To the outsider unfamiliar with them, these RSL3 concentration techniques may appear to be destructive and lead to judgments about “deforestation.” It must be kept in mind however that even the extensive pruning seen in Fig. 3 will lead to a re-florescence of this tree within 2 or 3 years (Andersen et

al. 2014). Fig. 3 a A recently pruned subsp. raddiana in the Bishaari area in northern Sudan (Sep. 2010). b The same tree seen in April 2011, already with many new branches. Within a short time (2–3 years) an extensively pruned tree can develop a dense growth of flowering and fruiting branches People use special techniques to strengthen and shape the young tree for subsequent harvesting. From the young subsp. raddiana, Cell Cycle inhibitor the Beja remove branches below canopy height

with a technique they call shiishaknooyt (“helping to mature”). Until about 1980 the Ma‘aza used the similar technique of tasliih, meaning “betterment”. These practices give the tree its typical shape, with one or two trunks and a defined canopy that offers good, accessible shade. Without these practices trees become difficult to approach and use. Most informants say pruning is good for a tree, because it cleans and renews it and keeps it “lighter” and “younger.” In this context, the pastoralists recognize a relationship of symbiosis or mutualism between themselves and the trees. An ITF2357 datasheet Ababda man shared a typical view: “People benefit from the tree and the tree benefits from PIK3C2G them.” The most gentle technique for harvesting acacia seedpods (‘illif Ar., haayt B.), leaves (awraag Ar., bayi B.), and flowers (balla Ar., buukt B.) without cutting branches is shaking (mahrak, miruug B.) with the shepherd’s crook (mahjan Ar., antiir B.). It is typically done, often by women or children, for small stock, especially for young weaning or weak animals and for sheep because they do not climb trees as goats do. It can be done throughout the year as long as trees are productive. Shaking and pruning trees to harvest fodder are ancient tending practices, depicted as early as the Egyptian New Kingdom (1539–1075 BCE; Andersen, 2012).

It seems reasonable to assume that pastoralists in the drylands bordering the Nile Valley practiced such techniques in ancient times. That the same tending practices are in use today suggests that rather than overusing their essential tree resources, local peoples long ago developed effective and sustainable techniques for conserving them. One conceivable way to proliferate the vital acacia tree is entirely absent among all the culture groups, viz. planting it, even though they possess detailed knowledge about seed dispersal, sprouting and regeneration (including the fact that successful regeneration is virtually impossible as several successive rains are needed). Some say simply, “God grows the tree.” The acacias’ importance is summarized by a middle-aged Ababda man: “We cannot live without sayaal [subsp. raddiana].