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已出版: 1995-06-19


Dave Morneau in the Central Plateau of Haiti asked us about the Haitian beekeepers’ belief that neem (Azadirachta indica) or chinaberry (Melia azedarach) blossom nectar is harmful to honeybees, since leaves and seeds are widely used to control insects. We checked ECHO’s library and found no written evidence to support this concern. 

Neem: A Tree for Solving Global Problems reports that neem is benign to most beneficial insects, and “[insects] that feed on nectar or other insects rarely contact significant concentrations of neem products.” The authors cite a study which found that “only after repeated spraying of highly concentrated neem products onto plants in flower were worker bees at all affected. Under these extreme conditions, the workers carried contaminated pollen or nectar to the hives and fed it to the brood. Small hives then showed insect growth regulating effects; however, medium-sized and large bee populations were unaffected." 

Beekeeping in India mentions that neem is an erratic producer of nectar, but that the chinaberry does not seem to be visited by bees. Another source lists neem in its list of common nectar sources for Sri Lanka, flowering in May and June. A table in Agroforestry in Dryland Africa shows that providing fodder for bees is a major use of neem and a secondary use of chinaberry. Finally, the thorough Handbook of Plants with Pest Control Properties does not include either neem or chinaberry in its group of plants which are toxic to honeybees. A visitor from India told us that bees are used to pollinate the extensive neem orchards in his area. 

Based on our research, we cannot confirm the Haitian farmers’ concern that neem could harm their beehives. Please write us if you have experience or further information on this topic.

Joy Niland, Food Gardens Foundation, South Africa. "With regard to keeping birds out of the garden (EDN 384), an idea which has proved quite effective in some places is to secure thin, darkcoloured string in a zigzag pattern across the bed. The string should be about 3 cms above ground level. When the birds try to walk in the beds they trip over the string and generally fly off to less hazardous places. The string also acts as a deterrent to small animals.”

Cory Thede, Santarem, Brazil, tells about his experiences with some leafy green vegetables in the Amazon basin, and with iguanas, a serious garden pest in the area. “We have a marked dry season of 5 months or so. Moringa (M. oleifera) did well in the city but didn’t grow well in infertile rural soils. Maybe calcium from the cement, and possibly other nutrients that accumulate in the city, made the difference. Iguanas like it…they try to climb even a young plant to eat the leaves, but it is fragile and they knock it over. Use the young leaves to avoid the tough stems of the older leaves; they are easier to prepare for cooking. A moringa hedgerow is a convenient way to assure a steady supply of young leaves." 

He also shares observations on other vegetables. ECHO grows all of these, but some are propagated only by cuttings that do not survive overseas mail. If you visit ECHO you can get cuttings then, or we can ship them to you just before you leave the States. 

Chaya, the first plant Cory mentions, is so drought resistant that we have successfully sent cuttings to Africa, Asia and Latin America (EDN 182). "Chaya (Cnidosculous chayamansa) is iguanaproof! Leaves are within their reach, but they don’t touch them. Though it is exceptionally productive in some parts of the world, it grew erratically here I think a dry season mite stunted its growth. I didn’t see much use being made of it. 

"Propagate chaya by OLD (grey, not green) thin stalks if they are to be transported, as these have less pith and weight. (For immediate planting, any part will do.) When it arrives, cut off any rotting parts but you probably don’t need to make new cuts if it’s healing well. Be sure to plant it right side up, so leaf scars look like smiles not frowns. The bud is above the leaf scar. Leaves are flavorful when cooked with ham, onion, salt, and pepper. [ED: I prefer them with salt and vinegar].

"They also dry and powder cassava leaves and add them to foods this is a very handy form of storage, especially for moms who don’t want to leave the house to collect leaves during the cooking. Eating leaves is not too common a practice here, so maybe the powder disguises them well enough to be accepted, especially when used to enrich soups.

Katuk (Sauropus androgynus) and false roselle (Hibiscus acetosella) are easy to start from cuttings of any part of plant, old or new growth (even in the dry season). Strip off most leaves and put the cutting directly into the ground under partial shade. They are survivors and palatable to most people. The false roselle was especially popular because of the redpurple color and sour flavor. Katuk is a light producer of greens compared to the others. [ECHO can send seed of false roselle.] 

Brazilian Spinach (Alternanthera sissoo, also Samba lettuce, sissoo spinach) forms a thick groundcover. It creeps and roots from nodes over a large area. It responds well to fertilizer. A pest (centipede?) eats holes in the leaves at certain times of the year, but this only damages the appearance a bit. Once planted, it can be maintained permanently, as a perennial. Propagate it by cuttings placed in the ground, with some shade (palm fronds for a week or two); it is very hardy, but keep it moist while rooting. It grows fast but is not invasive. Brazilians usually eat it raw in salads with oil/vinegar, tomato, and onion, although the literature recommends cooking it. This, together with lettuce and collards, are the most common greens in the area. In fact, it is betterliked than lettuce. Branches are sold in the market pull leaves off the stems and eat the young vine tips. 

Okinawa ‘purple’ spinach (Gynura crepioides) looks similar to a local weed both are purple under the leaves, but the weed has an upright growth habit and is an annual. The cultivated type, which may be a selected weed, is perennial, branching, and tends to fall over making a bush. It grows very well and is pestfree. It has a tasty, pinelike flavor and did well in poor soils. Mix it with other vegetables; the unique flavor may be too strong on its own. 

Iguanas or lizards are a big garden pest. They are 12 feet nose to tail, with green/brown/black colors. They eat both false roselle and katuk not chaya and I avoided them by "hiding” or “camouflage planting” in weeds rather than on bare soil, which the people prefer around their houses. People like bare yards, without grass or groundcover plants just ornamentals. 

“Some control the iguanas by draping old fishnet over seedbeds for transplants. The elevated gardens are easily covered. [Most gardens are on platforms. See EDN 30.] Seedlings can grow up through the net, and iguanas/lizards avoid it. I killed a few iguana pests in rat traps. They hide in scrap woodpiles, so keep these away from the garden. In another area (Jurutí area in N Brazil), iguanas ate the pigeon peas, but in Santarem, they didn’t touch them perhaps from the resemblance to a similar-leaved stinging vine that grew as a yard weed in Santarem.”

Michi Vojta, a Peace Corps volunteer in Kenya, asked about Porcupine Control. “One problem that discourages planting of tuber crops (sweet potato, cassava, etc.) is porcupines and other burrowing animals that substantially reduce harvest. Any suggestions to protect foods from the burrowing ones?" 

Porcupines live in many habitats, from tropical forests to sandy semiarid regions, and create extensive underground burrows with several entrances where they shelter and breed. Most are nonselective vegetarians and can be major pests in orchards or areas of reforestation by eating all parts of seedlings and girdling mature trees. In cultivated areas, they may damage root and tuber crops, pumpkins, melons, maize, vegetables and irrigation tubing. They usually forage alone at night. Porcupines are hunted by large birdsofprey, wildcats, pythons, scavengers, and even, in various countries, for human food. 

Joe Brooks with the Denver Wildlife Research Center writes that porcupines in Pakistan died when they ate bait set out to poison wild boar. The bait was wheat flour or grain, corn oil, brown sugar/molasses, anticoagulant poison (warfarin or coumatetralyl) at a concentration of 0.025%, and enough water to make a stiff dough, rolled into small balls. He suggests that since the porcupines damage root crops, it might be worth trying cubed pieces of the affected crops mixed with the anticoagulant concentrate for a bait. (See EDN 341 for information about using Gliricidia sepium as a similar rodenticide.) It is also possible to fumigate the burrows with 510 aluminum phosphide tablets per burrow system, but care must be taken to close all entrances to the burrow system except the one to be treated. 

Porcupines find their food by hearing it fall, feeling it with their whiskers, or with their keen sense of smell. K.S. Ramalingam, visiting ECHO from India, says it is important to make rat baits smell appealing with ghee butter or groundnuts, and to stir them with a stick to avoid imparting the human smell. We have heard of fresh mint tea being poured on the ground or sprayed on plants in Thailand as a rat repellent; similar techniques might work for porcupines. To keep rodents off the bark of young trees, farmers in the Solomon Islands wrap them with a local thorny vine and make bamboo "collars” for the trees. Indian farmers grow sunflowers and build perches to encourage owls and birdsofprey to perch in their fields and eat rodents. Might the sunken bucket trap in EDN 201 be adapted for porcupines? If anyone in our network has more ideas for control of burrowing animals, please let us know so we can share your idea with others.

Cite as:

ECHO Staff 1995. Echos From our Network. ECHO Development Notes no. 49