Grevillea robusta is a well-known shade tree, used in coffee and tea plantations in East Africa since the early part of the 20th century. While it originates from Australia, it was brought over from India and Sri Lanka by European settlers. Smallholder farmers in the highlands of Kenya noted that there was little or no competition between grevillea and neighbouring crops. Indeed this is one of the reasons it was so successful as a shade tree amongst plantation crops. Responding to the local lack of timber and firewood, due to the expansion of farmland into previously forested areas smallholder took to planting grevillea, especially as a boundary tree from the 1970s onwards. While the immediate effect of grevillea planting was to satisfy those needs for wood, the tree also helps in various ways to conserve land and improve the soil. This too was probably a reason for its spontaneous spread.
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Where the Land is Greener