SOME RESULTS FROM SPECIES AND PROVENANCE TRIALS OF EUCALYPTUS SPECIES IN THE DEPARTMENT OF ANTIOQUIA, COLOMBIA ¹

by

BACKGROUND

Seven species/provenance trials were established at five altitudinal locations (0-2800m a.s.l.) in 1982 in the Department of Antioquia, Colombia. These trials included 82 provenances of 21 species and sub-species of the genus Eucalyptus. A description of the trial sites is given in Table 1.

The seed of the Australian species was procured from CSIRO, Australia. Additional seedlots were obtained through CTFT (France); the Chinese Academy of Forestry (China); CATIE (Costa Rica); Jari Florestal (Brazil); SETROPA Seed Company (Netherlands); and INDERENA, CVC and Cartón de Colombia (Colombia). A list of the seed sources is given in Table 2.

Field establishment of the trials was carried out between December 1981 and June 1982. The experimental design used was randomized complete blocks with 10-tree line-plots and 4 replications, except in the case of the provenance trial of E. urophylla, in which a Latin Square-design was applied (16-tree plots). Each block was surrounded by a l-tree buffer. Planting distance was generally 2.5 × 2.5 meters, except for on site 1 (2 × 2m).

The plots were regularly maintained and were fertilized at age 1 (NPK, 13:26:6, plus “Agrimins”, composed of N, P, Ca, Mg, S, Fe, B, Zn, Mo, Na, Cl).

Height of the trees was measured yearly, DBH has been measured since age 3. A score was given for stem form and observations were regularly made on phytosanitary condition of the trees. Information on statistical analysis and details regarding the measurements, are available from the authors.

RESULTS AND CONCLUSIONS

Overall survival of the five trials shows a tendency to increase with altitude, possibly due to lesser competition from weeds and lower air humidity, leading to lower incidence of disease. Sites 1 and 2 also had low soil fertility, contributing to low survival of the plants. On the other hand, low minimum temperatures at site 5 adversely affected many of the species/provenances at that test site.

At the two lower sites, survival ranged between 0 and 90%; on site 1, 24 treatments had a survival rate of less than 30%, while only 4 treatments reached such a low level on site 2. At the three higher sites, the majority of the treatments had a survival of more than 70% (up to 100%).

Height, diameter and volume of the trees at age 5, are given in Table 3.

Among those treatments with more than 70% survival, the best performance as regards height, diameter and volume, coupled with good stemform and little or no evidence of gommosis, was shown by E. tereticornis at sea level; E. urophylla at 1000 m a.s.l.; E. saligna, E. grandis and E. robusta at 2000 m a.s.l.; E. regnans at 2400 m a.s.l.; and E. nitens, E. regnans and E. viminalis at 2800 m a.s.l. Some promising provenances of a few other species were also identified for each site.

For the time being, results are considered reliable only for species on the sites lying between 2000 and 2400 m a.s.l.

REFERENCES

SOCIEDAD FORESTAL DE ANTIOQUIA-CORFORESTAL. 1985 Inventario de bosques artificiales. Departamento de Antioquia. Tomo II. Medellín, Corforestal, 1985, 57 p. + anexos.

VELEZ MESA, José Gerardo. 1982 Indice de sitio, su estimación adáfica y rendimiento del Eucalyptus saligna en Antioquia. Tesis Ing. Forestal. Medellín, Universidad Nacional de Colombia, 1982, 142 p.

Table 1. Geographical, climatic and edafic conditions of the trial sites (Department of Antioquia, Colombia).

TABLE 2. GEOGRAPHICAL ORIGIN AND CLIMATIC DATA FOR THE PROVENANCES INCLUDED IN TRIALS ON 5 SITES IN THE DEPARTMENT OF ANTIOQUIA, COLOMBIA

Abbreviations: NSW= New South Wales;
NT=Northern Territory;
Qld=Queensland;
Tas.=Tasmania;
Vic.=Victoria;
WA=Western Australia.

TABLE 3. RESULTS FROM EUCALYPTUS SPECIES/PROVENANCE TRIALS ESTABLISHED ON 5 SITES IN THE DEPARTMENT OF ANTIOQUIA, COLOMBIA, AT AGE 5 YEARS

N.B. Plots in which survival was less than 30%, were not considered (marked - ).

¹ Abridged version of manuscript received August 1989.