East African Agriculture and Forestry Research Organization, 1969.
E. Mortenson
INTRODUCTION
Starting at the beginning of the century plantations of several exotic softwood and eucalypt species were established in East Africa. The four main coniferous species introduced into the moist highland areas were Cupressus lusitanica, Cupressus macrocarpa, Pinus patula and Pinus radiata. Serious diseases occurring in these species as well as unsatisfactory results from some wood quality studies in pines have, however, given cause for anxiety. In addition new areas, such as the coastal areas of East Africa and the lakeshore areas in Uganda, are being evaluated and large scale investment and development are envisaged. The state of knowledge on the species and establishment techniques to be used on these sites is unsatisfactory, and unless research is conducted into these problems there is a serious danger that the projected development may be a failure. It is quite obvious that the majority of provenances introduced into East Africa are of haphazard origin, and as a matter of fact most of them have been introduced, not directly, but through South Africa, Australia and New Zealand.
These problems were brought to the attention of the East African forest authorities and research plans to avoid failure were proposed. An application for financial assistance forwarded to the Norwegian Agency for International Development was positively received, and funds were made available for a seed collecting expedition to Mexico and Central America. E. Mortenson was appointed Research Officer of the expedition which lasted from 14th June 1968 to 19th April 1969. FAO contributed with a travel grant to Patrick Tesha of the Tanzanian Forest Department. Tesha assisted Mortenson in Mexico and Central America during the period August – December 1968.
OBJECTIVES
Collection of seeds for alternative species in East African plantations, possessing greater pest resistance, better wood quality and higher economic value than the species presently used.
WORK DONE
CUBA
Seed collection of Pinus caribaea var. caribaea and P. tropicalis is carried out by Government employees. Provenance trials of Pinus caribaea have been started and seed orchards have been established to meet the existing need for 80–90 million plants per annum. It is probable that large quantities of seed of P. caribaea var. caribaea from Cuba will be available within the next four or five years, when the ambitious Cuban plantation programme will be tapering off.
GUATEMALA
Most of the pine species found in Guatemala occur in the moist highland areas between the Mexican border and Guatemala City. Pinus oocarpa was collected from the central parts of the country, where a rather continental climate with fairly high temperatures prevails. Cones were collected in Baja Verapaz and Zacapa. In Sierra de las Minas in Zacapa P. oocarpa forests extend down to only 100 m above sea level. In Jalapa, which is an interesting area from the climatic point of view (prolonged hot dry season), only poor stands were found and no collection was made.
Pinus caribaea var. hondurensis was collected at Poptún and Dolores in the department of Petén, in a pine grassland savanna area approximately 450 m above sea level. The climate is warm and moist with the dry season extending from December to April or May. Yearly precipitation ranges from 2 000 to 2 500 mm. The soils are clay soils (0.5 – 1.0 m) overlying limestone rocks. A seed production area of about 10 ha was selected and thinned in co-operation with and for the FAO/FYDEP (Fomento y Desarrollo del Petén).
Guatemala will probably be the best area for seed procurement for East Africa in the years to come. The climate is fairly hot and dry, Pinus oocarpa and P. caribaea grow at low altitudes, and they have a good stem form. Seed collection can probably be arranged through sawmill owners and other locals.
HONDURAS
The inland regions of Honduras (the Quimistan area) were visited, but no Pinus caribaea seed was collected because of the poor phenotype of the trees. In the Guaimaca area north of Tegucigalpa (the Department of San Francisco Morazan, close to the border with Olancho) substantial forest exploitation is going on, and extensive collection of seed from felled trees has been undertaken. The species is probably Pinus oocarpa var. ochoterenai, and the quality of the trees is high, although there is tremendous variation both within and between the stands. The P. oocarpa stands at Orica were also visited and were found to be of the same high quality as those at Guaimaca. Despite the fact that there is a sawmill operating in Orica it was decided to buy seed only from the technician in charge of the Guaimaca area, as the sawmill owners in Orica were completely occupied in keeping the mill running. Additional Pinus oocarpa forests along the road between San Pedro Sula and Tegucigalpa were also visited. The quality of the stands seemed to be good but they are not of as high a standard as those visited earlier. South of Tegucigalpa there appears to be tremendous morphological variability in the stands.
In the future collection of Pinus oocarpa from the Departamentos San FranciscoMorazan and Olancho will probably be most important. It is possible that a big integrated pulp and papermill will be in operation in Olancho by 1972. As soon as the road system is improved the area will have a great potential for seed production. The stands are of such high quality that seed from general bulk collections from felled trees can safely be accepted.
NICARAGUA
Nicaragua is a low-lying tropical country where the pines reach their southernmost distribution in the Western Hemisphere (Pinus caribaea var. hondurensis 12°North, Pinus oocarpa 13° North). Pinus pseudostrobus is also found in the country. The Pinus caribaea forests extending from Bluefields northwards to the Honduran border at Río Coco (700 000 ha) belong to the most tropical pine provenance in Central America. The pines grow on very infertile soil, the yearly precipitation is approximately 3 600 mm, and the temperatures fluctuate between 20° and 30° C.
Most of the mature pines on the coastal plain have been cut and serious restrictions on sawmilling have become necessary. Fire protection measures are also being imposed. A total area of approximately 50 000 ha is under protection. The main area for Pinus oocarpa extends from the Matagalpa area northwards. Some stands approximately 900 m above sea level were visited, but the trees left standing after some heavy cuttings were found to be of very poor quality.
Organizing seed collection in Nicaragua is difficult as the remaining closed stands of mature trees are very hard to reach. An additional difficulty is caused by the very high rainfall which complicates seed extraction. The irregular times for opening of the cones also present problems: the normal seed collection time in Puerto Cabezas and the Waspan area is between April and June. However, in 1968 the cones opened two months earlier.
COSTA RICA
The Instituto Interamericano de Ciencias Agrícolas at Turrialba was visited and wood property problems were discussed. In Costa Rica the main emphasis of the research work has been on hardwoods. These are probably only of minor interest to East Africa, as they have adapted themselves to the comparatively humid Central American climate. The pines in the productive highland areas of Costa Rica were disappointing. Pinus caribaea, P. taiwanensis and P. patula were rather unimpressive, Araucaria cunninghamii and A. hunsteinii looked more promising. The most promising species in these areas seemed to be Cupressus lusitanica and Alnus jorullensis, although much better Cupressus lusitanica stands can be found in East Africa. Species trials, mainly of Eucalyptus have been established on the comparatively arid Pacific Coast.
MEXICO
Of the approximately 100 pine species occurring throughout the world one third are native to Mexico.
Flowering and seed production are irregular, and a lot of basic research still remains to be done. About five years would probably be needed to make worthwhile collections of all pine species of interest to Mexico. Seed collection is further complicated by the complex nature of land ownership and by the fact that many of the accessible areas have been heavily exploited.
Before collections were started a permit was obtained from the Secretaria de Agricultura y Ganadería. Half of the seed collected was given to Mexican forest authorities.
Because of the size of the country seed collection was restricted to the central and southern parts. Available information on the climatic conditions indicates that seed from these areas might be suitable for East African conditions. Several states were visited in order to locate good stands.
The State of Jalisco is known for its high-quality stands of Pinus douglasiana. Unfortunately it was an extremely poor seed year and no seed could be collected. There is, however, a possibility of obtaining P. douglasiana seed in the future from the Atenquiqe Paper Company.
In the State of Michoacan, one of the main forest states in Mexico, seed of Pinus oocarpa, P. leiophylla, P. michoacana, P. pseudostrobus, P. tenuifolia and Abies religiosa was collected in spite of the poor seed crop.
In the state of Mexico extensive collections of high-quality Pinus montezumae and P. leiophylla were made. Seed of Pinus tenuifolia was collected in the Valle de Bravo area where the trees reach heights of up to 50 m. Seed of Pinus lawsoni, Pinus pringlei and P. teocote was also collected. At Agua Bendita a collection was made of Abies religiosa.
In the state of Oaxaca a large number of pines occur naturally. At high altitudes P. patula grows in mixed stands with P. ayacahuite, at low altitudes with P. tenuifolia and P. strobus var. oaxacana. The last mentioned species is one of the main forest forming species in Oaxaca, and seed was collected from some trees of high quality. Because of the small seed crop of Pinus patula no collection was made, but it will probably be possible to get seed of this species through the Tuxtepect Paper Company. A collection of Pinus leiophylla, was made in Ixtlan de Juarez.
In the southernmost state of Mexico, Chiapas, seed of Pinus strobus var. chiapensis, P. oocarpa var. ochoterenai and P. oocarpa was collected. A collection of high-altitude Pinus oocarpa var. ochoterenai and Pinus pseudostrobus var. oaxacana was made at San Cristobal de las Casas. P. oocarpa seed was collected at Comitan. Extensive travel was undertaken in the forest area northeast of Comitan, where the forests at high altitudes are mainly a mixture of P. tenuifolia and P. ayacahuite. As 1968 was a bad seed year no collection was made, but it is hoped that seed will be obtained later through Maderas de Comitan.
QUANTITIES OF SEED COLLECTED
During the seed collection expedition to Mexico and Central America a total amount of 323 kg seed was collected. Eighty-four provenances of pines, four of Abies religiosa and one of Cupressus lusitanica were obtained. The expenses amounted to approximately $ 61 per kg seed. A further 62 kg of seed of P. oocarpa var. ochoterenai has been bought from Guatemala. The most useful species introduced into East Africa will probably be Pinus oocarpa var. ochoterenai, which should cover the whole ecological range from P. patula to P. caribaea.
