Restoring the Soil - Canadian Foodgrains Bank

Decision Tree Guide47it on top of the soil (together with the residues of crops such as maize or millet),so the decomposition process will take place more slowly. Leaving the mucunavegetation on the surface is far preferable in nearly all instances especially sincethis practice also saves labor. A fair amount of nitrogen will be lost into the air(it will “volatilize”), but this is normally not a major worry. Smallholder farmersrarely need more than 100 kg N/ha each year.In the case of any of the maize/mucuna systems, if farmers also raise pigs, theycan experiment with using the mucuna to feed them. Mix one part of maize flourwith one part of ground mucuna seeds, then lightly cook the dough to make avery cheap (and therefore profitable) feed for pigs that is just as nutritious as commercialfeeds. See S8.In rare cases, mucuna is not effective. For example, in Kalimantan Island inIndonesia, the local weeds will outgrow the mucuna. But this is rare. Anothersituation is in areas where there are lots of wild animals, such as deer (Kalimantan)or wild grazing animals (near the Sierra de Las Minas in Guatemala) whichcan eat enough of the mucuna to kill it.ICRAF, the World Agroforestry Center, recommends planting trees as improvedfallows. This requires a good deal more labor than just broadcasting mucuna orjackbeans, and it may be several years before you see the desired impact on fertilityor weed control. Nevertheless, if the area’s natural fallows are quite long andfirewood can be sold at a good price, this would be an option worth considering.Gliricidia and leucaena would be among the best species.Pigeon pea was mentioned as another appropriate species for improved fallowswhere animals are kept away from the fields. A description of pigeon peas can befound in #26.Once you have tried and chosen any one or several of these fallow systems, go to#5.33. Noxious weeds? Is your area relatively free of nut-grass (Cyperus rotundus) andimperata grass (Imperata cylindrica)? If so, go to #35. If not, go to #34.34. There are serious weed problems. Use S59 or S89, and then go to #5.35. Do farmers grow grain legumes? Are any grain legumes widely consumed? If so,go to #36. If not, go to #41.36. Local grain legumes. What grain legumes are locally known and consumed, orhave a good price in local markets, with major demand?a) Lablab beans. Go to #37.b) Cowpeas (Vigna unguiculata), rice beans (V. umbellata) or mungbeans(V. radiata). Go to #38.