In previous posts we have delved in the cultivation of poplars in Italy and France. Now is Spain’s turn. The cultivation of poplars (genus Populus) in Spain has been extensively developed and has experienced significant growth in recent decades. The country has a National Catalog of basic materials for the production of forest reproductive materials, which includes the poplar varieties used in Spanish territory. These cultivars have been carefully selected for their adaptation to different soil types, altitudes, and resistance to pathogens, aiming for sustainable and profitable cultivation.
In the National Catalog, there are different species and hybrids of poplars, each with its particular characteristics. Among them, the cultivars of the species Populus nigra, Populus deltoides, Populus x euramericana, Populus trichocarpa, and Populus x interamericana stand out. Each of these cultivars possesses specific qualities and is better adapted to certain types of soil and environmental conditions.
Species and hybrids in the national catalog
The National Catalog of basic materials for the production of forest reproductive materials of the genus Populus in Spain includes the following poplar cultivars:
- Populus nigra (European Black Poplars): These trees are hardy, with often twisted and short trunks. They have a blackish and rough bark with excrescences. Their leaves are small and leathery, with globose and dense capsules.
- Populus deltoides (American Black Poplars): They are trees with straight trunks and rough bark showing large ribs. Their leaves are large and triangular, and the branches thick and slightly horizontal.
- Populus x euramericana (Euramerican Poplars): These are hybrids between Populus deltoides and Populus nigra. They are adapted to alluvial soils with a shallow water table.
- Populus trichocarpa (Balsam Poplars): These trees have straight and cylindrical trunks with leaves longer than the previous species. They are resistant and tolerant of shallow soils.
- Populus x interamericana (Interamerican Poplars): These are hybrids between Populus deltoides and Populus trichocarpa. They adapt to different environments, from alluvial soils to those without a water table.
- Populus deltoides x Populus alba: This group includes a single clone, which is currently considered a Euramerican hybrid.
Selection of cultivars for poplar plantations
One of the fundamental choices when establishing poplar plantations is the proper selection of the genotype or genotypes to be used, considering their adaptability to a specific type of soil, altitude, and disease resistance. Likewise, consideration must be given to the final use of the wood, especially its peeling, which represents one of the main attributes of poplar wood.
The basic criteria for selecting suitable cultivars are as follows:
- Productivity: Poplar varieties with significant growth and high yield for wood production are sought.
- Resistance/tolerance to pests and diseases: It is essential that the selected cultivars be resistant to common pathogens.
- Wood quality: The cultivars should produce high-quality wood for industrial use.
- Ease of reproduction and pruning: The preferred poplar varieties are those with good structure, ease of pruning, and rooting capability.
Research and Genetic Improvement
To promote sustainable cultivation and genetic improvement of poplars, trials with different cultivars are carried out in various regions of Spain. These trials are conducted by companies such as Bosques y Ríos in collaboration with major European Research Centers involved in the genetic improvement of poplars. Genetic diversity is a key factor in dealing with pests and diseases, and continuous efforts are made to improve and adapt the cultivars to local conditions.
In conclusion, poplar cultivation in Spain has experienced remarkable progress in recent years thanks to the selection and use of suitable cultivars for different soil and climate conditions. Genetic improvement and constant research lead to more resilient and productive trees, contributing to sustainable and profitable poplar cultivation in the country.