Restoring the Soil - Canadian Foodgrains Bank

52Decision Tree Guidenot dry-season rotations. These systemsviolate the gm/cc rule of not spendingmoney or effort on transportation, butthousands of farmers use this system inBurkina Faso. These systems do usuallyrequire a lot less labor than collecting andtaking animal manure out to the fieldsfrom the homestead.28. Thailand. Lablab beans, cowpeas and ricebeans are each grown during the dry season inmaize fields in northern Thailand. The practice wasoriginally developed by the farmers mostly to keepdown the weeds and maintain soil moisture, butthese gm/ccs now are also being consumed andsold in the local market.rejected by farmers.45. Hedgerows. These are not usuallyvery popular among farmers because theyoccupy land that farmers’ crops couldbe using and because they often requirepruning during the wet season, when thedemand for labor is highest. This is why“alley cropping” was almost universallySeveral things can be done to make hedgerows less objectionable. First, farmersshould be consulted about the distance between hedgerows. If they choose (asthey likely will) a distance such as 25 m between hedgerows, we should agree eventhough the impact on soil fertility will be minimal due to this large distance. Intime, when they see the impact of the hedgerows on soil fertility, they may wantto add a hedgerow between each of the two they already have, making the distance12 m instead of 25 m. Perhaps a better practice would be to add a secondrow of bushes to the already existing headgerows.Second, if dispersed trees are planted in the hedgerows, the hedgerows will be lessobjectionable, because they will be occupying the area of maximum shade, wherecrop growth may be somewhat poor anyway if the pruning is not done heavilyenough. Furthermore, the hedgerows will be seen as part of a total system withbenefits of moisture retention and crop shade in addition to soil fertility.Third, if on hillsides the hedgerows can double as contour hedgerows to preventerosion, they will be more acceptable. This is the case on several islands in Indonesia,where the alley cropping hedgerows have met with considerable acceptance.Fourth, some hedgerow species, such as nyama (Piliostigma reticulatum), canbe pruned to ground level, which gives the field crops a head start. Nyama isa native bush in much of the Sahel, from Senegal to Kenya. It is a perennialwhose leaves do an extremely good job of fertilizing the soil. It is very resistant toanimals (although some protection may be required the first year) and maintainsits leaves until June, when the rains come. A field that is no longer fertile can beplowed and nyama seedlings planted, either from a nursery or using seedlingsthat volunteer near where the bushes already exist. The seeding rate will dependon the number of seedlings available, but they could be planted one seedling