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4.0 BACKYARD OR HOUSEHOLD LEVEL COMPOSTING Given the thin, shallow, clayey and acidic soils in Montserrat, composting has the

potential to make significant improvements to agriculture, as well as diverting waste

from New Windward landfill.

In May 2001, the Montserrat National Trust held a series of environmental

workshops. As part of these workshops, information sessions for the public were held,

to educate some local farmers and gardeners about composting. Additionally, a

special presentation was made to the Farmer’s Union, as well as members of the Davy

Hill Community Action Group. Members of St Peter’s Mother’s Union were invited

to participate in a composting survey (they declined) and were asked whether they

needed assistance with composting – a few members requested information. Some

home composters were visited to discuss the state of their compost heaps and

suggestions were made for changes which could improve the efficacy of composting.

Two demonstration compost bins were constructed, by Pete Hobbis, at the Montserrat

National Trust. One was built from new timber and the other was constructed from

reused timber pallets, which can be easily obtained gratis from Rams Emdee

supermarket or from the port at Carr’s Bay. Mappie (Philemon) Murrain, botanical

gardens manager at the National Trust, constructed two demonstration pits or

trenches, examples of traditional Montserratian methods of composting. A wire cage

containing composting leaves, and a plastic bin for composting kitchen and garden

wastes, imported from Canada, were also on display during the environmental

workshops.

Promotional leaflets for backyard composting, giving brief instructions of what to

compost and how to compost, were produced and some were distributed through the

National Trust.

4.1 DESCRIPTION OF COMPOSTING PROCESS AT HOUSEHOLD LEVEL.

A householder may compost using an open heap, a bin or a trench. Successful

backyard composting depends on obtaining and maintaining a high enough

temperature to enable compost to be produced in a reasonable time, and to kill any

62

plant or human pathogens. It is also necessary to have sufficient moisture and oxygen

available to support the micro-organisms who actually do all the work of composting

for you while you wait. The advantage of using a bin, of dimensions approximately

1m x 1m x 1m, is that it can hold the waste in a cube shape which enables it to heat up

and retain its heat180. The open heaps are much easier to build and turn, but do not

heat up as effectively. Using a trench is an excellent method of retaining moisture,

during the dry season, and a compost pit is the easiest to turn, of all the methods.

Figure 4.1 Demonstration compost bins used at the Montserrat National Trust

Figure 4.2 Compost pit used as a demonstration model, at the Montserrat National Trust

63

Forming the composting mixture into a pile helps it to retain moisture and stops if

from cooling down. A taller vertical stack is better than a shallow spread-out heap to

improve drainage and prevent waterlogging, especially during the wet season. A

compost bin is more of a deterrent to animals than an open heap. Compost pits or

trenches tend to be useful in areas which are very arid, where moisture must be

conserved at all costs, or in very cool regions where they help to retain heat181. During

the wet season, compost pits can easily become waterlogged.

A compost pit is made by digging a trench several feet deep, lining with plastic and

filling with alternate layers of garden wastes and manure, to form a pile extending a

few feet above the ground. The top of the compost is covered over with another

plastic sheet, punctured with a few small holes to encourage airflow. The compost pit

is turned and watered every second day.

For countries like Montserrat which have high evaporation rates, a compost heap with

an initial water content of 65% can have its moisture content drop to 20 to 30% in a

period of only a week during the dry season. For each cubic yard of finished compost,

200 to 300 gallons of water may need to be added during the composting process182.

When the compost is sufficiently wet, it will have the consistency of a squeezed-out

sponge. The compost in the bins at the Natural Trust were given one 5-gallon bucket

of water daily during the dry season. Due to time constraints no experience was

gained during the wet season to determine whether the addition of moisture was

necessary or desirable. The moisture content of the demonstration compost piles

should be noted if a follow-up visit to Montserrat is made in October.

To obtain good quality compost within a reasonable time frame, it is necessary to use

a mixture of wastes to give a carbon: nitrogen ratio of approximately 30:1 in the

initial stages of composting. The carbon: nitrogen ratios of some wastes which could

be used by a farmer or gardener as composting feedstocks, or which could be

composted commercially, are tabulated overleaf. Note that wastes such as meat

scraps or septic tank sludge should never be composted by a backyard gardener, they

are merely included in this table for the sake of completeness, for comparison

purposes and so that they can be referred to in later chapters.

64

CARBON: NITROGEN RATIOS OF COMMONLY COMPOSTED FEEDSTOCKS

MATERIAL %N C:N RATIO

Bread 2.10

Cabbage 3.6 12

Cardboard 0.10 400-563

Coffee Grounds 20

Cow Manure 2.4 19

Corn Cobs 0.6 56-123

Corn Stalks 0.6-0.8 60-73

Cotton Seed Meal 7.7 7

Ferns 1.15 43

Fish Scraps 10.6 3.6

Fruit 1.4 40

Garbage (Raw) 2.15 15-25

Grass Clippings 2.4 12-19

Hardwood Bark 0.241 223

Hardwoods (Average) 0.09 560

Hay (general) 2.10 -

Hay (legume) 2.5 16

Hen Manure 8 6-15

Horse Manure 1.6 25-30

Leaves 0.9 54

Lettuce 3.7 -

Newsprint 0.06-0.14 398-852

Onion 2.65 15

Paper - 100-800

Peppers 2.6 15

Potato Tops 1.5 25

Poultry Carcasses 2.4 5

Raw Sawdust 0.11 511

Rotted Sawdust 0.25 200-500

Sewage Sludge 2-6.9 5-16

Sheep Manure 2.7 16

Slaughtering Wastes 7-10 2-4

Softwood Bark 0.14 496

Softwoods (Average) 0.09 641

Tomato 3.3 12

Turnip Tops 2.3 19

Vegetable Produce 2.7 19

Water Hyacinth - 20-30

Whole Carrots 1.6 27

Whole Turnip 1.0 44

Table 4.1 Carbon : Nitrogen Ratios of Some Commonly Composted Wastes

65

Usually, several wastes must be mixed together to get the optimum C:N ratio for

composting. The figures given in the above table could be used if a farmer was

concerned about having the best possible C:N ratio for faster composting. For

example, if a Montserratian farmer has a quantity of say 50 kg of mixed fruit waste

with a C:N ratio of 40 and 10 kg of leaves with a C:N ratio of 54, how much sheep

manure, with a C:N ratio of 16, should be added to get the best C:N ratio for optimum

composting?

C:N overall = C:N fruit waste x mass fruit waste + C:N leaves x mass leaves + C:N manure waste x mass manure

Mass fruit waste + mass leaves + mass manure

30 = 40 x 50 + 54 x 10 + 16 x mass manure

50 + 10 + mass manure

30 = 2000 + 540 + 16 x mass manure

60 + mass manure

1800 + 30 mass manure = 2540 + 16 x mass manure

14 mass manure = 740

mass manure = 53kg ≈ 50kg

In deciding what to compost, a farmer may also take into account the specific nutrient

needs of the plant. For example, fruit and flowers need high levels of phosphorous

and potassium whereas lawns need high levels of nitrogen183. Nitrogen contributes to

the production of leaves, stems and foliage, phosphorous is necessary for the

promotion of root development and to initiate flowering and potassium is necessary

for the production of starches184. Potassium is essential for tuberous plants such as

sweet potatoes, as well as forming strong stems and starchy fruits, and is particularly

beneficial for light, sandy soils. A comparison of the nutrient levels of different types

of manures is given below in Table 4.2:

MANURE %MOISTURE %NITROGEN %PHOSPHOROUS %POTASSIUM

Cattle 80 1.67 1.11 0.56

Horse 75 2.29 1.25 1.38

Sheep 68 3.75 1.87 1.25

Pig 82 3.75 1.87 1.25

Hen 56 6.27 5.92 3.27

Table 4.2 Nutrient Content of Different Types of Manure Used in Composting.

66

Considering the data in the above table, it would seem that hen manure is ideal for all

applications, whereas for flowers or fruit with a high potassium requirement, horse

manure is ideal, and pig or sheep manure is the best for all other applications when

hen manure is unavailable. (There are relatively few chickens on Montserrat, though

some have recently been imported to give the industry a boost185). It must also be

borne in mind that pig manure has a high moisture content and that both pig manure

and chicken manure should be blended with carbonaceous materials when

composting186.

Another important consideration in deciding what to compost is whether plant

diseases or weeds will be spread by the use of compost. Further research is necessary

to determine which of the weeds listed in section 1.2.12. have seeds which are

inactivated at the sort of temperatures which are reached in a backyard compost heap,

and also which of the plant diseases listed in section 1.2.11 can be spread by the use

of compost made from diseased plants. Some plants which are found in typical

Caribbean gardens are poisonous to humans and these plants should not be

composted. Poisonous plants found in the Caribbean include the Poinsettia,

(Euphorbia pulcherimma), other species of Euphorbia, the Frangipani (Plumeria spp.)

and the Manchineel (Hippomane mancinella), all of which have an irritating sap187.

The latex which exudes from cut surface such as branches which have been pruned

from the trees is harmful to human skin, hence it is recommended that green waste

from these plants not be composted. The fishtail palm (Caryota mitis) has fruits which

have crystals on their surface which sting the skin. Of even greater concern are the

highly poisonous plants Datura (Datura), Dumb Cane (Dieffenbachia) and Oleander

Nerium which contain toxic substances that could easily kill a small child if ingested.

Even just touching the plant and then inadvertently touching one’s lips or eating

without washing one’s hands is very dangerous. These plants should never be touched

without gloves, not for composting or any other reason. They should never ever be

added to a compost heap, especially one that is easily accessible to children and small

animals.

Other factors affecting the composting process include pH, moisture and surface

area/particle size. Usually it is not necessary for a farmer to worry about pH, and

especially not a backyard gardener. However it may be helpful to keep in mind that

67

fruit and vegetable wastes have a low pH188, and therefore composting fruit and

vegetable wastes alone may not be helpful for Montserrat’s acidic soils. However, if

these wastes are mixed with other materials such as shredded green waste, then there

should be no such problems. It is necessary to avoid anaerobic conditions when

composting, as these tend to lower the pH189.

Moisture levels should preferably be in the range 40-60% for optimum composting190.

To determine whether this level has been reached, the home composter should

squeeze a handful of compost. If it crumbles, then it is too dry. If a huge amount of

water runs out of it, then it is too wet. If just one drop squeezes out of it, and it feels

moist but not wet, then it is just right. If the pile is too wet, it can be watered,

preferably while it is being turned to make sure that the entire pile is at the same

moisture level, as much as possible. Adding dry materials such as shredded green

waste not only helps to reduce excessive moisture levels but also helps to maintain

structure for improved aeration. Shredding green waste greatly improves its surface

area, enabling it to break down faster. As there is only one shredder on the island, a

machete or pruning shears may need to be used for backyard gardeners to cut their

green wastes into smaller pieces.

Table 4.3 below (continued overleaf) contains a list of some typical feedstocks which

may be used for home composting, with some of their characteristics191. C:N ratio and

nutrient content have already been considered in Tables 4.1 and 4.2, however

structure, moisture and degradability are included in the table below, as well as some

general disadvantages of using certain feedstocks or pretreatment which is necessary

to make them more useful.

TYPE OF

WASTE

C:N RATIO,

NUTRIENTS

STRUCTURE,

POROSITY

MOISTURE

CONTENT

DEGRADABILITY TREATMENT

REQUIRED

CAUTIONS

Poultry

Manure

10 Poor Moist Good Bulking

Material

Odour

Poultry

manure

(with litter)

13-30 Medium Low-dry Medium - Odour

Manure(ca

ttle,

undried)

8-13 Poor Liquid Good Mix with dry

matter

Odour

Table 4.3 (cont’d overleaf) Characteristics of Typical Feedstocks Used in Home Composting. (Dougherty, 1999)

68

TYPE OF

WASTE

C:N RATIO,

NUTRIENTS

STRUCTURE,

POROSITY

MOISTURE

CONTENT

DEGRADABILITY TREATMENT

REQUIRED

CAUTIONS

Manure

(pig)

5-7 Poor High Good - Odour,

moisture

Dried cow

manure

20 Medium Medium High - -

Manure

with straw

25-30 Good Good Medium - -

Horse

manure

25 Good Good Medium - -

Vegetable

wastes

13 Poor Moist High - Low pH,

odour

Bark 100-300; low

P; Ca; low pH

Very good Medium;

good

Very good Pre-grind -

Sawdust

(fir)

~230 Very good ≤50%, good Excellent Already ground -

Aged

sawdust

<100 Very good ≤50%, good Poor Already ground -

Cardboard 200-500 Medium to poor Very low Very good Shred Boron,

colours

Wood ash

(NOT

volcanic

ash!)

N/A; K-Ca-

rich; high in

heavy metals

Poor Very low None None Metals, high

pH

Fruits Poor in P, Ca Poor Medium Fair to good Lime addition Low pH

Garden

wastes

20-60 Good Medium Medium Grinding -

Green

foliage

30-60 Medium to good Good/dry Good - -

Leaves - Good - - - Matting

Grass

clippings

12-25 Poor Moist High Bulking

material, pre-

drying

Odour

Slaughter

wastes

15-18 Poor Moist High - Odour

Food

scraps

<25, high K,

salt

Very poor High Very high Bulking

material

Pathogens,

salt

Coffee

grounds

- Medium Medium to

high

Medium - -

Table 4.3 (cont’d) Characteristics of Typical Feedstocks Used in Home Composting. (Dougherty, 1999)

69

Important considerations in backyard composting include ensuring high enough

temperatures are reached and that the aerobic bacteria which carry out the composting

process have sufficient oxygen to survive and reproduce. To avoid anaerobic

conditions which lead to odour and attract vermin, as well as to achieve high

temperatures for faster composting, it is necessary to ensure that the compost is

sufficiently aerated. Usually, this is achieved by turning the compost. Sometimes,

when the trench or pit method of composting is used, perforated agricultural pipes

may be used to form air channels in the compost pile192.

It is highly unlikely that any farmers or gardeners on Montserrat have a soil

thermometer. To determine whether a compost pile is heating, the farmer can insert a

hand in the pile to see how hot it is. However, for those who do not like handling

immature compost (i.e. the majority of Montserratian farmers and gardeners), a metal

bar such as a crowbar, reinforcing rod or steel rule can be used to determine whether

the pile is heating well. The pile’s temperature is over 50°C if the hot end of the metal

bar cannot be touched for more than about three seconds without feeling

discomfort193.

To avoid odour and vermin it is recommended that if fresh kitchen wastes are added

to the compost heap, they should be buried well below the surface. Adding wastes

which have an open structure (e.g. shredded green waste) to the compost heap will

also help to trap air and keep the compost aerobic.

Rapid composting occurs at temperatures of 32-60°C, and a temperature of 40°C

should be attained for at least 5 days to significantly reduce pathogen levels in

compost, with the temperature exceeding 55°C for at least 4 hours during this 5-day

period. To further reduce pathogens, it is recommended that temperatures of 55°C

should be attained for at least 3 days for aerated static piles and 15 days for windrow

systems, with at least 5 turnings194 195. These are the temperature standards which the

USEPA mandates for sanitising sewage sludge compost.196 Backyard compost heaps

have obviously much lower levels of pathogens than septic tank sludge, however

some pathogens such as Salmonella can still cause problems, hence it is

recommended that a temperature of 55°C be exceeded where possible.

70

High temperatures in a backyard compost heap are affected by the size of the compost

pile, the ambient weather conditions, the amount of aeration, the particle size or

texture of the feedstocks in the pile, moisture level, carbon to nitrogen ratio and the

composition of the feedstocks used to build the pile.197

Backyard compost heaps are less likely to achieve high temperatures than carefully

controlled large-scale municipal solid waste facilities. However they are still able to

achieve some levels of pathogen reduction. Pathogen reduction is caused not only by

heat, but also by micro-organisms in the compost competing for the same food as the

pathogens, inhibiting them, producing antibiotics to kill them and in some cases even

eating them. 198

If lower temperatures are achieved in a backyard compost heap, then these

temperatures must be reached for a longer time e.g. a temperature of 50°C,

maintained for 24 hours, is sufficient to kill all pathogens in compost, whereas a lower

temperature of 46°C may take nearly a week. Pathogens are unable to survive more

than half an hour at temperatures of 55-60°C, however pathogen numbers are

significantly reduced even at temperatures of not greater than 40°C. Temperatures of

45-59°C allow for maximum biodiversity for the fastest possible rate of

composting.199

It should also be noted that high temperatures are not the only means of pathogen

destruction. Predation or inhibition by micro-organisms or other fauna in a compost

heap can accomplish significant levels of pathogen reduction. For example tests

carried out by Meekings (1995) 200 on composts contain Ascaris eggs, one of the most

persistent pathogens affecting humans, revealed significant degeneration and retarded

development of these pathogens at a low temperature of only 30°C. The effect was

attributed to micro-organisms, as other factors which may have caused pathogen

destruction were carefully controlled. Thus while high temperatures are desirable and

lead to faster composting, Montserratian farmers need not worry excessively if their

piles do not heat to extremely high temperatures.

71

Some of the factors described above such as temperature and aeration must be

controlled for composting in any country anywhere. However, one additional factor

which has not been mentioned previously which affects Montserrat with its

pronounced wet season is drainage. Bannochie and Light (1993) suggest that compost

heaps in the Caribbean should be laid on a base of branches, bamboo and coconut

limbs, approximately 50 cm in thickness201. Feedstocks for the composting process

are laid on top of this base, which is designed to allow the compost heap to drain well

during the wet season. During the wet season the top of the compost pile should be

slightly convex if possible to allow water to drain from it. Bannochie and Light also

suggest that during the dry season the top of the compost heap should be slightly

concave to collect and store water. They suggest covering the heap with plastic

sheeting only at night.

4.2 BENEFITS AND DRAWBACKS OF COMPOSTING IN MONTSERRAT General benefits of composting include improvements to the soil structure enabling it

to better retain water and nutrients or fertiliser202, as well as increased soil fertility and

reduced need for fertiliser application. This leads to a reduction in the negative

environmental impacts of fertiliser production and overuse (such as groundwater

contamination and fertiliser runoff which causes algal blooms). Displacing organic

wastes from landfills also reduces the environmental impacts of leachate, which can

contaminate ground and surface water, and the impacts of methane production, which

contributes to global warming. Home composting reduces the cost to the community

of waste collection and landfill disposal, and frees up funds for more essential

services such as education or health.

Improved soil structure leads to increased aeration, improved stability of soil

aggregates203, increased water penetration and retention, increased total pore space in

the soil, reduced bulk density and increased cation exchange capacity. The addition of

compost leads to a small increase in plant nutrient content (not directly comparable

with the use of synthetic fertilisers) and the microbial population of the compost helps

to improve the soil’s resistance to infestations of plant diseases such as the soil

nematodes which cause root rot. This reduces the demand for fungicides and

72

pesticides,204 205 206 207 especially for plants grown in containers. The use of compost

moderates the soil temperature and discourages insects208. Composting leads to

improvements in soil texture which make the soil more workable, as soil crumb

formation is increased and the tendency of the soil to form a crust is reduced.

Compost can also be used as a mulch on top of the soil, to suppress weeds and retain

soil moisture.

For Montserrat, with its soil erosion problems, the use of compost is particularly

beneficial. The disease suppression characteristics of compost are also particularly

beneficial for Montserrat, as compost has been found to increase resistance to

Fusarium, Anthracnose209 (Colletotrichum)210, Pseudomonas (Banana Moko

Disease)211 Pythium and Phytoptera, plant diseases which are prevalent in the West

Indies212 (see section 1.2.11), as well as root rot nematodes213, common insect pests in

the Caribbean. Compost is also particularly good for protection of plant disease

affecting peppers, lettuce, cabbage214, squash, cucumbers215, beans and tomatoes,

plants which are commonly grown in Montserratian farms and gardens.

Composting wastes and returning them to the soil is much more beneficial than the

alternative of burning them. In Montserrat, in 1993 when livestock were more likely

to be tethered, it was noted that livestock owners set fire to sloping pastureland to

remove older plants and permit the growth of younger fodder which is easier for the

animals to eat216. This burning tended to be carried out just before the onset of heavy

rain. Slash and burn agriculture has also been practised in Montserrat for centuries.

The effect of burning crop residues or grasses on the soil is to raise soil pH and

exchangeable potassium, but it may reduce total phosphorous, total Kjeldahl nitrogen,

organic matter content, cation exchange capacity, exchangeable sodium, calcium and

magnesium, manganese, iron and zinc217. In contrast the use of compost formed from

the same material as that which is customarily burnt tends to slightly increase the

nutrient levels and their availability, and also increase the soil’s organic matter

content, with all the attendant benefits that this brings. (Although one study of burnt

soil218 shows that available nutrients actually increased following a light fire which

left trees intact). Even if there is no shortage of nitrogen, phosphorous and potassium

in burnt soils, plant growth may be inhibited by the production of phytotoxic

73

compounds at the temperatures of the fire and the negative effects of these phytotoxic

compounds may be suppressed by the use of mature compost219.

Slash and burn agriculture tends to reduce the soil’s microflora, whereas the use of

compost leads to an increase in the soil’s microbial population220.

In Montserrat, approximately 10,290 kg of fertiliser were imported last year, for a cost

of $22,311.00 Eastern Caribbean dollars221. Given the unsustainable nature of

Montserrat’s economy, there is a huge financial incentive to use compost as an

alternative to fertiliser or to reduce the quantity of fertiliser which needs to be applied

to the soil. As Montserrat has acidic volcanic soils, the use of compost could also

raise the soil pH without the expensive addition of lime, thus also enabling the growth

of beneficial soil bacteria, and reducing the amount of magnesium, potassium,

calcium, copper and molybdenum which would otherwise be leached out of the acidic

soil during the wet season222. Even if lime is to be added, the amount of lime which is

needed is reduced if compost is also applied to the soil223.

Montserrat is far from being self-sufficient in agriculture. Last year, 1,882,796 tonnes

of food were imported, for a cost of $7,696,098224. The use of compost could improve

agriculture and reduce this dependency on imports, as well as possibly leading to

improvements in nutrition and health. Howard (1943)225, comments that

“When the health and physique of the northern Indian races were studied in detail,

the best were those of the Hunzas, a hardy, agile, and vigorous people, living in one

of the high mountain valleys of the Gilgit Agency…There is little or no difference

between the kinds of food eaten by these hillmen and the rest of northern India. There

is, however, a great difference in the way these foods are grown…[T]he very greatest

care is taken to return to the soil all human, animal and vegetable [refuse] after being

first composted together. Land is limited: upon the way it is looked after, life

depends.”

Increased use of compost could have a positive social impact, by reducing farmers

and gardeners’ spending on fertiliser and allowing the diverted funds to be spent on

other more useful goods and services, supporting the local economy.

74

As Montserrat’s landfill is unlined, the increased use of composting would help to

reduce groundwater contamination from leachate.

With so many potential benefits, why isn’t everyone on Montserrat composting

everything in sight? Well, it must be borne in mind that there are a number of

potential problems associated with composting, which must be carefully managed.

Potential drawbacks associated with the use of compost include contamination of soils

with potentially toxic elements and compounds226, such as those contained in

pesticides sprayed on garden wastes, or those contained in the treated timber used to

make the compost bin, or copper chromated arsenic,227 contained in sawdust made

from treated timber waste. If weeds which have gone to seed are added to the compost

bin, then some seeds may not be inactivated at the temperatures reached in backyard

composting. Some plant diseases may also be inadvertently propagated by

composting, if diseased parts of plants are added to the compost bin.

Composting should not normally cause any health problems to the average person,

however one of the drawbacks of home composting is that people who suffer from

asthma may be adversely affected by dust which is stirred up when the compost is

turned. Additionally, compost heaps tend to contain a fungus Aspergillus fumigatus

which may cause allergic reactions in some people or may adversely affect those with

depressed immune systems.

Sometimes compost may have a negative effect, for example if the soil is severely

waterlogged then the improved water retention afforded by the compost would

actually make the problem worse228. Using compost for tree planting and forestry

applications may not always be entirely beneficial, especially if it is incorrectly

applied. If compost is added to the soil in the pit in which the tree is to be planted,

then roots find it difficult to cross through the compost modified soil to the

unmodified soil and their spread is limited. Generally improving the soil uniformly

across the entire field with compost avoids this problem of creating an unnatural

interface near the soil’s roots, and gives more successful results. It is important to

ensure that the compost is added to the soil prior to the planting of the trees, otherwise

the compost is likely to be ineffective and would be better utilised elsewhere.

75

In Montserrat, the problem of increased water retention could be experienced during

the wet season, especially around Carr’s Bay where the soil is known to be prone to

waterlogging229, or at St John’s, where the soil has a high capacity for supplying

moisture. The problem is unlikely to occur elsewhere on the island, where the soil has

a moderate or low ability to retain moisture.

If compost is to be used for reforestation of Silver Hill, or for the proposed citrus

orchard at Davy Hill, then it should be applied uniformly to the soil before digging

pits to plant the trees, to avoid the problem of limiting root spread.

One of the main disadvantages of home composting is the time and effort that it takes,

time which could perhaps better be spent on other things. For the elderly, the disabled

or people who are not physically fit, turning compost may be impossible or very

difficult. Composting may also lead to an odour nuisance or an infestation of vermin

such as rats or cockroaches. However these nuisances do not necessarily affect all

composters, if their heaps are properly managed, by turning frequently and burying

fresh food wastes well below the top surface of the compost pile.

Weighing up the benefits and disadvantages of composting, is compost really

necessary or useful on Montserrat? Certainly, it is much more useful than airports,

conferences and consultants, an oversized police force, or the construction of even

more church buildings! In fact, about the only thing the Montserratian farmers need

more than compost is fences to keep out wandering cows, or some other means of

livestock control. However, just because composting could lead to enormous

improvements in agriculture in Montserrat, doesn’t mean that hordes of farmers and

gardeners are keen to compost. We all know that getting more exercise, eating more

green vegetables and not drinking excessively is good for us, but how many people

actually change their behaviour, just because they know that it is good for them.

Similarly, there are other strong motivating factors at work, which prevent the need

for composting from being keenly felt in Montserrat at present. Strategies for the

promotion of home composting in Montserrat, to make it become a more attractive

option, will be discussed in section 3.7.

76

4.3 METHODS OF APPLICATION OF COMPOST In Montserrat, which has pronounced wet and dry seasons and steep slopes, it is best

to apply compost when the wet season is just beginning, to improve the soil’s

drainage ability and prevent erosion and leaching of soil nutrients230. Mulches are best

applied when the dry season is just beginning, to prevent the soil and plant roots from

becoming too hot and to enable moisture to be retained in the soil.

Seeds should be sown or young plants planted out within two weeks of the application

of compost. The compost could be spread uniformly over the entire field and dug into

the soil, or a more targeted application could use mounds of compost or compost

applied in strips between rows of plants. For pumpkins, cucumbers (Cucurbita) and

squash (Cucumis), the use of mounds has been found to be particularly effective.

Compost can be used for germinating seeds. For the majority of seeds, the

recommended potting mixture is one part sieved garden soil, one part compost and

one part sand (by volume), moistened and mixed together well.

Figure 4.3 Compost from the demonstration brush and manure compost bin at Montserrat National Trust is used for composting seedlings, blended in the ratio 3 parts sand: 2 parts soil: 1 part compost.

If compost is to be used as a growing medium in other countries such as the UK then

it is usually mixed with other materials such as bark, peat, or coir (a waste product of

the coconut industry). Chipped bark is unavailable locally in Montserrat, as is peat

(whose use is also undesirable from an environmental point of view), however coir

could be made available provided that someone could process it231. Compost should

not be used on its own as a potting medium, as it has a high pH, high bulk density

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high conductivity, inadequate available nitrogen and phosphorous content, and

excessive content of potassium, compared with plant requirements232.

Trials carried out in the UK show that the addition of 10% compost to soil used for

potted plants can be highly beneficial233. In a series of controlled trials with rye grass,

it was found that adding 10% compost to the soil in the potting mix gave a yield of

2.600 grams of rye grass per pot, whereas the control which had soil only, had a yield

of 1.721 grams per pot. Adding 1% compost gave a yield of 1.958 only, a slight

increase over soil only. Adding 10% compost decreased the soil’s bulk density and

increased the saturated hydraulic conductivity and the available water capacity.

Nitrogen levels for the mixture of soil plus 10% compost were 202 N mg/kg (NO3-N

& NH4-N) after 12 weeks whereas for soil only they were 28 mg/kg. This was in spite

of the fact that 68 mg/kg nitrogen fertiliser was added to the soil whereas only 4

mg/kg was added to the soil plus 10% compost mix. Because green waste compost

had a structure which broke down when it became too moist, it was necessary to add

the compost to soil rather than using it neat.

Trials of compost application to agricultural land have also been carried out in the

UK, to determine the optimum application levels. Green waste compost was applied

at depths of 5cm and 15 cm, and for loading rates of 25, 50, 100 and 200 tonnes/ha.

Growth was most enhanced for application rates of 100-200 tonnes/ha, even though

this exceeds recommended guidelines. The MAFF Code of Good Agricultural

Practice (1994)234 recommends a limit of 250 kg ha-1 y-1 for nitrogen, which gives 25

tonnes/ha as the maximum recommended application rate. However this limit is set by

the European Commission’ s Nitrate Directive and is designed to protect areas which

are sensitive to high levels of nitrate. As Montserrat’s water is primarily derived from

springs whose catchment areas tend to be located on the higher slopes above

farmlands, nitrate contamination is unlikely to be an issue in Montserrat. Hence it is

recommended that compost can be applied to agricultural lands at levels of up to 200

t/ha.

Compost application rates may be limited by their heavy metal content, however this

is primarily a limiting factor for composts made from sewage sludge or contaminated

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municipal solid waste rather than those made from kitchen or garden wastes at a

household or farm level.

Compost should be worked into the first 30 cm of soil, or at least into the first 5-8

cm235. For most plants, only mature compost should be applied, however some plants

such as corn and squash are able to make use of compost which has not yet reached its

final stage of maturity236.

It is possible to apply compost in liquid form as a compost tea. To make compost tea,

fill a porous bag (cloth or woven plastic sack) with compost and place in a large

container of water237. The resulting compost tea liquid can be used after about a week.

One Montserratian farmer, John Keller, fills recycled plastic bottles with a compost

tea, and buries these bottles at regular intervals of approximately 20 cm apart,

throughout rows of plants. Small holes in the plastic bottle allow the compost tea to

seep gradually into the soil, assisting to maintain moisture levels during the dry

season as well as adding nutrients to the soil for the growing plants.

Compost teas have been found to be very effective at suppressing plant diseases such

as fungal infestations, when sprayed onto plants directly rather than being applied to

the soil238. Liquid feeds may be particularly beneficial in Montserrat, where in some

areas the soil is so weak that plants fall out when attempts are made to plant them.

Excessive application of solid compost could lead to too many air spaces in the

soil239.

4.4 CASE STUDIES Three case studies can be considered to illustrate the problems and potential for

backyard or farm scale composting in Montserrat.

Teresa Sillcott, manager of the Grand View Hotel, has a small compost heap in her

garden. The garden is used to produce food for the hotel, including passionfruits,

mangoes, pawpaw, bananas, almonds, herbal teas, spinach, tomatoes, green

vegetables and root vegetables such as dasheen. The compost pile is quite small, has

not been regularly turned and there are problems with vermin such as rats, in the

Baker Hill area. Because of the small pile size the compost does not heat up very

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much. Teresa was unable to attend the workshops at the Montserrat National Trust,

and requested some information about composting, as well as visiting the National

Trust to look at the demonstration composting units. As a result of this visit, she has

obtained some pallets to construct a compost bin, which will improve the shape of the

compost pile. If wire mesh is used in the side walls of the bin, it may also help to

discourage vermin. Teresa is now aware of the benefits of turning and watering

compost, which, if she finds time to do it, will improve the quality of her compost (by

discouraging anaerobic conditions) and increase the speed of composting.

Jean Kelsic is a Montserratian lawyer who has an extremely large garden in

Montserrat’s Old Towne. He has a number of large composting bays constructed of

cement blocks. Leaves are being composted, as well as kitchen and garden waste.

Manure is being dried separately for use on the garden and is not composted together

with carbonaceous materials. The compost piles are at ambient temperature, and are

never turned. The compost is removed from the bays for use in the garden, after 1

year. There do not seem to be any problems with vermin, or odour nuisance.

As a result of publicity about composting which surrounded the environmental

workshops at the Montserrat National Trust, Jean Kelsic requested information about

how to make his compost piles better. He was advised of the benefits of turning, and

of maintaining an adequate C:N ratio. However, in the end Jean decided that he was

quite happy to wait one year, his compost was not causing him any problems at all at

present, and therefore he was happy to continue with what he is already doing.

John Keller is a farmer who grows a variety of fruits and vegetables on a

comparatively large area of land, which he sells in a small stall in the market area of

Salem on Friday and Saturday mornings. The farm is on steeply sloping land which is

exposed to high winds at times.

John has a pond containing water hyacinths, an ideal feedstock for composting as they

have a C:N ratio of 20-30. The use of water hyacinths also helps to keep the compost

pile moist, at least in the initial stages of composting. There are three small compost

piles on John’s farm, spread out at some distance away from each other to minimise

the time spent walking from the area under cultivation to the nearest pile. Turning is

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carried out occasionally and the piles are occasionally watered, however due to the

high windspeeds the compost dries out again particularly quickly.

John Keller’s compost heap was observed on Saturday 30 June 2001. There were

three small piles and as they were so small, they were all at ambient temperature. The

piles appear to contain mainly carbonaceous waste. The compost heaps were very dry

and appeared to have been watered from the top, and the water had not appeared to

percolate through the entire compost heap.

On the day of the visit, the main compost pile near the goat shed was of dimensions

1050mm x 1020mm x 400mm, and was at a temperature of 25.4°C at 10:35 am,

slightly less than the ambient temperature of 27.1°C. This pile was dry, and showed

no remaining signs of recent watering. The water hyacinths which had previously

been added to the compost heap had broken down completely. The second largest

pile, on the lower slopes, had dimensions of approximately 800mm x 800mm x

360mm. Its internal temperature was 28.5°C. Dissolved oxygen level in both piles

was measured as 8mV, which gives a dissolved oxygen level of approximately 4.7%.

The pile on the lower slopes was dry with signs of moisture in its upper surface layer

only. There were traces of dried out fragments of the water hyacinths which had

previously been added to the compost heap, however most of this material had broken

down.

High temperatures in a backyard compost heap are affected by the size of the compost

pile, the ambient weather conditions, the amount of aeration, the particle size or

texture of the feedstocks in the pile, moisture level, carbon to nitrogen ratio and the

composition of the feedstocks used to build the pile. 240 To increase the temperature of

the largest pile near the goat shed, all the material from the second largest pile on the

lower slopes was removed and the two smaller piles were amalgamated into one

larger pile, roughly cubical in shape. The pile was thoroughly wetted while turning,

with several large buckets of water using a metal bucket found on site and water

scooped out from the hyacinth lagoon. By wetting the material while turning it, the

entire pile was wetted, not just the surface layer.

The materials used for the compost appear to be very woody and carbonaceous. It is

suggested that in future some manure be added to the pile to maintain a good C:N

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ratio. On 30 June 2001, a sack of mature brush and manure compost from the

Montserrat National Trust’s demonstration units was added to the compost heap, as a

“starter” or “compost accelerator”. This compost should contain a healthy population

of micro-organisms.

On 30 June 2001, the compost pile was covered with some pieces of corrugated iron

held on site, to insulate the pile and prevent it from drying out under the influence of

the high wind speeds. If a sheet of plastic can be procured, this will be even more

effective. The turning was carried out using shovels found on site. It is suggested that

a garden fork be procured to improve the efficacy of compost turning. Due to the

shortage of garden forks in Montserrat, it is suggested that a fork be procured in the

United States.

Figure 4.4 Corrugated iron was used to provide some shelter from the high wind speeds at The Cot. It is suggested that the pile be kept in its present location where it is less exposed to the wind. (Photo credit: Helen Meekings, 2001)

In future, when turning the compost, it is suggested that the entire heap be moved

aside. The compost can then be turned and put back in its original place, where it is

sheltered from the wind as much as possible. Two buckets of water (at least) should

be added progressively to the compost while turning.

If John Keller’s compost heap is kept covered, and watered very well while turning, it

can be expected to produce compost more effectively at a faster rate.

These three case studies illustrate the following points:

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• Some composting is already being carried out on Montserrat, with a greater or

lesser degree of success.

• In general there is a lack of knowledge of the benefits which could be achieved by

having a cube-shaped pile of sufficient size, turning frequently and maintaining

moisture levels.

• Some gardeners may be happy NOT to turn and water their compost, and just wait

a year before using it, rather than 3 months. The product may undergo anaerobic

decomposition, resulting in volatilisation of nitrogen as ammonia gas and the

formation of organic fatty acids which will not help Montserrat’s acidic soils,

nevertheless a useful product may still result, even if it’s not perfect. (It is possible

for a compost pile to become so anaerobic or ‘sour’ that its use will kill plants

almost instantly241, however by the time it reaches this stage its odour is so

objectionable that it can be easily identified at sour and no-one would want to go

near enough to it to use it).

4.5 TECHNICAL FEASIBILITY OF COMPOSTING BASED ON EXPERIMENTS Two demonstration compost bin systems are on display at the Montserrat National

Trust, one containing brush and manure compost, another containing compost made

of weeds only. In addition, the Botanical Gardens manager, Mappie (Philemon

Murraine) has constructed two compost pits using the traditional Montserratian

method of composting. Each of these compost demonstration units was tested at some

stage, to determine its operating temperature and dissolved oxygen levels. A Solvita

test to determine compost maturity was carried out on each of the compost bins/pits.

Moisture content of the brush and manure compost and compost from the first

demonstration pit was also determined. Finally, a self-heating test was carried out on

the brush and manure compost and also on the compost from one of the pits.

Temperature and dissolved oxygen were measured using a temperature meter and

voltmeter. Moisture content was difficult to determine without using some kind of

oven to dry out the compost. The compost was simply left to dry, relying on the

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naturally high evaporation rates to remove the moisture. Hence any result from the

moisture content test may under-represent the true moisture content of the material.

The self-heating test was carried out using a thermos flask of 2 litre capacity instead

of a Dewar flask as no Dewar flasks are available on Montserrat and none could be

imported in time for the measurements to be taken. The compost moisture content was

adjusted, and it was placed inside the thermos flask with a thermocouple connected to

the temperature meter. The top of the flask was left open to the atmosphere.

Temperature was logged periodically (subject to the demands of other work) and the

temperature meter’s maximum temperature reached was recorded after several days

when it became apparent that the temperature was no longer going to rise.

Solvita tests were carried out on a number of different samples of compost to

determine the degree of maturity. The Solvita test measures carbon-dioxide

respiration and ammonia content. When a compost is mature it is resistant to further

decomposition and does not contain phytotoxic substances such as ammonia and

organic acids242.

The Solvita test is performed by filling the special-purpose jars up to the line marked

on the label. The Solvita test paddles are then placed in the sealed jar and left for four

hours. After four hours, the colour of the gel-paddles is compared with the colour key

supplied with the kit243.

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Figure 4.5 At the beginning of the Solvita test, the jar is filled with compost up to the indicator line and

two gel-coated indicator paddles are added.

Figure 4.6 Indicator used to determine the ammonia evolution from the compost during the test period.

Figure 4.7 Indicator used to determine the CO2 evolution from the compost during the test period.

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Figure 4.8 After four hours, the paddles change colour as a result of a chemical reaction between the NH3 and CO2 gases and the coloured gel indicator. The NH3 and CO2 ratings can thus be determined by comparing the paddles with the indicator colour chart.

Figure 4.9 The moisture content test was carried out by sieving and weighing a 50g sample of compost, setting it aside to allow water to evaporate, and weighing it again after several days had elapsed. No suitable oven was available for accelerated drying.

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Figure 4.10 Five attempts were made to calibrate the dissolved oxygen meter correctly, however due to the lack of bottles of a suitable size in Montserrat it was necessary to cut the plastic bottle used, which

left the dissolved oxygen probe open to the atmosphere.

Figure 4.11 The self-heating test was carried out using a thermos flask as no Dewar flask was available on Montserrat. Temperature was logged at periodic intervals and the maximum temperature was recorded

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The brush and manure compost Solvita test was carried out on 02/07/01, when the

compost was approximately 11 weeks old. The NH3 rating was found to be 5 and the

CO2 rating was 3, giving a compost maturity index of 3. This indicates that possibly

the C:N ratio is too high or the compost is too acidic. Acidic compost is of concern, as

Montserrat’s volcanic soils are already acidic. A Solvita result of 3 indicates an

“active compost”, with “fresh ingredients, still needs intensive oversight and

management” 244. This is usually associated with a stage of III for the Dewar self-

heating test. Material in this class is comparable to dehydrated manures, and is

suitable for landspreading on fallow soil or farm-row crops and field cultivation, or

hothouse beds and greenhouses.

The Solvita test on the weed compost was also carried out on 02/07/01, when the

compost was approximately 11 weeks old. The NH3 rating was found to be 5 and the

CO2 rating was 6, giving a compost maturity index of 6. This indicates a mature

compost. A Solvita result of 6 indicates an “active compost”, “curing ; aeration

requirement reduced; compost ready for piling; significantly reduced management

requirements” 245. Material in this class is comparable to compost-soil blends. It is

suitable for orchards, vineyards and hay crops, or topsoil substitute blends, or general

gardening and top-dressing turf.

For the first compost pit, the Solvita test was carried out on 05/07/01, when the

compost was approximately 7 weeks old. The NH3 rating was found to be 5 and the

CO2 rating was 6, giving a compost maturity index of 6. This indicates a mature

compost, as described above for the weed compost.

After approximately 5 weeks, the second compost pit had an NH3 rating of 5 and the

CO2 rating was 5 also, giving a compost maturity index of 5. This indicates an ideal

curing compost. A Solvita result of 5 indicates an “active compost”, a “compost is

moving past the active phase of decomposition and ready for curing; reduced need for

intensive handling” 246. Material in this class is comparable to organic fertilisers, and

is suitable for farm-row crops and field cultivation, or hothouse beds and greenhouses,

or orchards, vineyards and hay crops, or topsoil substitute blends.

88

The compost pH was not measured in this series of experiments. If the compost pH is

measured then it is possible to estimate the C:N ratio using the results from the

Solvita ammonia colour test.

The moisture content of the brush and manure compost was found to be 30%, and that

of the compost from the pit was found to be 38%. The self heating test on the brush

and manure compost gave a maximum temperature of 31.2°C, reached after 5 days.

For the pit compost, the maximum temperature for the self-heating test was 35.5°C,

probably reached after 2 days. The temperatures recorded during the self-heating tests

for both the brush and manure compost and the pit compost are illustrated below:

Self Heating Test - Brush and Manure Compost

20222426283032

01/0

7/01

01/0

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Date and time (h)

Tem

per

atu

re (

oC

)

Figure 4.12 Temperatures recorded during the self-heating test on the brush and manure compost.

Self Heating Test - Pit Compost

202224262830323436

07/0

7/01

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atu

re (

oC

)

Figure 4.13 Temperatures recorded during the self-heating test on the pit compost.

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180 Dickson, Nancy, Richard, Thomas and Kozlowski, Robert, Composting to Reduce the Waste Stream, Northeast Regional Agricultural and Engineering Service, Ithaca, New York, 1991. 181 URL: http://www.weblife.org/humanure/chapter3_5.html The Humanure Handbook Chapter 3 Gomer the Pile 182 URL: http://www.weblife.org/humanure/chapter3_6.html The Humanure Handbook Chapter 3 Four Necessities for Good Compost. 183 Bannochie, Iris and Light, Marilyn, Gardening in the Caribbean, London, Macmillan Caribbean, 1993. 184 Webster, Aimee, Caribbean Gardening and Flower Arranging, London, Spottiswoode, Ballantyne and Co., 1965. 185 URL: http://www.montserratreporter.org/fra0701-2.htm The Montserrat Reporter 13th July 2001. 186 Dougherty, Mark, Field Guide to On-Farm Composting, Ithaca, New York, Natural Resource Agriculture and Engineering Service, 1999, page 26. 187 Bannochie, Iris and Light, Marilyn, Gardening in the Caribbean, London, Macmillan Caribbean, 1993. 188 Dougherty, Mark, Field Guide to On-Farm Composting, Ithaca, New York, Natural Resource Agriculture and Engineering Service, 1999, page 27. 189 URL: http://www.ag.ohio-state.edu/~ohioline/b792/b792_4.html Ohio State University - The Composting Process- Is Control of pH and Moisture Important During Composting? 190 Dickson, Nancy, Richard, Thomas and Kozlowski, Robert, Composting to Reduce the Waste Stream, Northeast Regional Agricultural and Engineering Service, Ithaca, New York, 1991. 191 Dougherty, Mark, Field Guide to On-Farm Composting, Ithaca, New York, Natural Resource Agriculture and Engineering Service, 1999, page 27. 192 URL: http://www.weblife.org/humanure/chapter3_5.html The Humanure Handbook Chapter 3 Gomer – The Pile. 193 The Wildlife Trusts, Mucking In …The Community Composting Pack, Henry Doubleday Research Association, Lincoln, 1997. 194 Wei, Yuan-Song, Fan, Yao-Bo, Wang, Min-Jian, and Wang, Ju-Si, Composting and Compost Application in China, Resources Conservation and Recycling Vol. 30, pp 277-300,2000. 195 URL: http://navigation.helper.realnames.com/framer/1/0/default.asp?realname=EPA+Office+of+Solid+Waste&url=http%3A%2F%2Fwww%2Eepa%2Egov%2Fosw&frameid=1&providerid=0&uid=10264099 USEPA Process Design Manual Land Application of Sewage Sludge and Domestic Septage 196 URL: http://muextension.missouri.edu/xplor/envqual/wq0424.htm WQ424 Biosolids Standards for Pathogens and Vectors. 197 Dougherty, Mark, Field Guide to On-Farm Composting, Ithaca, New York, Natural Resource Agriculture and Engineering Service, 1999, page 32. 198 URL: http://www.weblife.org/humanure/chapter3_10.html The Humanure Handbook Chapter 3 Compost Biodiversity 199 URL: http://www.weblife.org/humanure/chapter3_10.html The Humanure Handbook Chapter 3 Compost Biodiversity 200 Meekings, Helen J, The Inactivation of Ascarid Eggs in Composting Processes, Leeds, Departments of Civil Engineering and Pure and Applied Biology, 1995. 201 Bannochie, Iris and Light, Marilyn, Gardening in the Caribbean, London, Macmillan Caribbean, 1993. 202 Warren Spring Consultancy, Shanks and McEwan (Energy Services) Ltd, and David Border Composting Consultancy, The Technical Aspects of Controlled Waste Management Markets and Quality Requirements for Composts and Digestates for the Organic Fraction of Household Wastes, Report No. CWM 147/96, Department of the Environment, December 1996. 203 Warren Spring Consultancy, Shanks and McEwan (Energy Services) Ltd, and David Border Composting Consultancy, The Technical Aspects of Controlled Waste Management Markets and Quality Requirements for Composts and Digestates for the Organic Fraction of Household Wastes, Report No. CWM 147/96, Department of the Environment, December 1996. 204 Logsdon, 1990b, 1993, Hoitink et al, 1993, Tilston et al, 1996, cited in Warren Spring Consultancy, Shanks and McEwan (Energy Services) Ltd, and David Border Composting Consultancy, The Technical Aspects of Controlled Waste Management Markets and Quality Requirements for Composts

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and Digestates for the Organic Fraction of Household Wastes, Report No. CWM 147/96, Department of the Environment, December 1996. 205 Logsdon, 1993, cited in Warren Spring Consultancy, Shanks and McEwan (Energy Services) Ltd, and David Border Composting Consultancy, The Technical Aspects of Controlled Waste Management Markets and Quality Requirements for Composts and Digestates for the Organic Fraction of Household Wastes, Report No. CWM 147/96, Department of the Environment, December 1996. 206 Hoitink et al, 1993, cited in Warren Spring Consultancy, Shanks and McEwan (Energy Services) Ltd, and David Border Composting Consultancy, The Technical Aspects of Controlled Waste Management Markets and Quality Requirements for Composts and Digestates for the Organic Fraction of Household Wastes, Report No. CWM 147/96, Department of the Environment, December 1996. 207 Tilston et al, 1996, cited in Warren Spring Consultancy, Shanks and McEwan (Energy Services) Ltd, and David Border Composting Consultancy, The Technical Aspects of Controlled Waste Management Markets and Quality Requirements for Composts and Digestates for the Organic Fraction of Household Wastes, Report No. CWM 147/96, Department of the Environment, December 1996. 208 URL: http://www.weblife.org/humanure/chapter3_2.html The Humanure Handbook Chapter 3 Compost Defined. 209 URL: http://www.weblife.org/humanure/chapter3_12.html Humanure Handbook, Chapter 3, Compost Miracles 210 URL: http://www.btny.purdue.edu/Extension/Pathology/CropDiseases/Corn/corn2.html#anthracnosestalkrot Crop Diseases in Corn 211 Hoitink, H.A.J., Chen, W., Trillas-Gay, M.I. and Chung, Y.R., Compost for Control of Plant Diseases, in de Bertoldi, M. Ferranti, M.P., L’Hermite, P. and Zucconi, F. (eds), Compost: Production, Quality and Use, London, Elsevier Applied Science, 1987. 212 Warren Spring Consultancy, Shanks and McEwan (Energy Services) Ltd, and David Border Composting Consultancy, The Technical Aspects of Controlled Waste Management Markets and Quality Requirements for Composts and Digestates for the Organic Fraction of Household Wastes, Report No. CWM 147/96, Department of the Environment, December 1996. 213 URL: http://www.epa.gov/compost/disease.pdf Innovative uses of compost disease control for plants and animals 214 Dougherty, Mark, Field Guide to On-Farm Composting, Ithaca, New York, Natural Resource Agriculture and Engineering Service, 1999, page 90. 215 URL: http://www.weblife.org/humanure/chapter3_12.html Humanure Handbook, Chapter 3, Compost Miracles 216 Island Resources Foundation and Montserrat National Trust, Montserrat Environmental Profile, 1993. 217 Marafa, L.M., Chau, K.C., Effect of Hill Fire on Upland Soil in Hong Kong, Forestry Ecology and Management, vol 120, no. 1-3, pp 97-104, 5 May 1999. 218 Kutiel, P and Inbar, M, Fire Impacts on Soil Nutrients and Soil Erosion in a Mediterranean Pine Forest Plantation, Catena, Vol. 20, No. ½, p. 129-139, February/April 1993. 219 Villar, M.C. botulinum, Gonzalez-Prieto, SJ, and Carballas, T, Evaluation of Three Organic Wastes for Reclaiming Burnt Soils: Improvement in the Recovery of Vegetation Cover and Soil Fertility in Pot Experiments, Biology and Fertility of Soils, vol. 26, no. 2, pp. 122-129, 1997. 220 Deka, HK and Mishra, RR, The Effect of Slash Burning on Soil Microflora, Plant and Soil, vol. 73, no.2, pp 167-175, 1983. 221 Montserrat Statistics Office, personal communication, 2001. 222 Warren Spring Consultancy, Shanks and McEwan (Energy Services) Ltd, and David Border Composting Consultancy, The Technical Aspects of Controlled Waste Management Markets and Quality Requirements for Composts and Digestates for the Organic Fraction of Household Wastes, Report No. CWM 147/96, Department of the Environment, December 1996. 223 URL: http://www.weblife.org/humanure/chapter3_11.html Humanure Handbook. Chapter 3: Compost Myths 224 Montserrat Statistics Office, personal communication, 2001. 225 Howard, Sir Albert, An Agricultural Testament, New York, Oxford University Press, 1943.cited in URL: http://www.weblife.org/humanure/chapter3_4.html Humanure Handbook, Chapter 3, Solar Power in a Banana Peel. 226 Warren Spring Consultancy, Shanks and McEwan (Energy Services) Ltd, and David Border Composting Consultancy, The Technical Aspects of Controlled Waste Management Markets and

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Quality Requirements for Composts and Digestates for the Organic Fraction of Household Wastes, Report No. CWM 147/96, Department of the Environment, December 1996. 227 URL: http://www.weblife.org/humanure/chapter3_11.html The Humanure Handbook – Chapter 3 Compost Myths 228 Kendle, 1996, cited in Warren Spring Consultancy, Shanks and McEwan (Energy Services) Ltd, and David Border Composting Consultancy, The Technical Aspects of Controlled Waste Management Markets and Quality Requirements for Composts and Digestates for the Organic Fraction of Household Wastes, Report No. CWM 147/96, Department of the Environment, December 1996. 229 Lang, D.M., Soil and Land Use Surveys, No. 22 – Montserrat, March 1967, University of the West Indies, Trinidad, 1967. 230 Bannochie, Iris and Light, Marilyn, Gardening in the Caribbean, London, Macmillan Caribbean, 1993. 231 Kendle, 1996, ibid. cited in Warren Spring Consultancy, Shanks and McEwan (Energy Services) Ltd, and David Border Composting Consultancy, The Technical Aspects of Controlled Waste Management Markets and Quality Requirements for Composts and Digestates for the Organic Fraction of Household Wastes, Report No. CWM 147/96, Department of the Environment, December 1996. 232 Levington Agriculture Ltd and Rainbow Wilson Associates, An Assessment of the Quality of Waste Derived Composts Produced by a Range of Processes, Technical Report No. P229, Bristol, Environment Agency, 2000. 233 Dunn, Roger, Nortcliff, Steve, Baker, R. Martin, Kendle, Tony, Pickering, Jon and Hadley, Paul, The Technical Aspects of Controlled Waste Management – Horticultural and Landscape Use of Municipal and Green Waste Compost, Report No. CWM/124/94, Wastes Technical Division, Environment Agency, 1994. 234 MAFF, 1994, cited in Warren Spring Laboratory, Shanks and McEwan (Energy Services) Ltd and David Border Composting Consultancy, The Technical Aspects of Controlled Waste Management Markets and Quality requirements for Composts and Digestates from the Organic Fraction of Household Wastes. Report No. CWM 147/96, Department of the Environment, December 1996. 235 URL: http://www.boldweb.com/greenweb/compost.htm Using your finished compost 236 URL: http://www.boldweb.com/greenweb/compost.htm Using your finished compost 237 URL: http://www.boldweb.com/greenweb/compost.htm Using your finished compost 238 Dougherty, Mark, Field Guide to On-Farm Composting, Ithaca, New York, Natural Resource Agriculture and Engineering Service, 1999, page 91. 239 Henchie, Stewart, personal communication, 2001. 240 Dougherty, Mark, Field Guide to On-Farm Composting, Ithaca, New York, Natural Resource Agriculture and Engineering Service, 1999, page 32. 241 Dougherty, Mark, Field Guide to On-Farm Composting, Ithaca, New York, Natural Resource Agriculture and Engineering Service, 1999, page 85. 242 URL: http://www.woodsend.org/solvita.htm Solvita Compost Maturity Test 243 URL: http://www.woodsend.org/solvita.htm Solvita Compost Maturity Test 244 URL: http://www.woodsend.org/manual.htm Guide to Solvita Testing for Compost Maturity Index 245 URL: http://www.woodsend.org/manual.htm Guide to Solvita Testing for Compost Maturity Index 246 URL: http://www.woodsend.org/manual.htm Guide to Solvita Testing for Compost Maturity Index