INSTRUCTIONS
COMPOST CALCULATOR
Gary L. Bertrand
Professor Emeritus Chemistry
Missouri University of Science and Technology  -  MS&T
REFERENCES

    
Type of Calculation

Input Data


Calculate C/N & Moisture %

from Known Amount
Component 1:

Select Below


Amounts in:  Gal     Lbs


Amount of Component 1 






Calculate Amt of Component 2
Needed for Desired C/N

Component 2:

Select Below



Amount of Component 2 





Calculate Amt of Component 2
Needed for Desired Moisture

    

C/N Ratio: 

 Moisture:
 








                                                 

comp
1

Material:
comp
2

%N
w/w
C/N
w/w
Moist
w%
Density
lb/gal
Newspaper
0.1
650
5
0.25
Cardboard (Corrugated)
0.1
560
8
0.5
Sawdust
0.2
440
39
2
Straw
0.7
80
12
1
Leaf Mold
0.4
60
40
3
Leaves (shredded) Loose, Dry
0.9
54
38
1
Leaves (shredded) Compact 0.9
54
38
2
Manure, Horse
1.6
30
72
6.8
Coffee Grounds
2
20
80
7
Manure, Cattle
2.4
19
81
7.2
Grass Clippings, Loose
4
17
82
1.7
Grass Clippings, Compacted
4
17
82
3.2
Table Waste
2.4
15
70
3.5
Poultry Bedding
2.7
14
37
4.3
Garden Waste
3.2
12
65
3
Manure, Chicken
8
6
69
7.3
Mixture




New    




New    







































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COMPOST CALCULATOR
INSTRUCTIONS


This program is designed to estimate the amounts (weight in pounds or volume in gallons) of different components in a composting mixture to achieve a desired C/N Ratio and/or % Moisture.  The weight calculation requires estimated properties of the components: PN (percentage Nitrogen based on Dry Weight), C/N (Carbon to Nitrogen Ratio w/w), and Percentage Moisture in the component as it is mixed.  The densities (pounds/gallon) of the bulk components are needed for mixing by volume, which is usually more convenient for home composting. 

A table of these properties for some common materials is provided.  There is a provision for two other ("New") materials to be added, as well as a combination ("Mixture") of two components.  This added information is not stored by the computer, and is lost on re-starting or Refreshing the Web Page.

Calculating C/N and Moisture % from Known Amounts:
    1. Click the button to select this option.    This automatically puts "5" in the blank
        beside "component 1", clears the amount of component 2, and shows that these
        quantities will be calculated.
    2. Select the desired materials as "Component 1" and "Component 2".
    3 Edit the blank beside "component1" if a different amount is wanted, and enter a value
       for "component 2".
    4. Make sure that the desired units ("Gal" or "Lbs") is selected and click on "Calculate".
    5. The  calculated values appear.
    6. If you want to add another component, click on "Save Mixture".  The calculated values
        for  the mixture appear in the table of properties.  The mixture can then be selected as a
         component for further mixing. 
    7.  Repeat step 6 to add more materials.
Adding New Materials:
    1.  To add new materials, you must have estimates of the of the Percentage Moisture,
        Percentage Nitrogen,  C/N Ratio, and possibly the Bulk Density of the material.  A
        large collection of such values is at :
                                On-Farm Composting Handbook - eXtension Online Campus https://campus.extension.org/.../NRAES%20FarmCompost%20manual%201992.pdf
pp 106-115
    2.  Enter appropriate values in Line 10 or 11 and click on "Save New Data".
    3.  These added materials may be replaced by replacing the data and clicking on
         "Save New Data".
Calculate the Amount of Component 2 Needed for Desired C/N Ratio or Moisture %:
    1. These calculate the amount of component 2 to be mixed with a specified amount of
         component 1 to achieve a specific value of either C/N Ratio or Moisture %.
    2.  Click on the desired Type of Calculation.  Enter appropriate values for the amount of
         component 2 and the desired outcome in the blank spaces.  Click on "Calculate" and
         the required amount of component 2 will appear in the upper "calculate" space, and the
         corresponding result will appear in the lower "calculate" space.



































REFERENCES

THE SCIENCE OF COMPOSTING     http://cwmi.css.cornell.edu/chapter1.pdf

HOT COMPOSTComposting in 18 Days         https://deepgreenpermaculture.com/diy-instructions/hot-compost-composting-in-18-days/

C/N Ratio
by Tom Richard and Nancy Trautmann        http://compost.css.cornell.edu/calc/cn_ratio.html

Carbon-to-Nitrogen Ratio         https://www.planetnatural.com/composting-101/making/c-n-ratio/

Moisture Content by Nancy Trautmann and Tom Richard    http://compost.css.cornell.edu/calc/moisture_content.html

HOW TO USE COMPOST ACTIVATORS        http://www.homecompostingmadeeasy.com/compostactivator.html


NPK VALUE OF EVERYTHING - Searchable Database   https://www.thenutrientcompany.com/npk-value-of-everything-organic-searchable-database/

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