a system that will make it esay to control a compost 'fertilizer' application. You need to know moisture % at one point. I'm not going to reveal the process that makes it easy and not a 'waste of mental energy' but I can apply 1 lb of Nitrogen per 1,000 sqft for only $2.50 to $4.00 per 1,000 with a compost that cost $20/yard. + minimal labor.

Moisture % makes the percent by wieght number highly variable, so at one point you need to have an accurate moisture reading. I know I know, I make this organic thing too difficult. :) Lies.

Kiril
08-16-2008, 12:36 PM
http://soils.usda.gov/sqi/assessment/files/chpt4.pdf

JDUtah
08-16-2008, 12:40 PM
Great stuff Kiril. That's exactly what I needed. Thank you.

JDUtah
08-27-2008, 06:41 PM
http://soils.usda.gov/sqi/assessment/files/chpt4.pdf

OK, maybe I am not understanding the title right.. In that article to find soil water content it tells you to...

Soil water content (g/g) = (weight of moist soil - weight of oven dry soil) /
weight of oven dry soil

Is soil water content not percent moisture? If not, how/where do you use that number?

to get the moisture percent wouldn't you do this?

Soil moisture percent = (weight of moist soil - weight of oven dry soil) /
weight of moist soil

And times that by 100?

I'm 99.99999% sure.. but just wanna run it by.

Thanks.

muddstopper
08-27-2008, 07:54 PM
http://multimeterwarehouse.com/woodchecker.htm

ICT Bill
08-27-2008, 08:56 PM
JD, the USDA site has more information than you could shake a stick at, or beat a person over the head with :hammerhead::hammerhead:

For what you are doing they have statistics up the whazoooooooo

JDUtah
08-27-2008, 11:13 PM
ok looks like i'll crawl their site some more tomorrow. Thanks Bill.

Kiril
08-28-2008, 12:58 AM
Is soil water content not percent moisture? If not, how/where do you use that number?

Depends on what your trying to determine.

to get the moisture percent wouldn't you do this?

Soil moisture percent = (weight of moist soil - weight of oven dry soil) /
weight of moist soil

NO! The equation is correct as given (gravimetric water content)

If you want percent water by weight, multiply the result by 100.

percent water by weight = ((weight of moist soil - weight of oven dry soil) / weight of oven dry soil) x 100

What your looking for is volumetric water content.

% water by volume = ((wet soil weight - dry soil weight) / (volume of sample x density of water)) x 100

Kiril
08-28-2008, 01:02 AM
http://multimeterwarehouse.com/woodchecker.htm

Dude, landscapes. :laugh:

http://www.aquaterr.net/soil_probes.htm

JDUtah
08-28-2008, 02:50 AM
Depends on what your trying to determine.



NO! The equation is correct as given (gravimetric water content)

If you want percent water by weight, multiply the result by 100.

percent water by weight = ((weight of moist soil - weight of oven dry soil) / weight of oven dry soil) x 100

What your looking for is volumetric water content.

% water by volume = ((wet soil weight - dry soil weight) / (volume of sample x density of water)) x 100

I am looking for % by weight.

Sorry I left out to multiply by 100.. but I still don't think that's right...?

Example:
Wet soil=10g
dry soil=5g

So with the original equation (where it says divide by dry weight) you get...

((10-5)/5)*100= 100%

When it should be 50% by weight. Right?

But if we do it as ((wet-dry)/wet)*100...

((5-10)/10)*100= 50%

I still think you divide by wet weight? :confused:

JDUtah
08-28-2008, 02:52 AM
Dude, landscapes. :laugh:

http://www.aquaterr.net/soil_probes.htm

What does the percentage of these meters represent? I don't think it can be by weight?

Kiril
08-28-2008, 04:26 AM
http://en.wikipedia.org/wiki/Ratio

jeffinsgf
08-28-2008, 10:27 AM
I am pretty sure JD is right. The formula as printed measures the amount of water in the sample, but then compares it to the other component rather than to the original sample.

Kiril
08-28-2008, 11:33 AM
I am pretty sure JD is right. The formula as printed measures the amount of water in the sample, but then compares it to the other component rather than to the original sample.

The formula is correct.

jeffinsgf
08-28-2008, 12:12 PM
The formula will give you the ratio of water to soil, but not the percentage of the original sample that is water. Using your wiki link, the ratio of apples to oranges is 2:3, but the percentage of the fruit basket that is apples is 40% (2/5).

jeffinsgf
08-28-2008, 12:18 PM
The formula is correct.

You're saying the government has never made a mistake?

:::Thin Ice:::

JDUtah
08-28-2008, 01:53 PM
I'll let you guys duke that out (I had my fix of fightin').. but it is supposed to be divided by the moist(total) weight for percentage...

Came to me last night.. don't know why I didn't realize it before..

For a percentage you take the measure of the part and divide by the whole, then multiply by 100.

The part is water.. so (moist - dry)...

The whole is the wet sample.

So the formula should be wet-dry divided by wet times 100. Run some check numbers through it.. it's the only way to get it to work.

-------

Do you guys know what soil percentages the meters represent??

jeffinsgf
08-28-2008, 02:08 PM
You're right, JD.

On the meter, I'm not certain about this design, but most measure conductivity. Given the highly variable nature of soil structure, I'm not sure how accurate measuring conductivity would be. On the other hand, I don't know how accurate you need to be. ;)

JDUtah
08-28-2008, 02:15 PM
Thanks for the meter input Jeff,

The original question was for % by weight. It's for a compost nutrient application rate calculator. But for field testing soil moisture, conductivity should be good enough? I imagine with time you would learn what the %'s really mean depending on what type of soil you are dealing with?

jeffinsgf
08-28-2008, 02:32 PM
I noticed on the image that it has a sliding scale, for S/L/C, which I am going to assume is Sand/Loam/Clay. I would think that sticking it into a pile of compost would yield highly variable results, depending on your source materials and where your pile is in the decomposition process.

Does your wife know you're going to be baking compost in the microwave? :waving:

JDUtah
08-28-2008, 03:19 PM
I noticed on the image that it has a sliding scale, for S/L/C, which I am going to assume is Sand/Loam/Clay. I would think that sticking it into a pile of compost would yield highly variable results, depending on your source materials and where your pile is in the decomposition process.

Does your wife know you're going to be baking compost in the microwave? :waving:

Haha.. thats on the down low.

Kiril
08-28-2008, 08:23 PM
You're right, JD.

No, your both still wrong. Please try to understand the difference between gravimetric and volumetric water content.

Also please try to understand why you would want take the ratio of water vs. dry soil when comparing weight.

But if you don't believe me, or the posted doc, then perhaps you will believe these sources.

http://www.campbellsci.com/documents/apnotes/soilh20c.pdf

http://www.css.cornell.edu/faculty/hmv1/watrsoil/theta.htm

http://www.oznet.ksu.edu/pr_sme/Soil%20Water%20Content.pdf

http://agbiopubs.sdstate.edu/articles/FS876.pdf

http://ceeldorado.ucdavis.edu/files/45069.pdf

http://www.uic.edu/classes/geol/eaes475/lecture%2013-15%20soil%20water%20notes%20a.pdf


Need I say more?

JDUtah
08-28-2008, 08:55 PM
Kiril, it seems you are trying to tell me what I want.. which sorry to say, you don't.

Volume means squat when you're figuring weight N per 1,000. I know what I need, I know I got it. I hope you had a good day.

JDUtah
08-28-2008, 09:36 PM
Grrr I hate the edit time limits on this forum... I'm a slow poke... :cry: ...to restate my last post...

Kiril, it seems you are trying to tell me what I want.. which, sorry to say, it appears you don't know what I want.

Volume means squat when you're figuring weight NPK per 1,000. But, your persistent evidence does show that the formula is right for gravmatic water content. But it also shows that I am not looking for gravmatic water content. I am simply trying to find out what percent (by weight) of water is in a sample of compost.

If you still think you have what I am looking for, have you been too lazy to run some check numbers with a little common sense? You might want to run check numbers before driving your point next time?

Run the following common sense numbers through the gravmatic water content formula and check answer, then run them through the other formula and check answer.

25% water by weight...
wet=100 g
dry=75 g

50% water by weight...
wet=100 g
dry=50 g

25% water by weight...
wet=100 g
dry=75 g

Gravmatic water content formula... (*100 per your advice)
((wet-dry)/dry)*100=?

Percent moisture (by weight)...
((wet-dry)/dry)*100=?

Seriously, if you think you have what I wanted.. run the numbers and apply a little critical thinking.

Hope you had a good day!

Kiril
08-28-2008, 09:56 PM
If your not looking for gravimetric water content, then don't state the equation that is used to determine gravimetric water content is wrong.

The equations are correct and are used and taught everyday. If you have an issue with the formula, or cannot see why the formula is written the way it is, not my problem. I pointed you to the resource, and several others, do what you want with the information.

JDUtah
08-28-2008, 09:56 PM
oops... one of those 25% should be 75%..
wet=100 g
dry=25 g

Kiril
08-28-2008, 10:00 PM
oops... one of those 25% should be 75%..
wet=100 g
dry=25 g

OK, so what is the density of the water vs the soil, or perhaps you think this is an unimportant consideration?

JDUtah
08-28-2008, 10:07 PM
If your not looking for gravimetric water content, then don't state the equation that is used to determine gravimetric water content is wrong.

You were the one who assumed I was looking for gravmatic water content. You gave me the formula(source)... and lead me to believe it was what I was looking for. I only said that formula was wrong because using it did not give me what I wanted. We now know the formula was not wrong.. but I had the wrong formula.

If you have an issue with the formula, or cannot see why the formula is written the way it is, not my problem. I pointed you to the resource, and several others, do what you want with the information.

I have no issue with the formula. (clearly demonstrated in this post (http://www.lawnsite.com/showpost.php?p=2488449&postcount=27)) And the only problem was that i was temporaily misguided.. but we have it figured out... and things are good now. :walking:

JDUtah
08-28-2008, 10:08 PM
OK, so what is the density of the water vs the soil, or perhaps you think this is an unimportant consideration?

For my application at this moment... yes... it is an unimportant consideration. But at some point I might need it and I thank you for introducing it to me. :dancing:

DeepGreenLawn
08-28-2008, 11:05 PM
you guys are getting extremely technical it seems.

Wouldn't the answer be to take some compost... weigh it... dry it out and weigh it again? Take those to numbers, divide, subtract, whatever you do and there you go...

Or am I wrong once again? I don't know, my brain is fried and I am searching for something to hold my eyes open to get a little more work done before tomorrow.:eek:

JDUtah
08-28-2008, 11:15 PM
Haha, yes that is basically what you do... and the talking is what to subtract/divide/multiply by. :) Have fun getting things done!

jeffinsgf
08-29-2008, 12:44 AM
...percent water by weight = ((weight of moist soil - weight of oven dry soil) / weight of oven dry soil) x 100
...

According to one of your linked PDF's (Cornell's I think) and pure common sense, what you are going to get with that calculation is the ratio of water to soil, which can be expressed as a percentage, but is not the percentage of water by weight, which is what JD asked for. Going back to the wiki apples and oranges, the ratio of 2:3 apples to oranges is 67%, meaning you have 67% as many apples as you have oranges. Whether you express it in percentage terms or a ratio, it is still a ratio and not the percentage of the whole.

Kiril
08-29-2008, 02:15 AM
@Jeff

Original questions by JD.

The first compost questions...

1- How do you determine moisture % in a compost? (yourself or lab tested with nutrients?)

2- If lab tested, what lab do you use? Is their % by weight, or some other number?

3- If meter tested, what are the meter results telling you- moisture by field capacity? By wieght still??? Or other means????

I then post a link to a reference (nothing more), which demonstrated several methods for determining water content.

Which then prompted:

OK, maybe I am not understanding the title right.. In that article to find soil water content it tells you to...

Soil water content (g/g) = (weight of moist soil - weight of oven dry soil) /
weight of oven dry soil

Is soil water content not percent moisture? If not, how/where do you use that number?

to get the moisture percent wouldn't you do this?

Soil moisture percent = (weight of moist soil - weight of oven dry soil) /
weight of moist soil

And times that by 100?

I'm 99.99999% sure.. but just wanna run it by.

Thanks.

What he implied above and in following posts was the equation is wrong. The equation is NOT wrong. What IS wrong is the attempt to use it the way he wants to. You then hop on the train stating the government made a mistake (which they do, but not in this case).

If a lab reports gravimetric water content, then they used the equation in question to determine it. I ask you Jeff, does this not specifically apply to question 2?

@JD and Jeff

What you are looking for, as I stated in my original reply (with an equation), and now again, is volumetric water content (i.e. the amount of water contained within a sample volume). You don't need to know how much the water weighs, that is unless you don't know the weight of a cubic centimeter of water. :hammerhead:

Now I will ask this. What exactly are you doing with this information? Reason being, the intended use of the information will determine which is the appropriate method to use.

JDUtah
08-29-2008, 12:22 PM
Kiril,

I have already stated the use twice in this thread, and I DO NOT want volumetric or gravmetric water content! I wanted percent water by weight.. That's it. If you do not understand the reasoning why, you clearly have never paid attention to how much N, P, or K you have put down when using compost, organic fertilizer, or synthetic fertilizer. Don't you do that for hire? Do you have your applicators license? (the only other explanation that you don't get it would be that you spent way too much time in school which tends to rob a person of critical thinking skills)

Also as you see in my second post (which you just quoted)

Is soil water content not percent moisture? If not, how/where do you use that number?

to get the moisture percent wouldn't you do this?

I clearly came back with an innocent question because the formula wasn't working. I asked if they were different things.

This was your reply....

NO! The equation is correct as given (gravimetric water content)

If you want percent water by weight, multiply the result by 100.

percent water by weight = ((weight of moist soil - weight of oven dry soil) / weight of oven dry soil) x 100

What your looking for is volumetric water content.

% water by volume = ((wet soil weight - dry soil weight) / (volume of sample x density of water)) x 100

Once again, I asked if they were different and you kept pushing that it was the right one which lead me to believe I was still supposed to be using it.

Might I pick out a sentence from that reply. You said, "If you want percent water by weight, multiply the result by 100." I understood this to mean that "percent water by weight" was referring to the whole mass, not percent as it relates to the mass of the soil. And that WAS the confusion, but it's figured out now.

Look, we were both right and neither of us need go on with this argument... the problem was simple miscommunication on both of our parts. Neither of us were clear enough. The end. Say what you need to so you can feel better, but I am done.

Kiril
08-29-2008, 12:29 PM
JD, the formula is the standard way of determining soil water content by mass/weight. I don't give a rats azz how you want to determine it for your purposes (dry or wet weight). The fact of the matter is, in soil science it IS determined using the given formula, and if you expect to use that number in further calculations, then you will have to use that formula.

treegal1
08-29-2008, 12:48 PM
wow the wheel re born, whats all the to-do about any ways. ITS just cr^p??? take a hand full and squeeze it real good and then smell it, I can smell if my pile is to wet or dry.

is the grass going to grow better if it see's the math that this took?????LOL.

jeffinsgf
08-29-2008, 01:37 PM
If the ratio of water to soil is the "standard" measurement, why didn't you say that 3 days ago, instead of implying that neither JD or I know how to figure a simple percentage? In absolutely none of your linked documents do they use the term "percentage of water by weight". You used that term in the following quote, where, I assume, you were paraphrasing the USDA, but their document never uses the phrase "percent of water by weight" -- only your post:

NO! The equation is correct as given (gravimetric water content)

If you want percent water by weight, multiply the result by 100.

percent water by weight = ((weight of moist soil - weight of oven dry soil) / weight of oven dry soil) x 100

The above statement by you is wrong. That will yield the weight of the water as a ratio of the weight of soil, not the percentage of the sample that is water. That may be the academic standard, but it is NOT the percentage of water by weight, as you have said it is.

Like JD, I've wasted more time on this than I care to. A modicum of diplomacy and a half-open mind on your part would have shortened this discourse by a half dozen posts.

treegal1
08-29-2008, 01:42 PM
....................off with there heads................

JDUtah
08-29-2008, 01:45 PM
Tree,

lol, it's not about the pile, it's about knowing what nutrient rates you are putting down in the field. Not everyone has a good lawyer to fight the EPA when they get caught putting down more NPK than the law allows. (a 1/8" compost topdressing in your area in Florida can eat your entire N allotment for the year! 1/4"? Law be broken already.)

Secondly, even if you do have this good lawyer, if you don't know how to calculate (or care to calculate) how much of what you are putting down, it is likely you are contributing to groundwater contamination more than the chemical guys!

Wouldn't that be great, mainstream society switches to the current 'care less' organic practices only to find that their children are born with MORE defects due to INCREASED groundwater contamination?

The chem guys would have a hayday with that!

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

Look guys, I know people think I am on this forum to pursue my own ego. I am not. I want organics to work in our industry. And the only way for us to TRULY get it to work is to establish credibility. The only way to do that is to do things responsibly.

For example: My salts thread is not promoting the use of synthetic fertilizers, it is attempting to correct a myth that discourages their use. If you have a customer where you used that false argument to sell and they find out otherwise, your credibility just went right out the window. And the credibility of the organic maintenance industry as far as that person is concerned.

And this one too... If you tell a customer your practices are safer, and the EPA nails you for irresponsible practices (in this case putting down too much NPK), all your customers quickly realize they were lied to and will probably be tempted to never trust an organic professional again.

Am I re-inventing the wheel? I don't want/mean to. Am I trying to learn how to truly do organics AS A PROFESSIONAL? Yes. Do I believe that is the only way to not hurt this industry? YES!

In that light Kiril, you stated...

JD, the formula is the standard way of determining soil water content by mass/weight. I don't give a rats azz how you want to determine it for your purposes (dry or wet weight). The fact of the matter is, in soil science it IS determined using the given formula, and if you expect to use that number in further calculations, then you will have to use that formula.

Up until you said that, I believed common acceptance of soil moisture was a percent of the whole, not a percent of the soil weight. I haven't grabbed the reasoning why they use that ratio yet, but in the light that it is the standard way of doing things, can you please help me figure out the following...

You have 1/2 yard of compost that you will use to cover 1,000 square feet. The soil test shows the nutrient values by dry weight are 1%-.7%-1%. When you apply the compost the half yard weights 450 lbs. The compost (at time of application) has a gravimetric water content of 45%. How many pounds of NPK did you just put down?

I know how to do it with my % whole, but how would you do it with the gravimetric water content?

treegal1
08-29-2008, 01:49 PM
look at the part that says some thing like " unadulterated naturally produced is exempt". also we have a hard time getting to the 3 lbs mark every year. we are gets lazy

treegal1
08-29-2008, 01:56 PM
and with that logic in mind adding 3-4 feet of dirt to build up a house pad would also be against the law, also a breeze would have a lot of N in it also, how many cf of N in one acre of air??? or lbs?? also one cow turd will give more than 3# of N to the acre per foot???. also is the n tied up with some other things hanging on to the N just waiting to be un locked???

JDUtah
08-29-2008, 02:02 PM
look at the part that says some thing like " unadulterated naturally produced is exempt". also we have a hard time getting to the 3 lbs mark every year. we are gets lazy

No offense Tree, but I read once where you stated your normal topdressing was about .5 yards per 1,000? And you also stated your compost N goal is 2%. And your compost at around half moisture weighed in at 900 lbs per yard... (if any of those numbers are wrong sorry, that is what I remember reading)

That means ONE of your topdressings added 4.5 lbs of N per 1,000! And whether exempt or not.. that N is still leachable.

JDUtah
08-29-2008, 02:04 PM
and with that logic in mind adding 3-4 feet of dirt to build up a house pad would also be against the law, also a breeze would have a lot of N in it also, how many cf of N in one acre of air??? or lbs?? also one cow turd will give more than 3# of N to the acre per foot???. also is the n tied up with some other things hanging on to the N just waiting to be un locked???

Irrational numbers??? And irrational N molecules as represented in the air arguments.

treegal1
08-29-2008, 02:14 PM
and that gets blended down with worm casts and rock dust.
also we have a pile of soil tests that say we need 6 lbs N per acre, again an exemption same with the P. listen the dep / ag office in just next door to the new place, they have there eye on me and will advise me if they dont like my ways. so far its a go ahead and they love me. one guy is even going to get a composter from me as he works at the dep and is in violation of the water shed rules.

sounds like you need a plane ticket.........also as high as 3%maybe 6% some times and that gets to the worms!!!!

JDUtah
08-29-2008, 02:18 PM
and that gets blended down with worm casts and rock dust.
also we have a pile of soil tests that say we need 6 lbs N per acre, again an exemption same with the P. listen the dep / ag office in just next door to the new place, they have there eye on me and will advise me if they dont like my ways. so far its a go ahead and they love me. one guy is even going to get a composter from me as he works at the dep and is in violation of the water shed rules.

sounds like you need a plane ticket.........also as high as 3%maybe 6% some times and that gets to the worms!!!!

So how do you track how much N per topdressing?

treegal1
08-29-2008, 02:19 PM
So how do you track how much N per topdressing?plane ticket, then you can see the dep reports we file.........

JDUtah
08-29-2008, 02:28 PM
plane ticket, then you can see the dep reports we file.........

Winter. :)

treegal1
08-29-2008, 02:29 PM
also WTF, do you thing that the dep really cares about a qp more in per acre, that came out of compost??? they are trying to stop all the un tested fert and squirt guys, and also get the homeowners to stop dumping the bag til its gone. just the fact that we compost animal manure and tree waste to use as a fert, ahem top dress, they really just dont care that much, its a step in the correct direction. most of the farms that are in the (big legal term) co op, are already in violation and have become compliant with the proper compost methods we use. we are the only one in our area that has the forms and a concrete slab or liner under our piles, the only ones that test monthly, I can go on and on. also most of the N is not water soluble the rule is soluble!!!!

JDUtah
08-29-2008, 02:39 PM
The 2% N represented in your tests is not Nitrate? (soluble) What is it? What tests are used?

...Winter...

treegal1
08-29-2008, 02:44 PM
yes, winter............dont let me stop ya, keep going on about the water, it was fun.

JDUtah
08-29-2008, 02:54 PM
Haha, sometimes I feel like all I am doing is making enemies in this forum.

The water...

Well I guess all that is left there is to figure out how to use gravimetric water content to mathematically convert an amount of compost to dry weight so you can calculate NPK.

But I gotta run do some other things before that gets any tinkering...

Smallaxe
08-29-2008, 11:04 PM
....................off with there heads................

I didn't have anyting to add to the discussion - I just wanted to see if that neat Husky chainsaw would help me read page 6. :)

treegal1
08-29-2008, 11:08 PM
hey now that was hard work, out side my self there is few chicks that can hold a saw like that and are picture worthy.

found this one, wow, dont think the mods would want that on here, she had some incredible gear.......

dang it I wish they had an over 18 part to this site.......search girls with chain saws you can not miss her.

Smallaxe
08-29-2008, 11:11 PM
Guess not. But - Oh well. Detail math is fun too. :)

Smallaxe
08-29-2008, 11:14 PM
hey now that was hard work, out side my self there is few chicks that can hold a saw like that and are picture worthy.

found this one, wow, dont think the mods would want that on here, she had some incredible gear.......

dang it I wish they had an over 18 part to this site.......search girls with chain saws you can not miss her.

No matter how many beers I've had - it never occurred to me to do a search of girls with chainsaws. Thanks tg.

treegal1
08-29-2008, 11:23 PM
second row on the right, with the tattoo.......

Kiril
08-30-2008, 01:07 AM
You have 1/2 yard of compost that you will use to cover 1,000 square feet. The soil test shows the nutrient values by dry weight are 1%-.7%-1%. When you apply the compost the half yard weights 450 lbs. The compost (at time of application) has a gravimetric water content of 45%. How many pounds of NPK did you just put down?

I know how to do it with my % whole, but how would you do it with the gravimetric water content?

It is a simple mathematical relationship .... work it out.

@Jeff

None of this B.S. would have even started if you and JD had simply done your homework. I included enough key words in my response for JD or anyone to do the leg work on your favorite search engine. I'm not running a soil science seminar here, and I am not going to do a bunch of leg work to track down web resources for people when they aren't taking the time to do it for themselves, or even attempt to understand the information in the references already posted.

I posted enough links to documents that described the methodology right at the beginning of this silly B.S., it was you and JD who kept dragging it out. Point your finger in some other direction.

phasthound
08-30-2008, 09:42 AM
It is a simple mathematical relationship .... work it out.

@Jeff

None of this B.S. would have even started if you and JD had simply done your homework. I included enough key words in my response for JD or anyone to do the leg work on your favorite search engine. I'm not running a soil science seminar here, and I am not going to do a bunch of leg work to track down web resources for people when they aren't taking the time to do it for themselves, or even attempt to understand the information in the references already posted.

I posted enough links to documents that described the methodology right at the beginning of this silly B.S., it was you and JD who kept dragging it out. Point your finger in some other direction.

I'll have to second that. And add that Kiril has always acted in a civil, respectful manner. There was no need for the silly backlash aimed at him. If you feel the need to make personal statements, please do us a favor and take it private.

growingdeeprootsorganicly
08-30-2008, 04:43 PM
dame jd,

always starting trouble!!! lol

i didn't know nitrate leaching causing birth defects? i thought it was more to do with the synthetics pesticides?
anyway
i think your missing the point about compost and it's n availability and solubility.over thinking it! lawyers for that are the last thing she needs to worry about. she says she tests right? and conforms to their laws
and that post is exempt

i'm not saying depending on the post there might be some leaching"tiny" but there's no way it compares to bagged fert, why do you think it's exempt there, it's not that soluble. and the fact that their sandy soils would benefit from the om in the post helping retain those nutrients even if they are added later in a synthetic form.

i think if every one topdressed with post and cut out the bagged fert all together there would be no issues in fl. with n and p problems, most of the nutrients are locked up thats the beauty of post, plenty of long lasting nutrients,biology and OM. remember what kiril says!

JDUtah
09-03-2008, 09:13 PM
dame jd,

always starting trouble!!! lol

i didn't know nitrate leaching causing birth defects? i thought it was more to do with the synthetics pesticides?
anyway
i think your missing the point about compost and it's n availability and solubility.over thinking it! lawyers for that are the last thing she needs to worry about. she says she tests right? and conforms to their laws
and that post is exempt

i'm not saying depending on the post there might be some leaching"tiny" but there's no way it compares to bagged fert, why do you think it's exempt there, it's not that soluble. and the fact that their sandy soils would benefit from the om in the post helping retain those nutrients even if they are added later in a synthetic form.

i think if every one topdressed with post and cut out the bagged fert all together there would be no issues in fl. with n and p problems, most of the nutrients are locked up thats the beauty of post, plenty of long lasting nutrients,biology and OM. remember what kiril says!

http://pubs.usgs.gov/fs/2008/3063/

http://www.cdc.gov/mmwr/preview/mmwrhtml/00042839.htm

http://www.cbdmp.org/pdf/nitrates.pdf

http://www.reopure.com/nitratinfo.html

Now compost does have (or cause) less nitrate per lb than synthetic ferts, but my concern is in the 1/8" to 1/4" topdressing practices. Then you are (well can be) putting down more Nitrate than a synthetic fert.

Now to figure out how to use gravimetric water content to get what I want...

treegal1
09-03-2008, 09:54 PM
the septic tanks all taken out and all the millions of lbs of chem fert off the market and we would no issue with the n from natural sources or animal manure. and the N is more stable on top of the ground in the root zone here at least, its sort of like a sand filter, the good stuff/ or bad stuff( i guess it all depends on where you sit or stand) just leaches into the top 12-15 inches and hangs out there for a while, especially compost!, the problem starts to manifest when it rains and the granules from badged fert wash off the top and into the water ways, the compost and ct is IMO usually set into the soil and root system better just with the volume and the application methods. eh any ways, the law types love what I do and I just got to play along and do what i can............

treegal1
09-03-2008, 09:59 PM
also you still did not re analyze the mix, casts= 1/3 more or less, and have no n to tell about, the rock dust is all minerals, and locked up, the compost at 6% N if it ever got that high is only 1/3 of the total volume? its almost like the PH ghost again.

JDUtah
09-03-2008, 10:00 PM
Yeah Tree, I wasn't continuing our little spiff, I dropped that. I will be out this winter (to learn, not argue). :) I was simply following up with Deeproots question "i didn't know nitrate leaching causing birth defects? i thought it was more to do with the synthetics pesticides?"..

Looks like not necessarily birth defects, but infant fatality.

I am tempted go on with the other, but wont. Hope your day is going well. :)

JDUtah
09-03-2008, 10:02 PM
also you still did not re analyze the mix, casts= 1/3 more or less, and have no n to tell about, the rock dust is all minerals, and locked up, the compost at 6% N if it ever got that high is only 1/3 of the total volume? its almost like the PH ghost again.

PM me the percent by weight of each.. I'll throw you a number back. :) Or I can throw another excel calulator together for you...

I know you don't believe it matters (like pH) but I believe it does (like pH).

DeepGreenLawn
09-03-2008, 10:15 PM
maybe by the time you get down here you can make a pit stop on your way back home and check out my future operation. If I can get it up and running by then...

JDUtah
09-03-2008, 11:36 PM
maybe by the time you get down here you can make a pit stop on your way back home and check out my future operation. If I can get it up and running by then...

That would be delightful. :)