This is known as genetic control, a field the Forest Health Centre is currently engaged in. As the country continues to count its losses before a remedy is found, the public is being asked to replace cypress with other species not susceptible to aphid attack. Kenya's wealth of trees offers many choices. It does well above 1,200mm, prefers deep well drained soils, tolerates loamy-clay and is drought resistant once established. It makes a thorny evergreen hedge, usually 3-5m high and has grey bark and strong thorns some as long as 6cm.
Leaves are thin, shiny and dark green with rounded or notched tips.
Kei-apple also acts as a wind and fire break. It forms a very thick, strong fence and has no serious pathological problems. This is an indigenous shrub acacia widespread in all the arid areas of Kenya. It has distinctive small, grey hooked pairs of pickles with black tips. It is used as a live fence.