Free From School Part 5

I hope when they read this book they will forgive me for all the trouble I must have caused them.

Extracts from Diary: Earthworms

10th November: Sir gave me a book on earthworms to read, then Jagan took me down to the field. There I was able to observe many organisms other than earthworms. We took a soil sample from one place and then went back to the lab where we put the soil sample into the tulgren funnel. I then went and brought three more samples from the vermi-tech pit. We then put these also into three other tulgren funnels. By then it was lunch time and we all ate together. After lunch I weighed the soil samples and got to see the organisms that were in the beaker under the tulgren funnel. At 3.30 p.m I left for home.

11th November: In the morning, I was given two types of earthworms i.e.

Lampito mauritii and Perionyx excavatus and told to observe them. I spent the whole morning doing this. After lunch, I wrote down the observations that I had made. In the evening we went out to the College playground and also to the area near the College Boarding to make some observations. We dug two pits of 25 cm x 25 cm x 25 cm each at the playground and one, of the same size, at the Boarding. We made many observations which included the number and species of earthworms we found and whether they were c.l.i.tellates or not. We also made observations regarding soil, atmospheric temperature and relative humidity and took soil samples to measure the moisture content.

12th November: Left for New College as usual. I was told that Sir did not come today as he had a high viral fever. Yesterday a research scholar had expired and so there was a condolence meeting today. After that everybody left as it was declared a holiday. I arrived home at about 10.30 a.m. I had a bath and then some food. I then watched a bit of TV and wrote my diary. In the night Uncle Mano and Aunty Sagu had invited some guests and had cooked chicken curry which I enjoyed very much.

14th November: Sir did not arrive today either. With the help of Jagan I used the Infrared Moisture Balance to find out the moisture content of the soil samples which we had taken on Sat.u.r.day. After we finished one sample, the voltage started fluctuating so we used the tulgren funnel instead. Then Jagan sent me to get soil samples from the field and from the area near the Boarding. We put the soil samples in the tulgren funnel and observed the arthropods that fell into the beaker under a compound microscope. We also observed some preserved specimens of microarthropods.

15th November: Pounded 100 gms of soil sample and then sieved each soil sample through 5 sieves. Then weighed the soil in each sieve and noted this down.

16th November: Did sieving of soil in the morning. In the evening, used Keenscups to find out the waterholding capacity/porosity.

18th November: Sir arrived this morning. Read some books in the library for sometime. Then did a bit of soil sieving and then did burning of soil in a bunsen burner. In the afternoon, I watched a very comic film called "Junior Shylock".

19th November: Started preparing my report in rough. In the evening I went with Babu to buy a film roll for taking photographs for my report.

20th November: Did burning of a second sample of soil. After that Jagan, Sir and I photographed microarthropods with the help of the compound microscope that has a camera attached to it. After lunch, I attended a seminar conducted by one of the students.

21st November: Ate a Perionyx excavatus earthworm in the morning. Then weighed some soil samples to find out the waterholding capacity of different soils, weighed burnt soil, also learnt how to calculate and find out soil texture of different samples of soil. Continued writing my report.

22nd November: Sat and wrote the final parts of my report. Then I gave it to Chitra who corrected it. After she finished, she gave it to Sir who also made some corrections.

23rd November: Wrote my report in fair in the new notebook I had bought. Then Jagan and I stuck the photographs we had clicked earlier in the various s.p.a.ces in the notebook. Then Sir said that I would have to prepare a vermi-bed on my own. He gave me a bucket and I made a vermi-bed in it. Sir checked that I had done it correctly.

24th November: Drew some diagrams that remained to be done in my notebook. Then gave it to Sir for final approval. He made me write a few lines about each photograph. He said I should come and collect it after a week or so. After that I said bye to everyone and left at 4.30 for home.

10 days later...

5th December: Today was a holiday, so I went to collect my report book from New College where I had given it to Sir for his signing. Met all my friends there. All of them wrote their remarks in my report book and then it was stamped. Sir gave me a certificate for the earthworm course I had finished at the Inst.i.tute. Then Chitra dropped me in her Fiat car near the Panagal Park bus stop.

Field Notes on Vermiculture: Turning Garbage into Gold

Vermicompost and vermiwash are the two earthworm products that have become very popular nowadays. Ordinary organic garbage which consists of litter, such as, kitchen waste and dead plant material is used and converted into manure with the help of earthworms.

Earthworms

There are three kinds of earthworms. One, the epigeal or surface earthworm (Perionyx excavatus) which eats only organic litter which is present on the top layer of the soil. Two, the anecic earthworms (Lampito mauritii) which are present in the upper layers of soil and feed on waste and leaf litter. The third kind are present deep inside the soil and are known as endogeic earthworms (Octochaetona thriretonis).

The most suitable earthworms recommended for vermiculture are the epigeic and anecic earthworms. Perionyx excavatus is purplish red and rough. Near the two ends the Perionyx excavatus is almost black in colour. It is smaller and thinner (approx. 10 cms long) and more active compared to the Lampito mauritii. They also breed faster than Lampito mauritii. Lampito mauritii are greyish white in colour and shiny, thicker and longer (length-16 cms) compared to Perionyx excavatus.

Earthworms prefer cool temperatures, moist soil, humidity, relatively less sunlight and neither too coa.r.s.e nor too fine sand. These are the ideal conditions that must be kept in mind when using them for vermiculture. Since earthworms breathe through the skin, they perish if their skin becomes dry or the quant.i.ty of mucus diminishes. Hence to keep earthworms alive in the vermicompost containers, care should be taken to ensure that the vermibed remains moist. Earthworms however do not prefer waterlogged soils. In fact if earthworms are kept in water for too long, the concentration of ammonia that is discharged through their excreta makes the water too toxic for the earthworms to survive.

Earthworms also cannot tolerate salt or salt water even briefly.

Earthworms are hermaphrodites. Depending on the species, their life span is between six months to one year. Fully matured earthworms upon mating shed their c.l.i.tellum (a small band like an overgrowth of skin) and produce coc.o.o.ns which take about 14 days to incubate and hatch into juveniles. Maximum three juveniles are hatched from each coc.o.o.n. From the juvenile to the c.l.i.tellate stage i.e. the fully matured or reproductive stage it takes 15-18 days. Thus earthworms are able to multiply several times in their life span which makes them ideally suited to process even large quant.i.ties of garbage.

Vermicompost

A pit, a small plastic or wooden crate or, even a bucket, can be used for vermicomposting organic matter. Although not necessary, two crates can be used simultaneously; while one is being used for fresh garbage, the garbage in the other can be allowed to decompose.

First, 6-8 holes should be made (one at each corner and four in the middle of the crate). A pot or a bucket needs about 3-5 holes. The crate or pit must first be filled with a one inch layer of pebbles or broken bricks. Then, a half to one inch layer of sand should be spread.

Over that, a five to six inch layer of soil should be spread. Then Lampito mauritii and Perionyx excavatus earthworms should be introduced. The soil must then be moistened with water. A little bit of cowdung (nitrogen) and some hay (carbon) should be spread on it, and the contents of the pit left for 20-30 days. This is called a vermibed.

The cowdung and hay will allow the worms to multiply. With this, the vermicompost crate or pit will be ready for processing organic waste.

All organic waste should be evenly spread out on the vermibed. As far as possible add garbage in small quant.i.ties regularly rather than dumping large quant.i.ties at one go. The earthworm begins processing the garbage immediately. Water the container occasionally so that the vermibed remains moist. Once the container is full with organic waste, it should be covered with a little soil and allowed to decompose undisturbed. Only watering the pit should continue. After it has decomposed fully (roughly 45 days) watering must be stopped for about 3 to 5 days. This will force the earthworms to migrate down to the bottom of the container which will have some moisture as compared with the top soil. Then the top layer of soil which is really the organic matter which has been converted into manure should be removed without disturbing the vermibed. This organic manure can be used for plants.

Vermiwash

A drum, barrel or bucket can be used for making vermiwash. The drum or bucket should be placed on supports a little above the ground. A hole should be made at the bottom of the container. A pipe should be pushed through the hole and a tap attached to the outer end.

The bottom of the drum should be covered with a layer of gravel (about 6-8 inches). Over it, a layer of sand (6-8 inches), and then a layer of soil (6-8 inches) should be spread. The earthworms should then be introduced and the soil moistened a little. Then a little bit of cowdung and hay should be mixed together and scattered over it. This should be left for a few days.

Whenever vermiwash is needed, water should be sprinkled with a shower or, gradually poured on top of it (5 litres of water for a 150 litres drum). The water will pa.s.s through the earthworm burrows and the organically rich soil will become liquid manure and can be collected at the bottom of the container. As the hay and cowdung is eaten up by the earthworms, this should gradually be replaced.

Conclusion

In nature, litter is decomposed in a way similar to what happens in a vermicompost pit. Litter (consisting of leaf material, twigs, bark, dead wood, flowers, fruits and other plant and animal material) that falls on the ground is constantly moistened by dew or rain.

Decomposition then sets in with the help of microbes, fungi and microarthropods.

Microarthropods are of two kinds-the detritivores that feed on the litter attacked by the microbes and fungi and the predators that feed on the detritivores. The litter that has not been decomposed, dead microbes and microarthropods, along with their excretions and secretions, mix and form humus. This humus is in a complex form and therefore not available to the plants for use. Here is where earthworms come into the picture. The earthworms present in the soil feed on the humus. The castings (wormicasts) excreted by these earthworms, as a result, contain nutrients in a form that is readily available to the plants for their growth. The plants in turn, when they die or shed leaves, contribute to the litter which becomes food for microbes and fungi. Thus nature's cycle is made whole and complete.

Earthworms have proven that they are wonderful creatures for they can truly turn garbage into gold.

Chapter 9: Spiders

My stint with vermiculture over, I had another fortnight of study with Dr K. Vijayalakshmi, whom my dad calls India's 'Spider Woman'. Dr Vijayalakshmi has been doing research on rearing spiders as a biological weapon for controlling c.o.c.kroaches and her workplace is full of spiders of various types, all in bottles, and bred under her supervision. An authority on spiders, she is also the author of a well-known book on the subject.

Actually I had been anxiously waiting for a phone call from my parents saying that the decks were cleared for my Crocodile Bank visit. Instead Dad had phoned to say that the final arrangements for my stay at Croc Bank were still being finalised and that I could use the 10 days or so in between to learn what I could from Dr Vijayalakshmi about spiders, and the unusual use she intends to put them to. I had readily agreed.

Dr K. Vijayalakshmi and her husband both work in an organisation called the Centre for Indian Knowledge Systems (CIKS). CIKS is housed in a one storey building and Dr Vijayalakshmi's office is on the first floor.

Here she studies various plants that are useful as pesticides and so on. But I was not at all concerned with that aspect of her work.

In the garage of the building was the Spider Room-a laboratory of sorts filled with bottles of different spiders in various stages of growth.

There must have been over 500 transparent plastic bottles at the time I was there, each one neatly labelled, and all sitting one next to the other with spiders in them. For air, each bottle had tiny pinholes in its lid. Feeding was done through another small hole in the lid: this hole was plugged with cotton. All these spiders and their activities including growth, moulting, mating and hatching of babies were monitored by Dr Vijayalakshmi. She had an a.s.sistant called Selvan and he followed her instructions, keeping the records and making the notings in a log book.

During the fortnight that I worked with Dr Vijayalakshmi, I simply slipped into this set-up, reading books about spiders that Dr Vijayalakshmi gave me, then learning to identify different spiders and simultaneously helping Selvan in all the tasks that were needed to maintain the huge spider population housed in the garage.

The spiders that Dr Vijayalakshmi deals with are called giant crab spiders. These spiders do not build webs. They feed only on c.o.c.kroaches. The spiders were a little smaller than their prey i.e. the c.o.c.kroaches. I used to separate the babies, feed them, check the moultings and catch flies for feeding them. I read a lot of books here and sometimes caught the spiders in the garden in order to identify and study them.

Spiders were not the only creatures housed in the garage. There were also c.o.c.kroaches bred in buckets with rolled cardboard in the centre and broken biscuit pieces thrown in the bucket. The c.o.c.kroaches were fed once a week or so to the giant crab spiders.

The smaller spiders used to get flies to eat and these were caught by us everyday from the garden. The flies have to be fed alive to the spiders, so we used transparent plastic bottles to trap the flies and once caught we would carefully put them into the spider's bottle.

Sometimes the spider would immediately catch the prey and eat it; at other times the fly would buzz around in the bottle for days till the spider was ready to eat it.