Five Year Growth and Survival of Eucalyptus Hybrid Clones in Coastal Kenya
Abstract: Twelve eucalyptus
hybrid clones (6 grandis-camaldulensis i.e. GC and 3 grandis-urophylla i.e. GU
hybrids) and 3 local landraces (E. camaldulensis, E. tereticornis, and E.
urophylla) were established in Gede, Sokoke, and Msambweni in the Coast
Province of Kenya in 2002, to compare growth, survival, and adaptability in the
3 sites. By the end of the 1st year,
trees in Sokoke were more than 3 times the mean height of those in Gede and Msambweni.
However, these growth advantages during the 1st year in Sokoke were not
maintained and by year 2 Gede had caught up, although Msambweni still lagged
behind. By age 5 there were significant growth differences between clones. Of
the tree sites, Msambweni had the lowest tree growth. GC167, GC14, GC581, and GC584 proved
themselves as the better clones, while E. camaldulensis and E. urophylla were
the better local land races. Overall, the “local land races” performed poorly
in all sites. Survivals were over 80% in
all sites for the best performing clones. However, in Sokoke, 1 clone died
(GU7) while another (GU8) had a survival of less than 20%, while EC and ET had
survivals less than 35%. GC796 died in Msambweni and had 8% survival at Gede.
The poor survivals in Sokoke may have been due to a severe drought in the 3rd
year. The initial outstanding growth
performance in Sokoke may have been due to the fact that Sokoke was a ‘virgin’
forest site and presumably more fertile than the other two sites. These results
show that recommendations on outstanding clones or new germplasm for planting
or sale to farmers are best done at the end of the rotation for a
particular intended product or use.
Author: Balozi B Kirongo,
Kimani GK, Kingiri Senelwa, Lazare Etiegni, Angela Mbelase, and
Mbae Muchiri
Journal Code: jpkehutanangg100004
