SZNS 03 7:2014 
 
ICS 65.0 20          Edition 1              
 
 
 
 
 
 
ESWATINI NATIONAL STANDARD  
 
 
 
Organic fertilizer – Specification  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Published by: Eswatini Standards Authority  
Marble Construction Building, Plot 247  11th Street King Mswati II I Avenue West  
P. O. Box 1399, Matsapha, Kingdom of Eswatini  
Telephone: +268 2518 4633, Facsimile: +268 2518 4526  
Website: www.swasa.co.sz  
E-mail: info@swasa.co.sz   
©Eswatini Standards Authority 201 4 
 
SZNS  037:2014 
Edition 1  
 
 
ii            ©SWASA 2014 – All rights reserved  
          
  
COPYRIGHT NOTICE  
 
This Eswatini Standards Authority (SWASA) document is a Eswatini National  Standard and is 
copyright -protected by SWASA. Neither this SWASA document  nor any extract from it may be 
reproduced, stored in a retrieval  system or transmitted in any form or by any means, electronic, 
photocopying, recording or otherwise, without prior written permission being secured.  
 
Requests for permission to reproduce should be addressed to : 
 
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Eswatini Standards Authority  
P.O. Box 1399, Matsapha  
Tel. + 268 2518 4633  
Fax: + 268 2518 4526  
E-mail: info@swasa.co.sz   
Website: www.swasa.co.sz  
 
Reproduction may be subject to royalty payments or a licensing agreement.  
Violators may be prosecuted.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 SZNS 037:201 4 
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©SWASA 2014– All rights reserved                iii
               Table of changes  
 
Clause Changed  Date  Change  
 
Clause  3.5 2012  Insert a space between the N 2 and fixation. Delete 
the word concentration and nutrient in the 
definition.  
 
Clause  3.8 2012  Delete the word ...of...and replace with ...to. 
Change the word crops and replace with plants.  
 
Clause  3.9 2012  Remove the amounts that are given in the 
definition. Add the examples of macronutrients.  
Clause  3.10 2012  Do not give the amoun t of nutrients. Delete cobalt 
in the list of micronutrients as it has not been 
identified as a plant nutrient, replace it with nickel  
 
 
Clause 5.4  2012  Change ‘test for’ and replace with ‘levels of’ to 
read as:’  Levels of pathogens for organic fertiliser’  
Clause 5.5  2012  Change the ‘level’ to ‘levels’ so as to read 
‘allowable levels f heavy metals in organic 
fertiliser’  
Clause 5.7  2012  Change ‘ alumum ’ to ‘aluminium’.  
 
Clause 8.1  2012  The word ‘ suitable’  is a subjective word. Members 
argued that the word  has been quantified by the 
phrase ‘ afford maximum protection from normal 
hazard of transportation and handling’.  
Clause 9.1.3  2012  Delete this clause because colour bands are not 
compulsory, manufacturers will decide on whether 
they include this or not.  
 
Clause 9.2.5  2012  Replace the FPA registration number with 
harmonized system classification number . 
 
 
NATIONAL FOREWORD  
This Eswatini National  Standard was prepared by Technical Committee SWASA/TC 22 Soil 
conditioners and fertilizers in accordance with  procedures of the Eswatini Standards Authority, in 
compliance with Annex 3 of the WTO/TBT Agreement. During the preparation of this National 
standard , assistance was derived from the Philippine National Standard, PNS/BAFPS 40:2008 
Organic fertilizer . 
 
 
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 Contents                     Page   
1 Scope ................................ ................................ ................................ ................................ ....................  1 
2 Normative references  ................................ ................................ ................................ ...........................  1 
3 Definitions  ................................ ................................ ................................ ................................ ...........  1 
4 Classifica tions  ................................ ................................ ................................ ................................ ...... 2 
5 Requirements  ................................ ................................ ................................ ................................ ....... 3 
6 Sampling ................................ ................................ ................................ ................................ .............  4 
7 Test Methods ................................ ................................ ................................ ................................ ...... 5 
8 Packaging ................................ ................................ ................................ ................................ ...........  5 
9 Marking and lab elling  ................................ ................................ ................................ ..........................  5 
Annex A  Determination of total water (Thermal Oven Method)  ................................ ...........................  7 
Annex B  Determination of carbon and organic matter (Walkley - black method)  ................................ . 8 
Annex C  Germination test  ................................ ................................ ................................ ......................  9 
Annex D  Determination of total nitrogen  ................................ ................................ .............................  12 
Bibliography  ................................ ................................ ................................ ................................ ........  14 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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 Organic fertilizer  – Specification  
1 Scope  
This standard applies to organic fertilizer  in its primary (humus) form.  
2 Normative references  
The following referenced documents are indispensable for the application of this document. For dated 
references, only edition cited applies. For undated references, the latest edition of the referenced 
document inc luding any amendments applies. Information on currently valid national and 
international standards can be obtained from the Eswatini Standards Authority (SWASA).  
ISO 23560 Woven polypropylene sacks for bulk packaging of foodstuffs  
ISO 7406 Fertilizers – Marking – Presentation and declarations  
ISO 8358 Solid fertilizers – Preparation of samples for chemical and physical analysis   
SZNS 011 Compound fertiliser – Specification  
3 Definitions  
For the purposes of this standard, the following definitio ns shall apply:  
3.1  
bio-organic fertilizer  
an organic fertilizer material of fully decomposed product of plant or animal origin which is fortified 
with beneficial microbes and enzymes to eliminate pathogens, render inert foreign impurities such as 
pharmac euticals and antibiotics, and improve the availability of the material’s macro and 
micronutrient contents for faster absorption by the plant  
3.2 
compost  
any product of plant or animal origin that has undergone substantial decomposition through natural 
processes or accelerated with the use of microbial inoculants and/or proper C:N ratio of substrates 
where traces of the original materials are still recognizable, maybe partly soil -like in texture, and can 
supply nutrients to plants  
3.3 
fortified organic ferti lizer  
pure organic fertilizer enriched with microbial inoculants, hormones, chemical additives, or inorganic 
fertilizers to increase their nutrient content or further enhance material decomposition  
3.4 
humus  
that stable fraction of organic matter after a m ajor portion of plant and animal residues have  
decomposed, usually amorphous and dark in colour  
3.5 
microbial inoculants  
biologically active products containing optimum population of one or a combination of active strains 
of beneficial bacteria, actinomyc etes, enzymes, algae and fungi that are useful in different biological SZNS  037:201 4 
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  activities, such as N2 fixation,  accelerated decomposition of organic residues and  solubilization of a 
specific element from the soil for faster absorption by the plant  
3.6 
organic fer tilizer  
any product of plant or animal origin that has undergone substantial decomposition either through 
natural or accelerated processes through the application of microbial inoculants where the original 
materials are no longer recognizable, free from an y pathogens, soil -like in texture, contains not less 
than 20 % organic matter (o.m.), and can supply nutrients to plants  
3.7 
organic matter  
any material that originates from living organisms  
3.8 
pathogens  
organisms causing diseases  to man, animals and  plants 
3.9 
plant macronutrients  
group of nutrients needed by plants in large amounts  
NOTE These include; calcium, magnesium, nitrogen, potassium, phosphorus, and sulphur.  
3.10 
plant micronutrients  
group of nutrients, which are essential for plant growth but  are required in small amounts  
 
NOTE These include readily available forms of iron, manganese, boron, molybdenu m, copper, zinc, chlorine, 
and nickel.  
3.11 
pure organic fertilizer  
an organic fertilizer material or any substantially decomposed product of pla nt or animal origin which 
was not enriched with chemical ingredients to increase its nutrient content with minimum total NPK 
of 1.5 %  
3.12 
treated animal manure (TAM)  
bio-organic fertilizer made from pure animal manure treated with microbial inoculants to kill 
pathogenic bacteria and render inert pharmaceuticals and antibiotics ingested by the fowl, through a 
hastened fermentation and decomposition process and enriched with beneficial microbes and enzymes 
to help release the manure’s full macro and micronut rient contents for faster absorption by the plant  
4 Classifications  
For the purposes of this standard there  shall be two classes of organic fertilizer:  
4.1 Pure Organic Fertilizer  
4.2 Fortified Organic F ertilizer  
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©SWASA 20 14 – All rights reserved                                                  3 
 5 Requirements  
5.1 General  
Organic fertil izer shall  conform to the requirements specified in this standard.  
5.2 Physical  
An organic fertilizer must be substantially decomposed as evidenced by the following 
characteristics: 
5.2.1 Material  
The original materials shall be biodegradable  and free fro m plant and animal pathogens . 
5.2.2 Colour  
The c olour of organic fertiliser shall be from brown to black. 
5.2.3 Texture  
Organic fertiliser shall have a friable soil-like texture. 
5.2.4 Moisture Content  
The moisture content shall not exceed  30 %. 
5.2.5 Odou r 
5.2.5.1 Organic fertiliser shall emit an odour of a completely  decomposed substrate. 
5.2.5.2 Pure organic fertiliser shall not emit the original or partially decomposed substrate. 
5.2.6 Organic  matter 
Either pure or fortified, organic fertilizer shall co ntain at least 20% organic matter .  
5.2.7 Carbon nitrogen ratio 
C: N ratio shall not be higher than 20:1. 
5.2.8 Temperature 
The temperature of the product shall not be higher than 30 oC. 
5.2.9 Germination  test 
The product shall show a percentage (%)  seed germination higher or equal with the control or 
check  plant.  
5.3 Nu trient Content  
Nutrient content shall be as specified in Table 1.  
Table 1: Specifications  of pure/fortified organic fertilizer  
Specification  Level  
Total NPK  1.5 % min  
C:N 20:1  
Moisture co ntent  < 30 %  
Organic matter  ≥ 20%  
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  5.4   Levels of  pathogens for organic fertilizer  
Organic fertilizer shall be free from animal and plant pathogens .  
Table 2: Levels of pathogens for organic fertilizer  
 
Specification  Level  
Faecal streptococci  < 5 × 102  colonies/g  
 
Total coliform s < 5 × 102  colonies/g  
 
Salmonella  0 
 
Infective parasites  0 
 
  
5.5 Allowable levels of heavy metals in organic fertilizer   
 
                      Table 3:  Allowable level of heavy metals in organic fertilizer  
 
Heavy metal  Maximum allowable level in com post 
(mg/ kg dry weight)  
Pb 400 
Hg 5 
Cd 5 
As 5 
Cu 300 
Cr 150 
Ni 50 
Zn 50 
 
5.6 Presence  of weed seeds 
Seed s may be present but no viable weed seeds shall be present. 
5.7 Absence of Foreign Materials 
Plastics,  aluminium  wrappe rs,  stones  and  other  inert  materials  shall   be  totally removed from 
the product. 
 
6 Sampling 
Organic fertilizer must be sampled in accordance with SZNS 011 and ISO 8358.  SZNS  037:201 4 
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©SWASA 20 14 – All rights reserved                                                  5 
 7 Test Methods 
Testing shall be  carried out  in accordance with the following methods: 
7.1 Moisture and volatile content – Annex A; 
7.2 Organic matter – Annex B; 
7.3 Organic carbon – Annex B; 
7.4 Germination test – Annex C; and 
7.5 Total nitrogen – Annex D. 
8 Packaging 
8.1 Material 
Organic fertilizer weighing more than 5kg shall  be packed in woven polypropylene sack 
conforming to ISO 23560  with polyethylene liner while those weighing 5 kg or less must be packed 
in polyethylene bag with a suitable thickness to afford maximum protection from normal hazard 
of transportation and handling. 
8.2 Sizes  
Organic fertilizer shall be packed  with a tolerance of ±0.4 % as shown below: 
Table 4: Allowable tolerance sizes for fertiliser bags  
 
9 Marking and labelling  
9.1 Declarations shall be legibly and indelibly marked on a uniform and contrasting background in 
accordance ISO 7409 . 
9.2 The following declarations are examples of what may appear on fertiliser containers or labels : 
9.2.1 Left panel  
a)  Manufacturer/distributor , name and address  
b)  Date of formulation  
c) Lot number  
9.2.3 Front  
a)  Name of material pure or fortified organic fertilizer),  
b) Trade name or brand name  
c) Guaranteed analysis  
i.  Total N (%)  
 Ammoniacal nitrogen (%)  Mass, net weight (kg)  Allowed variance (Tolerance), in grams  
50 ± 200  
25 ± 100  
10 ± 40 
5 ± 20 
1 ± 4 SZNS  037:201 4 
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   Nitrate nitrogen (%)  
ii. Total P 2O5 (%) 
 Available P 2O5 (%) 
iii. Total K 2O (%)  
 Water -soluble K 2O (%)  
iv. C:N ratio  
v. Moisture content  
9.2.4  Optional   
a) Animal or plant substrate without ratio.  
b) Trace elements and secondary elements  
NOTE: Parts per million (ppm) for each element, if any.  
9.2.5 Back  
a) Contents (Net mass, in kg),  
b) Net mass in kg ,  
c) Harmonized system classification number.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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 Annex A  
(informative)  
Determination of total water (Thermal Oven Method)  
A.1     This method determines total water in mixed fertilizers.  It is not applicable to yield samples 
of volatile substances other than water at drying temperature. 
A.2 Apparatus 
A.2.1 Constant  temperature oven 
A.2.2 Weighing dish with cover 
A.2.3  Desiccators containing anhydrous magnesium perchlorate or other suitable desiccant. 
A.3 Procedure 
A.3.1 Weigh 2 g of sample into a tared weighing dish. 
A.3.2 Place the dish, with cover removed, in the drying oven at 100 oC ± 1 oC for 5 hours. 
A.3.3 Remove from the oven, cover the dish and cool in the desiccator. 
A.3.4 Weigh  and determine the weight loss. Repeat procedure until constant weight loss is attained. 
A.4 Calculation 
 
Weight loss (g) 
% Total Water =   ____________________     x  100                             
 
Weight of sample (g) 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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  Annex B  
(informative)  
Determination of ca rbon and organic matter (Walkley - black method)   
B.1 Reagents 
B.1.1 Potassium dichromate solution.   Dissolve 49.04 g of K2Cr2O7 in 1 liter of distilled 
water. Dichromate should be dried at 200 oC for 2 hours. 
B.1.2 H2SO4, concentrated. 
B.1.3 H3PO4, 85 %. 
B.1.4 Diphen ylamine indicator.   Dissolve 0.5 g diphen ylamine in 20 mL distilled water. Add 
100 mL H2SO4 and mix. 
B.1.5 FeSO4 solution, 0.5 N.  Dissolve 140 g of FeSO4 or 200 g of Fe(NH4)2SO4 in 15 mL 
concentrated H2SO4. Make up to 1 liter with distilled water. 
B.2 Procedure 
B.2.1 Weigh 0.025 g sample. 
B.2.2 Place in Erlenmeyer flask and add 10 mL K2Cr2O7. 
B.2.3 Add 20 mL H2SO4. 
NOTE If colour  changes  immediately  to green , reduce  the sample . Stand for 30 minutes. Dilute to 200 
mL. 
B.2.4 Add 10 mL of 85% H3PO4, then add 1.0 mL diphenylamine indicator. 
B.2.5 Titrate  against FeSO4, end point is blackish green. 
B.3 Calculation 
 
B.3.1 Calculate for % organic carbon (o.c.) 
 
N of FeSO4 =   10 
 ___________________  
 
Vol. of FeSO4 used 
 
 
% o.c. =  (V blank – V sample) x N FeSO4 x 0.399 
 _______________________________________  
 
Weight of sample 
  
B.3.2 Calculate for % organic matter 
% organic matter = % o.c. x 1.72 
 
 
 
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©SWASA 20 14 – All rights reserved                                                  9 
 Annex C  
(informative)  
Germination test  
1CCME Compost maturity criteria  
The CCME deemed a compost mature if it meets two of the following requirements: 
◊ C:N ≤ 20 
◊ Oxygen  uptake ≤ 150 mg O2/kg volatile solids/hour 
◊  Germination rate of cress (Lepidium sativum) and radish (Raphanus sativus) seeds in compost must 
be greater than 90 % of the germination rate of the control sample, and plant growth of the compost-
soil mix must not differ by greater than 50 % when compared to a control. 
OR 
◊ Compost  must be cured for at least 21 days; and 
◊ Compost will not reheat upon standing to greater than 5 oC above ambient Philippine temperature. 
OR 
◊ Compost  must be cured for a minimum of 21 days, and 
◊ Reduction  of organic matter must be > 60 % by weight. 
OR 
◊If no other determination of maturity is made, the compost must be cured for 6-month period under 
aerobic conditions. This curing stage begins when the pathogen reduction process is complete and the 
compost no longer reheat s to thermophilic temperatures. 
 
Table C.1 – Classification of compost 
 
 Category  
CCME (provinces and territories)   A, B  
2 BNQ AA, A, B  
3 AAFC  One category based trace element limits B  
 
NOTE  
1 Canadian Council of Ministers of the Environment 
2 Bu reau de Normalisation du Quebec 
3 Agriculture and Agri-Food Canada    
Under the BNQ standard, compost may be categorized as AA, A or B. Types AA and A are of 
higher quality than type B. The requirements for Type B compost are considered to be the 
minimum necessary to obtain good compost. Under the CCME guideline, two compost categories 
have been established. Category A compost can be used for all types of applications: on 
agricultural lands, in residential gardens, in horticultural operations, or nursery and other 
enterprises. Category A criteria for trace  elements  are  achievable  using  source  separated  
municipal  solid  waste feedstock. Category B compost  has restricted  use.  It may be controlled  
under provincial or territorial regulations. For ‘fertilizer’ use, the AAFC recognizes only one class 
of compost, reflective of product safety criteria. It is based on the limits of category and type B 
compost for trace elements and reflects the requirements of the standards for pathogenic organism, 
maturity and the presence of sharp objects. 
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  Due to the variability of results and variations on the germination test procedures by many 
scientists, Warman (1999) suggested that more research using different test plants and other 
bioassay procedures must be done in order to achieve a universal test procedure for evaluating 
compost maturity. 
 
*CCQC Compo st maturity  index 
 
The CCQC uses a minimum of three parameters: 
◊ C: N ≤ 20 
◊ Group A test  
o Carbon dioxide release or respiration 
o Oxygen demand 
o Dewar self-heating test 
◊ Group B tests 
o Ammonia: nitrate test 
o Ammonia concentration 
o Seed germination or plant growth test 
Table C.2 – Compo st maturity  index 
 
Method   Units  Ratings  
Very mature  Mature  Immature  
CO 2 test  C g-1 day -1 < 2 2 - 8 >8 
Ammonia: Nitrate  No units  < 0.5  0.5 - 3 >3 
Total ammonia  Mg kg-1, dry 
basis  <100  100<500  >500  
Seed germination  % of control  >90 80 - 90 <80 
Plant trials  % of control  >90 80 - 90 <80 
 
*California Compost Quality Council 
 
Plant assay for determining compo st quality 
Germination is the emergence and development of the seedling to a stage where its essential 
structures indicate whether or not it is able to develop further into a s atisfactory plant under 
favourable conditions in soil (Basra, 1995). 
Zucconi et al. (1981) proposed germination tests using Lepidium sativum L. and compost  extract 
to determine compost maturity.  Some modifications to the procedure such  as  seed  soaking, 
direct  seeding into  compost or  compost-peat mixture,  use  of  centrifuging  instead  of  filtering  
to  separate  compost  from  the supernatant have been made  (Inbar et al., 1990; Inbar et al., 
1993; Grebus et al., 1994; Keeling et al., 1994; Gajdos, 1997; Warman, 1999; Buckerfield et al., 
1999). Variations in the test plant species have also been made such as the use of Chinese cabbage SZNS  037:201 4 
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©SWASA 20 14 – All rights reserved                                                  11 
 (Warman and Termeer, 1996; Warman, 1999), ryegrass (Inbar et al., 1993), and komatsuna 
(Chanyasak et al., 1983). 
Plants  as  indicators  have  been  used  along  with  chemical  assay  in investigations on 
compost and vermicompost maturity. Radish and marigold are among the commonly used in 
plant bioassays. 
Plant seeds  t hat  may  be used  f or ge r mi n a ti on  test:      Radish, m a r i g o l d , or 
Chinese cabbage Seed vigor test   (Source: Ang Lopez, 2001 ) 
Line a petri dish with filter paper moistens with deionized water. Place 20 test seeds    on the filter 
paper and keep the petri dish in the dark at 22 °C. Count the number of germinated  seeds after 5 
days.  (Germination count must not be less than 85 %.  Adjustment on the number of seeds to be used 
in the Germination Count Test must be adjusted if the germination in the seed vigor test is less than 85 
%. 
Germination test using 1 : 4  (w/v) or 1:8 (w/v) Compost  extract  (Warman 1999) 
Line petri dishes (9 cm) with Whatman No.1 paper. Moisten the filter paper with 5 mL of the 
extract . The filter  paper  in control  petri dish must  be moistened with 5 mL of deionized water. 
In three replications, place 30 seeds of radish, or marigold placed in the dishes and germinate 
in the dark at 20 °C. Take germination count after 48 hours. 
Direct seed germination test (Warman 1999b) 
The direct seed germination test (Warman, 1999b) on radish, marigold and upland cress, done in 
three replicates, was conducted by mixing vermicompost with Pugwash sandy loam soil in 5 % and 
10 % (w/w) combinations. Seventy-five mL of moist vermicompost soil mix was placed in each 
cell pack. Each treatment was seeded with 30 seeds of each test plant. Moisture in the cell 
was maintained by adding deionized water as required.  The cell packs were kept under 12 to 14 
hours of light daily at 24 °C ±2 ºC in the plant growth chamber. Germination count was taken 
ten days after seeding, after which, the plantlets were thinned down to 2 in each cell. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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  Annex D  
(informative)  
Determination of total nitrogen  
D.1 Reagents  
D.1.1  H2SO 4, concentrated.  
D.1.2  Salt mixture. Mix together 100 g K 2SO 4, 10g CuSO 4 • 5H 2O and 1.0 g Se or 1.4 g SeO 2. 
D.1.3  Sodium hydroxide, 40 %. Dissolve 400g NaOH flakes in 1 liter distilled water. Cool in water 
bath with running water.  
D.1.4  Boric acid, 2 %. Dissolve 20 g boric acid in 1 liter distilled water. Heat to hasten dissolution . 
D.1.5  Mixed indicator. Dissolve 0.099 g bromocresol green and 0.066 g methyl red in 100 mL 
ethanol.  
D.1.6  Standard H 2SO 4, 0.03 N.  
D.2 Procedure  
D.2.1  Digestion  
NOTE – Run a blank test on the reagents . 
D.2.1.1  Nitrate free samples (Organic fertilizers an d samples that do not contain nitrates).  
a) 1.0 g sample  
b) 2.0 g salt mixture  
NOTE Shake or mix before digestion  
c) 40.0 mL conc. H 2SO 4 
d) Dilute to 250 mL after cooling and mix.  
D.2.1.2  Organic fertilizers and samples containing nitrate (NH 4NO 3, KNO 3, etc.) 
a) 1.0 g sample or 0.5 g sample  
b) 3.0 mL H 2SO 4 – salicylic acid mixture (1.0 g salicylic acid + 30 mL conc.  
H2SO 4) 
1) Thoroughly mix and let it stand for 30 minutes.  
2) Add 5.0 g sodium thiosulfate (Na 2S2O2) 
3) Shake and let it stand for 5 minutes. Di gest with slow heating (preheated at setting 5) until foaming 
lessens (5 to 10 minutes). Let cool. Continue digestion until clear solution results. Dilute to 250 mL 
after cooling and mix.  
D.2.2 Distillation  
Take 20 mL aliquot of the solution and transfer t o a distilling apparatus. Add 25 mL of 40 % NaOH. 
Collect 50 mL to 75 mL distillate using a receiver containing 10 mL of 2 % boric acid solution and 
0.5 mL mixed indicator. Titrate distillate with 0.03 N H 2SO 4. 
 
 
 
 
 
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©SWASA 20 14 – All rights reserved                                                  13 
 D.3 Calculation  
 
(V in mL H 2SO 4 – V in mL Blank) x N H 2SO 4 x 14/1000 x D.F.  
% N = __________________________________________________________  x 100  
 
Weight of sample  
 
where:  
D.F. is the dilution factor.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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  Bibliography  
Ang Lopez M. 2001. Quality and Maturatio n of Vermicompost Derived from Different  
Feedstocks. MSc. Thesis. Nova Scotia Agricultural College/ Dalhousie University. Nova 
Scotia, Canada.  
Fertilizer Regulatory Policies and Implementing Guidelines or “Bluebook”  
Warman P.R. 1999b. Evaluation of seed ge rmination and growth tests for assessing compost 
maturity. Compost Science and Utilization, 7(3): 33 -37. 
Warman, P.R. 1999a. Lab Methods for Compost Quality Evaluation, CBA Press, Inc. Truro, 
NS, Canada, 27 pp.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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ICS 65.020 
Price  based  on 14 pages.