Restoring the Soil - Canadian Foodgrains Bank

Decision Tree Guide45more than 1,000 mm per year. These systems would be the same as those in #29.Go to #29.32. Improved fallows where the animals are kept away from the fields. In theseareas, improved fallows can use any one of several species. Try mucuna (Mucunaspp.) (Photos 15 and 23) and pigeon pea (Cajanus cajan), along with the jackbeanand tephrosia.23. Honduras. This mucuna was planted in anotherpart of the same field as shown in photo 15. Themucuna has only been growing for 45 days, in spiteof the poor condition of the soil. For extremely poorsoil, jackbeans will grow better than mucuna.24. Honduras. The mucuna we use as a gm/cc must not be confused with the itchy type ofmucuna, which has a cover of small hairs on thepod (the variety to the right). This itchy kind shouldnever be used in farmers’ fields. Some farmerstraditionally use the itchy kind (e.g., in centralGhana). These farmers should be told that the nonitchykind is just as “strong,” meaning it fertilizestheir fields just as well.This may be the ideal situation formucuna, a gm/cc species that has, in thepast, been tried in many situations thatwere not ideal for it. If there is enoughrain mucuna will grow most of the year,or will reseed naturally in January (Julyin the southern hemisphere). The use ofmucuna usually results in a very good,high-nitrogen level improved fallow thatis also very efficient at eliminating mostweeds. The farmer obtains a virtuallyweed-free, fertile soil in 12 months (Photo13). The mucuna seed can be broadcasteither when there is no vegetation becausethe field has just been plowed or thevegetation cut, or when there is naturallyvery little vegetation, such as just beforethe rains start (although the field musthave been dug or plowed sometime withinthe last year or so). In either case, themucuna seed should be planted whenunder normal climatic conditions therewill be significant rainfall for at least thefollowing three or four months. The use ofmucuna can restore the soil in six monthsto a year. (See, for instance, S1 and S77.The mucuna need not be a perennialmucuna, like that used in Vietnam.)Mucuna is the best-known of all the gm/cc species (Photo 24). It is also probablythe most widely used gm/cc species in theworld, since it is extensively grown in theAmericas, Asia and Africa. This may seemstrange, given that it produces no easilyedible bean or widely useful by-product.The beans can be eaten, and are high inprotein, but only after some major