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已出版: 1996-10-19


CINDY FAKE, with Food for the Hungry in Mozambique, wrote about her experiences controlling locusts with a tea made from leaves of the neem tree (Azadirachta indica). Unfortunately, her seed shipments from ECHO were delayed and did not germinate upon arrival, but she found (dried) seed from another source and now has 250 seedlings. “We have regular invasions of red locust. During the last invasion when they were devouring everything in their path, our research plots of maize and cowpea were completely untouched. They had been treated with a neem-leaf mixture, as we don’t have seed yet. The Locusts went for synthetic-pesticide-treated plots, but not neem! Now all the farmers and extensionists in Sofala province want neem trees.” We thought this was important enough to ask some followup questions.

Q. What led you to choose leaves rather than seeds to make the spray?

A. We know that seeds contain higher concentrations of active ingredients than leaves, but our first trees were started only two years ago. We do not yet have seed producing trees, and when we do, we want to use the seed to multiply the trees.

Q. Would you tell us precisely how the tea was made?

A. We used a mortar and pestle to pound 500 g of green leaves, added 10 liters of water, and left it overnight. The following day the mixture was strained through a cloth and a small amount of soap was added to help the spray stick to the leaves. The straining process is quite slow. In order to 54-4 reduce the straining time, we also tried mixing the pounded leaves with only 5 liters of water on the first day, leaving it overnight, and adding the other 5 liters of water after straining, but this was less effective. On the research farm, botanical sprays are applied with backpack sprayers. Most farmers use small brooms that they make from grass or leaves and apply by shaking the solution onto the leaves until it drips off.

Q. How large were the plots?
A. The research farm is 4 ha, but only selected parts (about 1 ha, not-contiguous) were treated with neem.

Q. Did you notice any locusts landing on your crops, then leaving, or did they just avoid them altogether?

A. The locusts did land on the neem-treated crops, but left without feeding.

Q. Were the protected maize and cowpea plots surrounded by other maize and cowpea plots that were destroyed, or were they isolated?

A. There were other maize and cowpea plots surrounding the neem-treated plots, and they were badly attacked. Most of this area consisted of our most valuable and/or vulnerable fields of maize and sorghum during the red locust attack. We also used neem tea throughout the season as one of six treatments on a replicated trial of botanical pesticides in cowpea. In this trial, the red locusts caused varying degrees of damage to the other 5 treatments, but only minimal damage to the neem-treated plots. We have not yet completed data analysis, so cannot say anything about the effect on final cowpea yield. Cindy’s term has now ended, so anyone wanting to communicate further should write to Tracey Henderson or Tonette Demagante, FHI/Mozambique, P. O. Box 1390, Mutare, Zimbabwe. E-mail spear@maf.org.

Meg LaVal in Costa Rica wrote of her successes with vermi composting, or using worms to create compost quickly. “I have worked intensively with worms for 6 months and had good results. Monteverde is at 1500 m elevation, with marked dry (Dec mid May)/wet seasons with about 2500mm of rain a year. "In Costa Rica, like many places in the world, people look on garbage as a problem, instead of seeing it as a source of organic matter to replenish our much-depleted soils. We got our California red worms from Paul Vasquez, a microbiologist neighbor who was already doing vermicomposting on a fairly large scale, and helping train the personnel at the coffee processing plant. Worms are also available from several experiment stations. We have attracted numbers of the wild local kind as well. However, since the rains have started they have migrated outward, much faster than the California reds. "The main thrust of our project in Monteverde is to compost the organic waste of Stella’s Bakery (and restaurant) and the manure from Meg’s Stables. The dry season is also the time of higher tourism and hence more garbage. During this time we mix ½ manure and ½ organic garbage in 1x3m beds. These beds are constructed directly on the ground, with an edging of plastic sheeting draped over wire (20-30 cm high) to hold the organic material. We mix and wet each bed daily for 6-10 days (at this time the garbage should not smell bad, particularly not acid or vinegary). After 6-8 days the bed is usually ready for a few test worms. We sprinkle a few (10-20) on the surface. If they find it to their liking, they rapidly disappear. In a day or two we dig around and find them and see if they look healthy and active; if so, we add another 3,000.” [Ed.: Authors give varying advice on how long to compost the materials before adding worms, ranging from a week to a month. The principle is that hot compost can burn the worms, so be sure the material is over that initial heating.] “In the dry season, we wet these beds twice a day: in the morning and around 2 pm. We also turn them 1-2 times a week to aerate them and keep them from becoming too compacted. [Ed.: Moisture content should be about 75%, which is wet enough to feel moist but not wet enough to squeeze water from a handful of soil. Drainage is necessary. A SIFAT publication mentions using run-off from worm beds as foliar fertilizer.] "When the material looks like dirt (6 or so weeks) it is time to trap out the worms. We push all the dirt to the center of the bed, and put aged horse manure/garbage mixture at the ends. This attracts the worms, which you can either move to another bed by picking them up material and all, or by leaving them there and removing the finished compost and adding fresh material to replace it. If there are many eggs you will need to wait until they have hatched (they hatch in three weeks), and the young have also migrated. To help encourage the last of the stragglers to leave the dirt, stop watering the middle of the bed. If you are particularly short of worms, you can hand-pick the last few from the dirt when you take it out of the bed. After all the eggs have hatched and we have trapped all the worms, we take the finished product to our organic garden. Several people have offered to buy the finished compost, but we haven’t had more than we can use yet. We started with 5 kilos of worm/dirt/egg mixture, which is how you buy them here. Six months later it was estimated that we had 300 kilos.

"Several side projects have also sprouted from the main one. Some friends expressed interest in a household version. Thinking that not everyone would care to stoop over to deal with their worms, I constructed a 1x1m box on legs, with drain holes. I put slightly decomposed hay waste in it as bedding, then added 1000 or so worms. Daily, I bury a 54-5 large double handful of garbage around the edge of the box. By the time I make it all the way around, they have eaten all the original garbage, and I can start around again. This has great appeal to housewives, as they can have it right outside their back door. Several have made their own boxes so they could get started, as they really appreciate the end product for their flowers and gardens. After your article on tire gardening on roofs (EDN 52-3), I think you could raise worms in the tires, trap them out and plant that tire, moving the worms to a new tire. "I also had several pickup loads of manure/dirt/hay waste from the horse corral, so I made several larger woodensided enclosures, (2x3m) to put this waste in. The worms loved this also, although we were not able to turn it, as it was much deeper (50-60 cm). We are just starting our first rainy season with worms, and it is evident that they will definitely need some kind of roof. I have made 3 smaller beds under a shed roof, and thrown some old metal roofing over the bigger wooden beds outside. I think we will abandon the plastic beds on the ground until drier weather. One of the disadvantages to the environment being wet all around the beds when they are outside is that a certain number of the worms strike out on their own, and without any cover, I think they would actually drown in some of our gully washers! "The Environmental Education Dept. of the Monteverde Cloud Forest Reserve encourages people to grow organic gardens, to recycle, and to use worms. They have given a workshop to interested locals, well attended by a wide crosssection of the community. The Reserve plans to give out a few worms as starters, and I have also given out several kilos to neighbors. "The Santa Elena Co-op (Cafe Monteverde) is successfully using the worms to compost the skins and pulp left at their coffee processing plant. Traditionally this is dumped in rivers, and is a large source of contamination in coffeeproducing countries. In a recent news program it was stated that ½ the coffee processing plants in Costa Rica are now using these worms. At our co-op, the coffee farmers are encouraged to use the compost produced to put back on the coffee patches. We have just started getting results from the first plantings in this compost. So far we are very pleased. The plants given compost are greener and more vigorous even than the plants planted in our organic garden which has had organic matter added every time we plant (depending on the crop 3-4 times a year) for the past 16 years. "Although the project is a few meters from Stella’s Bakery, there is no disagreeable odor. In fact the customers who wander through the hedge and discover the project are usually fascinated. So far we haven’t had an excess of worms (except for giving away some starters to neighbors). However I believe that chickens or fish would love them. Paul Vasquez talks of making a solar drier and drying and grinding them for cattle/pig feed and even feeding the compost to tilapia. "The one predator which has caused problems in this area are flatworms (commonly known as "slugs,” which they are not). These animals wrap themselves around the worms and suck them dry. We have only had the occasional one, but a neighbor had a real plague of them (perhaps because she was dumping only kitchen garbage and it got very acidic and smelly, and the worms were sickly). We added a lot of manure and hay waste and started turning it frequently, picking out any “slugs” we saw, and this controlled the situation.

Cite as:

ECHO Staff 1996. Echos From our Network. ECHO Development Notes no. 54