``Ninnau heb ysgog acheb
ynom chwyth barlyswyd enyd.''
Features they share with the southern Saharan vegetation include the growth after rainfall of characteristic communities of annual plants in depressions between dunes (acheb
) in sandy deserts, the presence of different species of Acacia and Prosopis (A.
Some annual species have a very short life cycle, two weeks or less, and make up the acheb
of the northern Sahara and ghizzu of the southern Sahara.