Detailed Explanation of Key Technical Points for Large-Scale Earthworm Farming
The earthworm, commonly known as dilong, is a representative animal of the class Oligochaeta in the phylum Annelida. Earthworms mostly live in moist, fertile soil and are saprophytic animals that feed on decaying organic matter. In recent years, more and more farmers have been raising earthworms. Earthworms are rich in protein, amino acids, fats, minerals, vitamins and trace elements, with high nutritional value, and can also be used as medicine, offering broad farming prospects. Below we introduce in detail earthworm farming techniques and methods for achieving high earthworm yields.
I. Earthworm Living Habits
To raise earthworms well, you must first understand their living habits and know what kind of environment they prefer, so that you can create good rearing conditions for them.
1. They like warmth. 15°C-25°C is the optimal temperature. To create the optimal temperature, cover with a plastic tunnel or plastic sheeting in winter, and cover with rice straw in summer, sprinkling more water to cool down. They hibernate at 0°C-5°C, freeze to death below 0°C, die above 40°C, and stop growing above 32°C. In the Beijing area, cover the tunnel and plastic sheeting on October 25, and remove them on April 10 of the following year. In this way, the earthworms grow until December 20, and from then until February 10 of the following year they are basically in dormancy. From February, to prevent the earthworms from escaping due to excessively high temperatures, pay attention to removing the covering in time. After the 10th, they gradually enter the optimal temperature range. At this time, special attention must be paid to the plastic sheeting on hot days. This is the busiest period: uncover the plastic sheeting around the edges during the day, cover it promptly in the morning and evening, and water in time to keep it moist. Thus from March to June 10 is the spring peak egg-laying period for earthworm growth. During the high-temperature period, prevent heatstroke and cool down; it is best to water once a day. August 20. After June 10 to August 20 is the summer period, after which they gradually enter dormancy. Late September is the second peak egg-laying period for earthworms.
2. They like moisture and fear dryness. The water content in an earthworm's body is about 80%, and the feed is required to have a water content of 60%-80% (judged by squeezing the material in your hand until water drips between the fingers). Therefore, the water content of the rearing bed is required to be above 60%. Thus, water must be applied once a day or every 1-2 days. Do not use too much water at once, but it must soak through and connect with the lower layer of material. Water in the middle of the day in winter, in the evening in summer, and during the day in spring and autumn.
3. They like darkness and fear light. Earthworms hide by day and come out at night, and can be seen moving and foraging in moonlight. The rearing bed should be covered with rice straw to maintain moisture and block light.
4. They like air and quiet. Loose feed is beneficial to earthworm growth. Before feeding, turn over the bed once (about 20 cm thick) to increase aeration. This point is very important. Over the years, we have found that in the bottom layer of the bed soil, the number of earthworms is very small, although feed is still present. The main reason is the lack of air, which is unfavorable to earthworm growth.
II. Choosing a Suitable Farming Site
There are many choices for earthworm farming sites. In front of and behind the house, in courtyard open spaces, as well as old wooden boxes, waste buckets, pots and jars, bamboo baskets, brick pits, and seedling warming beds, medicinal earthworms can all be raised. However, if large-scale farming is chosen, sites with open space such as vegetable fields, orchards and nurseries are generally selected. While raising earthworms, the soil environment can also be improved and soil nutrients increased, achieving dual use of the land.
1. Mulberry Orchard Farming Method
Generally, choose a mulberry orchard with relatively flat terrain that can be irrigated and drained. Dig trenches 40 cm wide and 20-25 cm deep along the rows between mulberry trees, add preliminarily decomposed organic fertilizer such as horse and cow manure, straw, weeds, pig and sheep manure, dead leaves, rotting grass, etc., about 5000-7500 kg of organic material per mu, cover with 10-15 cm of soil on top, and put in seed earthworms for breeding. The number released depends on the earthworm species and individual size. Green manure or green feed can be planted between the rows, and a drainage ditch should be dug every 5 rows. Keep the water content at about 30%.
2. Feed Field Farming
This includes land planted with comfrey, broad beans and other perennial green feed, all of which can be used for farming. When farming, choose a level feed field, and dig an irrigation and drainage ditch every 10 rows. Between the comfrey rows, dig trenches 15-20 cm wide and deep, apply organic feed in the trenches, cover with about 10 cm of soil on top, and then put in green earthworms for breeding. Regularly pay attention to irrigation or drainage, and keep the soil water content at about 30%.
3. Vegetable Garden Farming Method
Vegetable gardens have sufficient water and fertilizer conditions and are carefully managed, which is most favorable for earthworm growth and reproduction. In a vegetable garden used for raising earthworms, apply 7500-10000 kg of high-quality organic fertilizer or decomposed rotten vegetables, garbage, etc. per mu. After the vegetable seedlings emerge, release seed earthworms for breeding. In vegetable garden farming, the application of chemical nitrogen fertilizer and certain pesticides should be reduced. Adult earthworms can be harvested in stages along with vegetable management.
4. Orchard Farming Method
Using the open space under fruit trees to raise earthworms both makes full use of the land and promotes fruit tree production. If raising green earthworms, the method is similar to the mulberry orchard farming method. If raising Eisenia fetida (red earthworm), then under the fruit trees along the tree rows pile decomposed cow, horse and pig manure in beds 1.5-2 m wide and 0.4 m high as earthworm rearing beds. Leave a walkway between each rearing bed, and dig a drainage ditch every 2 rearing beds. Cover the feed surface of the rearing bed with rice straw or wheat straw. Keep the humidity at 60-70%. Cover with plastic film on rainy days to prevent soaking by rainwater.
5. Air-Raid Shelter Farming
Urban air-raid shelters are basements, warm in winter and cool in summer, with relatively high surrounding humidity, suitable for raising red earthworms. The farming method is the same as box rearing and pit-pond rearing. A lamp can be lit at night, which both prevents escape and provides a certain light source beneficial to earthworm growth.
III. Basic Methods of Earthworm Farming
1. Farming density.
For raising earthworms with cow manure, the number of seed earthworms should be controlled within 10,000 per sq m; the production earthworm population should be 3 kg per sq m (20,000-31,000 individuals); in the early stage, young earthworms 30,000 per sq m, later decreasing to 20,000.
2. Timely supplementary feeding
Usually in about 20 days the earthworms can turn all the pig manure into earthworm castings, at which point supplementary feed is needed. When supplementing feed, new material can be spread over the original feed. Determine the amount added according to the earthworms' food intake. The feed should be spread evenly, then add rice straw, and water frequently to keep it moist.
3. Reasonable watering
In the process of raising earthworms, to ensure normal earthworm growth, especially in summer, water at least once a day. The water must not be polluted, and the flow rate should not be too large. It must soak through so that the upper and lower layers of material connect. It is best to water in the early morning or evening when the temperature is lower.
IV. Techniques for High Earthworm Yields
In the process of earthworm farming, the fermentation treatment of earthworm feed (poultry manure, distiller's grains, bagasse, leftover food, waste blood and animal offal, etc.) is key. If the feed is not fermented or not thoroughly fermented, harmful gases will be produced, and the pH will be too high or too low, which may cause earthworms to escape, stop producing cocoons, or even die. Using EM stock solution to ferment the manure material greatly shortens the fermentation time and reduces the odor. Moreover, after the feed is well fermented, the pH value will naturally reach 6.5-7.5 without adjustment, and it can be fed directly. Feed utilization is greatly improved, earthworms produce more cocoons, reproduce quickly, and yield increases by 2-3 times. The specific method is as follows:
1. Building the pile
First spread a layer of dry material (10-15 cm thick) with rice straw and straw (cut into small pieces is better), then spread manure material on the dry material (4-6 cm thick), and repeat this for 3-5 layers. After each layer, spray water with a watering can (the EM stock solution is added to the manure pile at this time; one ton of manure material requires 10 kg of EM mixed with about 100 kg of water), until the water seeps out. If using garbage, use one layer of garbage and one layer of manure, with no limit on length and width, and cover tightly with a film. If using 100% manure material, first dry the manure material to about 50-60% dry, then build the pile, sprinkle with EM diluted in water, and cover tightly with a film.
2. Turning the pile
In seasons with relatively high temperatures, generally the temperature inside the pile rises noticeably the next day, can rise to 60°C-70°C in 4-5 days, and then gradually falls. When the temperature inside the pile drops to 40°C (this process takes 12 days), turn the pile, moving the top to the bottom and the sides to the middle, and add more EM dilution. Turn the pile 2-3 times in winter and 1 time in summer.
3. Feeding
After the feed fermentation is completed, open up the feed, sprinkle water to dissipate heat, and then it can be used. When feeding, the top-adding method and side-feeding method are generally used. The top-adding method is to spread feed over the feed that has already been eaten by the earthworms, once every 10-15 days. The side-feeding method is to remove part of the feed that has already been eaten, then add new feed on one side, and add to the other side next time.
V. Disease and Pest Control
1. Feed poisoning
If earthworms are found to suddenly become paralyzed locally or even throughout the body, discharge yellow or grass-colored body fluid from the back, and die in large numbers, this means the newly added feed contains toxins or toxic gas. At this time, quickly thin the material bed, remove the toxic feed, loosen the base material of the material bed, add earthworm castings to absorb the toxic gas, and let the earthworms burrow into the bottom to rest. They will slowly adapt.
2. Protein poisoning
If earthworm bodies are found to have local scorching, with one end shriveled or one end swollen before death, and the surviving earthworms refuse to eat, showing a trembling sense of fear and obvious emaciation, this is protein poisoning caused by improper proportioning of feed ingredients when adding feed. The protein content of the feed ingredients must not be too high (the manure material must not exceed the standard when making the base material), because the ammonia gas and foul odors and other toxic gases produced during the decomposition of protein feed can cause protein poisoning in earthworms. After discovering protein poisoning, quickly remove the improper feed, spray clean water, loosen the material bed or add a buffer zone in order to detoxify.
3. Oxygen deficiency
If earthworms are found to have a dark brown, lusterless body color, weak bodies, and slow activity, this is oxygen deficiency in earthworms caused by insufficient oxygen. The reasons are as follows: (1) The manure material was not completely fermented, producing excessive harmful gases such as ammonia and alkanes; (2) The environment is too dry or too wet, blocking the earthworms' epidermal pores; (3) The earthworm bed is covered too tightly and air cannot circulate. At this time, identify the cause promptly and deal with it. For example, remove the base material, continue fermentation, and add a buffer zone. Spray or drain water so that the moisture of the base material soil is kept at about 30-40%. When it is warm at noon, open doors and windows for ventilation or uncover the covering, and install exhaust fans. In this way, the condition can be resolved.
4. Excessive stomach acid
If earthworms are found to have spasmodic nodules, red and swollen clitellum, thickened and shortened bodies, increased mucus secretion over the whole body, crawling in circles on the rearing bed, or burrowing to the bottom of the bed and refusing to eat or move, and finally turning white all over and dying, and some diseased earthworms show body segment rupture before death, this indicates that the earthworm feed contains too much starch, carbohydrates or salt, which causes acidification through bacterial action and leads to excessive stomach acid in earthworms. The treatment method is to uncover the covering to ventilate the earthworm bed, and spray alkaline substances such as soda water or gypsum powder to neutralize it.
5. Edema disease
If earthworms are found to have swollen, enlarged bodies, to be in a daze or desperately crawling outward, with body fluid emerging from the dorsal pores, stopping eating and then dying, and even causing earthworm cocoons to rupture or newly laid earthworm cocoons to fail to close at both ends and become moldy and rotten due to bacterial infection, this is caused by excessive humidity in the earthworm bed and excessively high pH of the feed. At this time, reduce the humidity and remove the earthworms that have crawled to the surface to another pond. Add superphosphate powder or vinegar residue or alcohol residue to the original base material to neutralize the pH, and after some time try feeding the earthworms again.
Earthworm bodies show spasmodic nodules, become thick and short, with red and swollen segments, increased mucus secretion over the whole body, and the earthworms turn white and die. The cause is that the earthworms ate toxic feed, for example if pesticides were sprayed near the livestock manure pile, if polluted water was poured on the earthworm bed, if chemical fertilizers or pesticides had been stored where the earthworms were temporarily kept for fattening, if the containers used to transport the earthworms had contact with toxic items, or if the temporarily kept earthworms were placed on plastic film that did not leak and the feed fed was too wet, and the environment in which the earthworms lived was excessively humid, then when the temperature is high the earthworm bodies turn white and a few die. If this situation occurs due to toxic harm, spray water multiple times to wash away the harmful substances with water, and also frequently add concentrated feed such as rice bran and wheat bran. If earthworms kept temporarily indoors become diseased, they must be moved away. If the earthworm bodies turn white due to excessive humidity, add fermented dry livestock manure or concentrated feed, mix it with the original wet material and earthworm castings, and remove the plastic film. If a few deaths are found, immediately move them into the earthworm bed for rearing, so that the earthworms still able to move can recover their health.
VI. Earthworm Harvesting Methods
Traditional earthworm harvesting methods include: the flooding method, the trapping method, the light-driving method, the red-light night-catching method, and the direct-catching method. Here we introduce a new screening method: enclose a perforated iron mesh into a cylinder, use a machine to drive it to roll continuously in place, introduce the soil containing earthworms from one end, and widen the opening at the other end. Through the rotating centrifugal force, the earthworms and soil will gradually separate, and due to gravity they will fall on the two sides of the opening at the other end respectively. At this time, place a collection bag at the position where the earthworms fall at the other end, and the separated earthworms can be harvested. The advantages of this method are: first, it saves labor costs. According to practical experience, using this method one person can harvest nearly 400 jin of earthworms per day; second, because a perforated iron mesh is used, earthworms that have not yet grown up and earthworm eggs will fall through earlier, so excessive harvesting will not occur, saving the cost of purchasing earthworm seedlings later.
VII. Development of Earthworm Products
Earthworms can be developed into a wide variety of products. In addition to the traditional uses as poultry feed and as fishing bait for anglers, they can also be used for human consumption. Many earthworm foods have already been developed, such as earthworm wine. Earthworms themselves can also be used to make medicine. At present, lumbrokinase can be scientifically extracted from earthworms for treating cerebrovascular infarction and other diseases, with obvious efficacy, and can be used for clinical treatment. In addition, earthworm castings, after collection and screening, can be sold directly to the market for use as fertilizer.
Finally, Qinnong Network would still like to remind everyone that although the economic benefits of raising earthworms are currently extremely high, with experienced farmers earning about 30,000 yuan per mu, earthworms still belong to specialty farming after all, requiring a certain level of farming technology and a complete set of product sales channels. Without making the above preparations, there is a great risk of losing everything.