Earth Air Fire and Water
The Pharmageddon Herbal
Chapter 2.
Introduction.
The harvest is now a measure of economic productivity, Lines of hieroglyphs that tell a story for the taxman. Pity those that get caught on the banker or chemical company treadmill. For they cannot see the natural alchemy of which they are a part. Our kind has been fecund. It may have been that very fecundity that finally forced the greater part of the nomads into settled lifestyles, and the shaman to change his face, as the Earth moves around the Sun.
The new born agriculture was a momentous leap of intellectual vigour, stimulated by survival instinct. So much to be done. Calendars to be constructed, Pyramids, Ziggurats and Henge’s to be erected, great terraces and earthworks cut. Vast stone instruments, to predict the passage of the chariots of the Gods. Even more intriguing, portable moon calendars carved in bone, and star maps imaged with shells, on a wooden lattice. They knew the world was round. A roundness of cycles into infinity.
No settled community is possible without a calendar to mark out the progression of the seasons. Harvest home was always a time of festivity and feasting, and always sanctified by tribute to the ruling Deity. The people knew that they would survive until the saving onset of Spring. Because they were so close to Nature, they understood that they were dependent, on forces beyond their control. Nothing has changed. A loaded trolley at the supermarket. Nothing has changed. We are still dependent on forces beyond our control. Even the most powerful must kneel. They may be last to kneel, but kneel they must.
Spring is born from the metamorphosis of Autumn and Winter. Autumn is born of the metamorphosis of Spring and Summer. Endless seasons spinning out like a line from the Zodiac spool.
Harvesting and Dehydration Schedules 2.1
Harvesting is carried out when a crop is at peak condition for the purpose of which it is required and as such it is usually a straight forward operation. However herb growers must work within the parameters set by their processing capacity. The capacity is set by the ability to dry and stabilise the crops when they are in peak condition.
Under capacity will result in considerable loss, therefore to avoid complications careful planning is necessary. To determine the dehydration capacity required the grower must set the area to be cultivated and estimate the probable yields of the herbs to be planted. This may be calculated from the data given in part 2. The grower must then know the approximate flowering times of the herbs in order to allocate dehydration time as each specie comes on stream. There are a number of variables that affect the flowering times for different plants.
Climatic Factors 2.2
Climate is the weather pattern for a specific location that will repeat itself season after season. The climate is composed of the following variables;
Temperature range.
Rainfall, the amount and frequency.
The level of humidity.
The duration and intensity of light.
Wind speed and direction.
The variables given are determined in their turn by the following;
Latitude. Longitude.
Altitude. Proximity to the coast
Overall land mass. Natural vegetation.
It is possible within reason to create micro-climates by means of technology or naturally by employing Perma-Culture techniques. (Bill Mollison)
Temperature 2.3
The temperature determines the rate of chemical reaction within living protoplasm. Many herbs of commerce are able to cope with a widely fluctuating range of temperatures. Specific temperature requirements will vary markedly under different growing conditions such as rainfall and duration and intensity of light.
Light Intensity and Duration 2.4
The amount and intensity of light available to a plant is determined by latitude that is then modified by season, cloud cover, atmospheric pollution and the time of day. Most herbs of commerce require a medium to high light intensity.
Light duration or day length varies according to latitude. Table 2.4A indicates day length at various latitudes North and South of the equator.
Table 2.4A
Latitude |
Day length |
Effect |
0° |
12 Hours |
Short day, long growing period |
5° |
11.6 to 12.2 |
Short day, long growing period |
10° |
11.3 to 12.5 |
Short day, long growing period |
15° |
11.0 to 12.8 |
Short day, long growing period |
20° |
10.7 to 13.1 |
Short day, long growing period |
25° |
10.3 to 13.4 |
Short day, long growing period |
30° |
9.9 to 13.8 |
Short day, long growing period |
35° |
9.5 to 14.2 |
Long day, short growing period |
40° |
9.0 to 14.7 |
Long day, short growing period |
Many plants are so sensitive to day length that they may be induced to flower by manipulating the hours of light and dark to which they are exposed. This phenomenon is called photoperiodism.
Therefore plants may be classified according to their reaction ie. Day Neutral, Day Short or Day Long. In fact it is the hours of darkness that are critical for the flowering of short or day long plants.
Water Requirements 2.5
As a rule of thumb herbs will need less water than vegetable crops and usually exhibit good resistance to drought conditions, however to realise their potential, they will need water at regular intervals.
In areas of uncertain rainfall during the growing season it may be necessary to resort to irrigation. In such cases the grower should be prepared to deliver an average of 18mm of water per fortnight. That is equivalent to 180,000 litres or 180 cubic metres per hectare. That equates to 16,023 imperial gallons or 19,242 U.S. gallons per acre.
The amount of water actually delivered must be based on the growers own judgement. The herbs should be given water when seen to be necessary, ie at planting and thereafter to maintain growth. Irrigation once commenced should be continued at regular intervals unless rain intervenes. Herbs as a rule require far less water than our food crops.
The amount of water given should be tapered off around 4 to 5 weeks before harvest; this conditions the herb and promotes favourable dehydration.
The most water critical period is within 3 weeks of planting. Undue water stress during that time will give rise to weak and stunted plants.
Wind Shelter 2.6
Wind speeds high enough to cause visible physical damage are the exception rather than the rule. Moderate prevailing winds are equally damaging but much more insidious, culminating in a significant loss of yield due to stunting of growth.
Prevailing winds lower the ambient temperature and humidity levels which in turn facilitates the stripping of moisture from the soil and plant. The immediate effect is wind chill; the evaporation of moisture causes a quick drop in the temperature of the plant and surrounding soil, which if prolonged, will lead to water stress. These sudden fluctuations are not conducive to the thrift and health of the plant therefore wind shelter should be considered mandatory.
Latitude, Longitude and Altitude 2.7
Taken individually or in combination, latitude, longitude and altitude have a direct bearing on climate, and as such, strongly influence flowering times.
1° (degree) of latitude equals 109 km approximately.
1° (degree) of longitude equals 111 km approximately.
The equator is 0° of latitude.
For each degree of latitude North or South of the equator, flowering is retarded by 4 days.
From East to West each 5° of longitude will advance flowering by 4 days
For each rise of 125 metres above sea level flowering will be retarded by 4 days.
Table 2.7A will enable you to arrive at a reasonable estimate of flowering times for your area.
Harvesting for Quality 2.8
Over the past few decades many of the plants, which are of commercial importance to the pharmaceutical and flavouring industries, have undergone scientific scrutiny to determine optimal harvesting times for particular end use requirements.
Predictably investigations have confirmed that the levels and composition of secondary metabolites are subject to seasonal variations of climate, nutrients and the maturity of the plant. It is reassuring to note that the scientific findings validate many centuries of empirical knowledge.
It may be seen in table 2.7A that considerable latitude is shown for the harvesting of the species listed. This is accounted for by the plant part required, and also the habit of the regrowth displayed by plants harvested for shoots or flowering tops, where 2 or 3 cuts may be taken in a season.
Harvesting the Root 2.9
Autumn and early spring are the times designated for the harvesting of medicinal roots. By early or late autumn most herbs will have completed their seasonal cycle and against a background of falling air and soil temperatures the root commences to transfer residual materials from leaf and stem. The materials are stored by the root and then used to fuel spring growth.
As the transfer proceeds the aerial part of the plant commences to die back. When the die back is complete the metabolism slows down and the root enters a dormant phase. Roots specified for autumn collection are harvested at the end of the second season, that allows the root or tuber to properly develop.
Roots designated for spring harvest are dug at the commencement of the third season. Unless a buyer specifies otherwise the root must be dug before it breaks dormancy otherwise the ensuing enzyme activity will materially alter the composition and levels of the secondary metabolites.
Harvesting the Leaf 2.10
Leaf only drug plants are usually alkaloid or glycoside producers with a potent and potentially lethal effect on heart, lungs or central nervous system. They are listed in most National Poison Schedules and hedged about by restrictions. Before cultivating such plants it would be prudent to consult with the appropriate authorities.
Most national pharmacopoeias and dispensatories contain detailed monographs of such plants and will usually specify the collection time. The individual leaves are collected by hand at their maximum point of growth. That point may be taken as the first indication of bud form. Buds and flowers are modified leaves, when the first modification is noted, harvesting should commence. The leaves should be collected when the dew has dried and taken from the bottom up, ignoring any damaged basal or immature leaves.
Individual leaves are laid flat on trays or baskets. Care must be taken to ensure that ferment heating does not occur.
Harvesting the Whole Herb above ground 2.11
The harvesting of whole herb is the rule rather than the exception for extraction purposes. The required metabolites are generally distributed throughout the plant. In line with the timing for leaves, the herb is taken just on bud break at it’s maximum point of growth.
There are some few exceptions, i.e. Atropa belladonna is sometimes harvested when in first fruit, or Henbane and Thorn Apple, which are harvested when in flower. Such variations are usually the subject of monographs in a pharmacopoeia.
Plants should be cut just above the woody part of the stem. Upon harvesting the herb should be quickly transported to the processing area so that undue chemical changes are avoided. Large quantities of fresh cut herb bruise and sweat easily and will speedily succumb to ferment heating.
Harvesting the Flower 2.12
The harvesting of flowers should commence on a dry day when the dew has dried. The flower should be picked when fully open but not blown. Damaged or blown blooms should be discarded. Most flower petals are 90% water, very delicate and easily bruised, such damage results in oxidation and ferment problems causing discolouration and loss of volatile principles. If petals only are required it will be more convenient and result in less damage if the petals are removed from the calyx after they have undergone drying.
Harvesting the Seed 2.13
Harvesting the of seed crops closely follows that of the food grain crops. The herb is cut when the seed is just on ripe i.e. at the first colour change from green. The herb is bundled and arranged in shocks and allowed to sun dry and ripen. It is then threshed and winnowed.
Harvesting the Bark 2.14
Bark is usually harvested in the spring when the sap-run is fresh and strong. It is detrimental to the health of a tree to remove bark from the trunk. The best procedure is to remove a suitably sized branch and strip the bark from that. Take care to paint the wound on the tree with a preparation of a natural resin or wax to seal out pathogens. Take the branch from the tree sun side. Sunlight inhibits fungal growth.
Harvesting of non standard parts 2.15
Certain types of herbal preparations require that they be manufactured from the whole plant at a specific stage of growth e.g. root, leaf and flower, in which case the whole plant should be harvested in line with the directions given in Para 2.12. If the requirements are for root, leaf and fruit, then the herb should be harvested when the berries are just on ripe.
Post Harvest Procedures 2.16
At the point of harvest far reaching changes are set in motion; the living herb starts to die. Bio-chemical reactions such as autolysis commence. The cellular breakdown is closely followed by invasion of micro-organisms. This intense chemical activity unless checked will render the herbal material useless for medical purposes, or as is more usual, the potency and efficiency of the herb is badly compromised. Therefore post harvest procedures must be swift and efficient. Enzyme activity can only occur in the presence of water, the sooner the material is subjected to the drying process the better. There are some exceptions to this general rule, those exceptions in the main are comprised of beverages and flavourings such as tea, cocoa beans, vanilla pods; or industrial ware such as woad; perfumery items like orris and the recreational drug nicotine. The two major exceptions for materials that are used medicinally are lavender and gentian root.
Post Harvest Procedures. The Root 2.17
Medicinal roots are harvested in the same manner as that applied to the food root crops. Care should be taken to ensure that the roots are not unduly bruised or damaged in the process. The root once dug must be separated form the soil and other adhering matter. The method used will depend upon soil type.
Light sandy soils can usually be removed by light brushing or agitation and sifting whereas heavier soils will need to be removed by the mechanical action of water. Modern methods involve the use of revolving drums and high pressure water sprays. Traditional methods included immersion in water troughs prior to brushing and rinsing or the roots were packed into sacks and suspended in a running creek or steam.
Once the root is clean hair roots and damaged parts must be trimmed off and any diseased or wormy roots disposed of. If the end use requires that the root be scraped then it should be done at this stage. With a few exception, whole roots are rarely encountered in commerce. The reasons are technically based; whole roots are notoriously difficult to dry in a satisfactory manner; they require a long and therefore deleterious drying time producing unwanted bio-chemical reactions which are accelerated by mechanical reactions such as root splitting and case hardening. Those problems may be eliminated by chopping, slicing or dicing the root prior to dehydration. The loading trays should be held ready for use and then moved to the dehydrator with all possible speed.
Post Harvest Procedures. The Leaf 2.18
Leaves must be carefully examined for the following;
Insect damage. Insect eggs or infestation. Bird excreta. Disease or fungal infection. Tissue damage.
Damaged or contaminated leaves should be discarded. The undersides of bottom leaves may be flecked with mud, splatter from heavy rain. Do not attempt to clean the leaves while they are in the fresh state, dry the leaves first and the mud may be easily removed by sieving. Leaves for drying should be threaded on string or thin rods. If they are to be dried on trays then they should be laid flat in a single layer, otherwise blackening will occur during the process.
Post Harvest Procedures. The Whole Herb 2.19
Each plant should be examined for damage or contamination as listed in Para 2.18. Any damaged material should be removed from the plant and disposed of. The initial inspection must be thorough, damaged material will considerably lower the crop value, whilst insect eggs can lead to infestation problems during storage
When the crop has been cleaned it should be cut or chopped into 2.5cm pieces. This ensures easy tray loading and even drying and the simplification of subsequent processing procedures. The drying trays may be loaded to a depth of 5cm.
Post Harvest Procedures. The Flower 2.20
Flowers should be scrutinised for insects, caterpillars and eggs. If this procedure is skimped then infestation during storage is the inevitable result. Rose and Calendula flowers being particularly prone. It is always best to remove petals from the Calyx after dehydration. This may be done by rubbing and sifting the material across a suitable screen.
Post Harvest Procedures. General Points 2.21
Observation will demonstrate that the herbs cycle of growth is closely related to the lunar cycle, and that the major biological surges occur on or around the full moon. The full moon is used as a harvesting marker. For reasons both economic, and scale of operation, it is not practical to process a complete crop in one dehydration run. Therefore the grower must accept a quality trade off in order to extend the harvesting period.
A good quality crop may be obtained by working to a seven day cycle, i.e. harvesting may commence 3 days before a full moon and terminate 3 days after. Obviously such considerations do not apply to root crops which are harvested in the dormant phase.
Provision of Drying Surface 2.22
A major factor affecting dehydration capacity is the area and type of drying surface available. Fixed drying surfaces such as shelves or racks are a serious drain on time and labour and add considerably to damage and leaf shatter when a crop is handled. The use of portable drying trays will eliminate the problems. A 1 metre x 1 metre tray allows for speedy manipulation at the load and unload points. If it becomes necessary to turn the herb to dry wet spots then that may be done by placing an empty tray on top of a loaded one and then turning the trays over. The savings in labour unit hours across one season are considerable.
A 1 metre x 1 metre drying tray will hold on average;
Chopped Herb – 2 to 3 kg. Chopped Root – 3 to 4 kg. Flowers or Petals – 0.5 to1.5 kg.
With experience, an operator can accurately load by sight and compensate for dehydrator quirks.
The Dehydration Schedule 2.23
The growers dehydration capacity must bear some relationship to the area under cultivation if economic loss is to be avoided. That relationship may be determined by compiling a dehydration schedule. As a planning tool it will allow the grower to forecast the following information.
When the dehydrator is in use and for how long. Peak loading times and potential bottlenecks. The amount of drying surface required for the crop.
Once the type of crop and size of cultivation has been decided then the schedule should be compiled. The schedule can be designed to yield greater or lesser data according to need.
The following example table is based on a 1 hectare cultivation laid out to 5 species on an equal land basis, ie 2000m2 per specie.
Table 2.23A
Key to columns |
Data source |
Key to column A |
[A] Plant part required |
Table 2.7A |
[2] Whole Herb |
[B] Fresh yield 2000m² |
Extrapolated Table 1.2B |
[3] Root |
[C] Drying surface as m² |
Extrapolated Para 2.22 |
[4] Flower |
[D] Drying ratio |
Table 1.2A |
*** |
[E] Dry yield |
Table 1.2B |
*** |
N.B. It may be seen from the table that there are overlaps in the harvesting periods, with peak demand in mid summer. The amount of drying surface required is divided across a 7 day period with two or three dehydration runs per 24 hours.
For example let us take the data shown in the table, as it relates to Lemon Balm.
Column A. Whole Herb.
Column B. Fresh Yield. …………….. 2040 Kg.
From Para 2.22 it will be seen that a 1 x 1 metre drying tray will hold between 2 and 3 Kg. Average 2.5 Kg.
Therefore 2040 Kg ÷ by 2.5 Kg = 816 metre² of drying surface required.
816 metre² ÷ by 7 days = 116.57 metre² of drying surface to be provided on a daily basis, to dehydrate the crop.
Library
Pharmageddon Herbal Block Index
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