Encyclopedie , Flora of Israel, 23/02/2011,
Most acacia species found in Israel and neighboring countries are actually small to medium shrubs, not single trunk trees. There are some exceptions and those have trunks that range in diameter between 10cm and 30cmm. Perhaps the only large acacia tree species is Acacia pachyceras. In Wadi Ram in southern Jordan I once (~15 years ago) came across a sample of this species whose trunk diameter was near 100cm. Please note that this particular tree was very old, perhaps several hundred years old, so this figure is more like maximal value, not a minimum.