Agroforestry Services: Nitrogen  Fodder: Bank  Fodder: Pod  Management: Standard  Other Systems: Evergreen ag  Other Systems: FMNR  Other Systems: Parkland  Regional Crop  Staple Crop: Balanced carb

White acacia succeeds from the tropical to warm temperate zones, thriving in climates that are characterized by long summers, or a dry season with long days[303 ]. It grows best in an altitude range of about 270 - 2,700 metres[303 ]. It grows best in areas where annual daytime temperatures are within the range 18 - 30°c[418 ]. It is intolerant of frost[325 ]. It prefers a mean annual rainfall in the range 400 - 1,000mm, but tolerates 250 - 1,200mm[418 ]. It has succeeded in areas with 1,800mm and, provided there is access to underground water, it can grow independent of rainfall, such as in the Namib Desert[325 ]. Requires a sunny position, growing best in a coarse-textured, well-drained alluvial soil[303 ]. It tolerates seasonal waterlogging and saline conditions, but cannot withstand heavy clayey soils[303 ]. Prefers a pH in the range 5.5 - 7, tolerating 5 - 7.5[418 ]. The tree has roots that can penetrate 40 metres into the soil to find groundwater and thus help it to withstand drought, even for periods of several years[418 , 774 ]. Observed production of seed by isolated trees is an indication that there is no strict self-incompatibility[303 ]. The plant has an 'inverted phenology' - it is deciduous during the wet season and produces its leaves in the dry season[303 ]. Initial top growth can be rather slow as the plant focuses on developing the tap root. One year old plants can be up to 80cm tall and up to 450cm tall by the time they are 5 years old[774 ]. On very good sites this can be increased, with trees up to 10.5 metres tall at the age of 7 years[774 ]. Plants commence flowering in about their seventh year and subsequent flowerings occur 1 - 2 months after the start of the dry season, lasting for up to 5 months[303 ]. The tree responds well to coppicing and regrowth is usually quite vigorous[303 , 774 ]. For bees, the tree has the advantage of producing its flowers at the end of the rains while most of the Sahelian species flower just before or during the rains. It therefore becomes their main source of pollen and nectar at this time[303 ]. This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[299 ].

Carbon Farming

• Agroforestry Services: Nitrogen  Plants that contribute to nitrogen fixation include the legume family – Fabaceae.
• Fodder: Bank  Fodder banks are plantings of high-quality fodder species. Their goal is to maintain healthy productive animals. They can be utilized all year, but are designed to bridge the forage scarcity of annual dry seasons. Fodder bank plants are usually trees or shrubs, and often legumes. The relatively deep roots of these woody perennials allow them to reach soil nutrients and moisture not available to grasses and herbaceous plants.
• Fodder: Pod  Fodder plants with pods.
• Management: Standard  Plants grow to their standard height. Harvest fruit, seeds, or other products. Non-Destructive management systems.
• Other Systems: Evergreen ag  A subset of agroforestry providing green cover on cropland.
• Other Systems: FMNR  Farmer-Managed Natural Regeneration.
• Other Systems: Parkland  Africa - Trees scattered throughout cropland. An Irregular intercropping system.
• Regional Crop  These crops have been domesticated and cultivated regionally but have not been adopted elsewhere and are typically not traded globally, Examples in this broad category include perennial cottons and many nuts and staple fruits.
• Staple Crop: Balanced carb  (0-15 percent protein, 0-15 percent oil, with at least one over 5 percent). The carbohydrates are from either starch or sugar. Annuals include maize, wheat, rice, and potato. Perennials include chestnuts, carob, perennial fruits, nuts, cereals, pseudocereals, woody pods, and acorns.