Using trees as a symbol of peace is in keeping with a widespread African tradition. For example, the elders of the Kikuyu carried a staff from the thigi tree that, when placed between two disputing sides, caused them to stop fighting and seek reconciliation. Many communities in Africa have these traditions.

For example, they have land. The government of Qatar wants to lease the Tana River delta, which is in Kenya, from the Kenyan government, so that they can produce food there. People in Kenya need food. We have people who have studied agriculture. Why is it that if we really need food, we cannot go into the delta and develop our own food?

It gradually became clear that the Green Belt Movement's work with communities to repair the degraded environment could not be done effectively without participants embracing a set of core spiritual values.

The government of Qatar, as I mentioned, has proposed to come and lease Kenya's Tana River delta in order to farm there. What I am not sure of is, has an environmental impact assessment been made to ensure that exploiting this delta for agricultural activities is the best way we can use the delta?We must be concerned about the long-term impact of agricultural activities in the delta.

People are dynamic. They change, and soon as there are enough of you, things change [for a whole society].

There are certain areas where foreign investors can help the local people to generate wealth, and improve their quality of life. Some companies, for example, Del Monte, which produces pineapples in Kenya, pay a huge amount of taxes, I am sure, to the Kenyan government, and they do create jobs for thousands of locals.

One of the reasons why I say we all need to work together to save the Congo forest, because if we don't save the Congo forest, the Amazon forest and the southeast Asia forest, if those forests release the carbon they are trapping at the moment, much of what you will be doing in the North will be negated by the amount of carbon released into the atmosphere.