|Environmentally Sound Technologies for Women in Agriculture (IIRR, 1996, 213 p.)|
|Pests and pesticides|
Bird pests-the main culprits
- Common house sparrow
- House crow
- Common myna
- Blue rock-pigeon
- Red-ringed parakeet
Some types of birds are useful to farmers because they eat insect pests. But some birds do a lot of damage. They can virtually destroy a crop and spoil tons of produce in storage. Scaring harmful birds is an important but tedious task most often the responsibility of children and women.
Crops commonly damaged by birds include pearl millet, barley, maize, mustard, sorghum, sunflower, and wheat. A single bird consumes 8-25 grams of fruit and grain per day. This is a fraction of what a bird can spoil with its scratching, pecking, faeces, and feathers
Birds are difficult to control; they are intelligent, adaptable, and move from place to place. Birds can get used to certain control methods, so it is important to change the method used, to innovate. Farmers are generally seen slinging stones or making noise to scare birds. These are inefficient and uneconomical ways to reduce crop loss.
Cotton and nylon nets
Cotton string nets of different size and mesh are usually spread over mango groves and fruit orchards. Cloth bags are tied to individual fruits, such as pomegranate and papaya. Nylon nets with l/2-inch mesh to prevent the passage of small birds are used on small crop areas. Nets are expensive and not feasible to protect larger areas. They are recommended to protect valuable crops, such as breeder seed for multiplication.
Scarecrows of different sizes and shapes scare birds at the sowing and dough stage of the crop.
Protokrops are simple machines which produce regular loud blasts, effective for scaring birds.
Fire or sudden flashes of light, often accompanied by loud noise, are frequently used in the form of crackers and rocket crackers.
Recorded distress calls are amplified over speakers to drive away perching birds from the fields. This is more expensive than protokrops but more effective in orchards and smaller crop areas.
Polypropylene, metallic, shiny red and silvery white strips, 1015 m long and 15 mm wide, are tied to stakes in the field. Between 50 and 60 such strips, tied from north to south, are required per hectare. The reflection of bright sun rays and the humming sound produced by the wind over the strips scare birds from the fields.
Neem extracts About 23 neem-based pesticides are produced commercially in India. Some of them are: Neemhit
- Neem oil emulsion
- Neem-based emulsifiable concentrate Dispersible powder or granules
Sticky repellents, with or without toxic chemicals, can be painted on tree bark. Among these, lassa, made out of jackhruit milk, gum arable, or commercial coal tar on a silica-based paint are the common products used as stickers to repel birds.
De-oiled neem cake broth (300 g of cake per litre of water) sprayed on maize ears repels birds from fields.
Tightening of husk
Some people wrap maize cobs with leaves. This is effective, but only to a point. At maturity, these leaves dry and loosen their grip, leaving cobs exposed to birds. Parrots peel the cob husks, destroying more than they consume. Bicycle tubes and polyethylene net cones offer effective alternatives. Wrap the tip of cob husks with rubber bands made from 1.75-cm-wide strips of inner tube. Or, use polyethylene net cones. Both are easy to apply and will protect cobs until harvest. They can also be reused, season after season.
Polyethylene net cones or rubber bands protect cobs until harvest.
If the bird pest population is alarmingly high, you can reduce the natural population of birds around the fields and orchards by tipping nests, trapping birds, destroying eggs, and fumigating the perches. Be careful to destroy only nests of those species that damage crops.
Contributor: Dr. L. M. L. Mathur