We advance in the number of crops with probes and sensors, the Paulownias in Spain. We will value the controlled irrigation and the influence on its growth in addition to the great savings of water and energy.
The Paulownias in Spain or Kiri
Paulownias in Spain or Kiri, which in Japanese means life, are a recent novelty, but the characteristics of their wood, their large contribution of biomass, and their rapid growth make farmers decide to cultivate them, provided that the characteristics of the terrain and climate are favourable.
Currently we can already find Paulownias in the Community of Valencia, Andalusia, Castilla la Mancha, Catalonia, Aragon, Castilla y León, Murcia and Extremadura. Slightly throughout the northern area.
They are trees from China and considered invaders. For this reason it must have a controlled production.
Some 17 varieties are known, but the most abundant are:
- Eloganta. It grows very quickly and adapts very well to the Mediterranean climate. It reaches heights of about 20 meters.
- Fortunei. A very rapid growth and higher than the previous one, about 30 meters. It needs heat and irrigation especially in the first two years.
- Stormy. It is more resistant to cold and has a much larger crown than the previous ones. It reaches about 15 or 20 meters in height.
- Kawakamii. Fast growth and a lot of crown.
All varieties have many flowers and are very aromatic. If the tree is considered ornamental, in gardens, to obtain more flowers it is necessary to prune in winter.
In four or five years we can already get the most out of this tree, which has multiple applications.
Once cut down, it reproduces again, even more strongly, because its roots are already developed.
Cultivation of Paulownias in Spain
To grow Paulownias we need a shallow soil with a sandy-loam mixture, well tilled and the possibility of installing irrigation, preferably drip, if we do not have rain in spring and some in summer. Usual risk in the cultivation of Paulownias in Spain.
- In the first season of growth it needs a significant supply of water, because the root system is small and due to evaporation it will need humidity with frequent watering.
- As its roots grow, we can space the risks because they gain depth. Once the roots are developed, they are resistant, this favors absorption and therefore the tree becomes leafy.
- The soil must be well aerated, its roots need oxygen and a very silty or clayey soil harms them. If the humidity is not controlled, the plantation will need furrows or ridges that drain the water, especially if it does not have a proportion of sand.
- The climate must be free of spring frosts. In the northern area there are some plantations in areas protected from frost.
Control with sensors and probes
- The ideal solution is to control humidity with sensors that indicate the need for water in real time.
- We must measure conductivity to avoid with its control the accumulation of salts, to which it is highly sensitive.
- The soil temperature sensor allows us to assess root health, so important for adequate nutrient absorption. Slurry and manure are suitable for it because its growth is so high that it needs a high nutrient content in the soil.
- Control the amount of irrigation water and possible breakdowns with a caudalimetro adapted to all types of hoses.
- Install a weather station that controls rainfall, relative humidity and outdoor temperature.
All of this agricultural sensor technology is wireless and provides data in real time. We have controlled cultivation throughout its phenological stage.
Paulownia Applications
One of the most important applications is for biomass. We can use the whole tree or just the pruning, the branches that we discard from the trunk and the leaves.
Biomass is organic matter used as an energy source.
The process consists of grinding the wood and letting it dry. Then compact it as much as possible, so that the caloric contribution is greater in the combustion.
The Paulownia is an ornamental tree that provides a lot of shade and its flowers are large and very decorative.
The leaves are used for livestock feed and the flowers for cosmetics.
One of the most important applications is what favors the environment, because its large leaves and rapid growth make it release large amounts of oxygen and capture a high percentage of CO2.
Usos de la madera de Paulownias
Another important application is for joinery and carpentry. The wood is hard and fire resistant, as well as light and straight in shape and without knots.
We can find it in house structures, in furniture, parquet floors and a long etc…
It is resistant to fire and possible termite attacks.
It does not absorb water, which makes it highly valued for outdoor use.
Another reason to plant Paulownias in Spain is because they favor the environment. Its large leaves consume large amounts of CO2 and increase that of O2.
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