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Earth
Air Fire and Water Introduction. 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 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
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 Light Intensity and Duration 2.4 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
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 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 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
Table 2.7A will enable you to arrive at a reasonable estimate of flowering times for your area.
Harvesting for Quality 2.8 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 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 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 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 Harvesting the Seed 2.13 Harvesting the Bark 2.14 Harvesting of non standard parts 2.15 Post Harvest Procedures 2.16 Post Harvest Procedures. The Root 2.17 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 Insect damage. Insect eggs or infestation. Bird excreta.
Disease or fungal infection. Tissue damage. Post Harvest Procedures. The Whole Herb 2.19 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 Post Harvest Procedures. General Points 2.21 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 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 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
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 metre� of drying surface required. 816 metre� � by 7 days = 116.57 metre� of drying surface to be provided on a daily basis, to dehydrate the crop. Library
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