Well, we didn’t write the whole book, but two chapters šŸ™‚ In 2015 we went to Chiang Mai University in Thailand, to the Forest Restoration Research Unit, and participated in a workshop ahead of its time: Automated Forest Restoration. Can Robots Revive Forests?

We shared for a week with ecologists, biologists, NGOs and engineers from all over the world, trying to answer this question, and as a result of this meeting, after years of editions and revisions, the book has finally been published on the occasion of the Reforestation for Biodiversity, Carbon Capture and Livelihoods conference. You can see in this video the presentation of the book:

You can download the book for free, with advanced content, from species identification with satellite imagery, aerial planting with drones, to locating wildlife from the air.

News from the Alpujarra Forest Seed Laboratory

Spring has come early this year. February is usually the coldest month in the Alpujarra, but this year we wore short sleeves as we gazed at the snow-capped peaks of MulhacƩn.

Despite this, we have been locked up in the laboratory, involved in the thousand and one experiments we need to do to master direct sowing.

peletization process

We are focusing on pelleting. We have chosen wheat seed to carry out the trials because, as well as being very economical, it germinates quickly at low temperatures. We have coated the wheat with different types of clay, biochar, compost, sawdust, amalgamating it with arabic gum. These are preliminary tests to obtain the ranges of quantities and necessary characteristics of these materials, observing how each ball reacts and germinates after drying. This month we can highlight the following observations:

  • Biochar has difficulty binding to the ball if it has a particle size greater than 0.6 mm.
  • For the same amount of gum arabic, the hardness of the ball increases with the size of the ball.
  • For seeds that swell as they hydrate, it is possible to design the formula so that the materials are cracked when germination begins. This increases aeration and speed of germination.
  • The ball can have a clay finish to reduce dust, and as a water retainer. Bentonite and kaolin shrink a lot when drying, breaking the balls. Red potter’s clay works well.
  • The powder of each material must be well dried so that it sticks well to the ball during the pelleting process.

These preliminary tests are also being used to adjust and improve our seed coating machine. In the initial design, the liquid is sprayed by means of a venturi effect with compressed air. But the impact of the pressurised air on the seeds is leading us to redesign the system.

sowing seedballs


We have completed trials that started in June 2020 with Escaramujo or Rose Hips (rosa canina). Rose hip seed has a combination of three dormancies: physical, which prevents water from entering the interior of the seed; morphological, the seed detaches from the plant without having completed the internal development of the seed; physiological, the seed needs cold to initiate germination. To obtain an adequate germination protocol we did several trials with different types of substrate and different times of hot and cold stratification. We need to carry out a new batch of trials to reach the optimum which, based on the results obtained, we expect to be in the following conditions:

  • the use of black peat favours germination.
  • two months of warm stratification is sufficient to eliminate morphological dormancy.
  • hydration/drying cycles during warm stratification do not introduce significant benefits in the final germination %.
  • The optimum cold stratification period should be between 3.5 and 4.5 months.

escaramujo seedlings


We have conducted several germination tests on seeds that were primed months ago. The storage of primed forest seeds is not well studied by science and we have found that the benefits of priming start to be lost after 3 months of storage. These losses are highly variable from one species to another and depend on the type of priming treatment. Until academia improves the way priming is done for long storage periods, this point is the major drawback in forest seed sowing with priming.

Germinating seeds of fresno, enebro y retama

The priming of the strawberry tree (arbutus unedo) and fresno (fraxinus angustifolia) has become more dominant. The trials started in autumn 2020 and during February we observed the germination of the different treatments carried out. We can conclude that both species perform well for hydropriming treatments, although the factors involved in obtaining an optimum are wide-ranging, and we are still searching for them. 

The priming of Retama (retama sphaerocarpa) is also almost solved. Of the 9 treatments observed, almost all introduce benefits. The one shown in the graph is the best we obtained. To the known benefits of priming, we can add a reduced willingness to develop fungus during germination. These priming treatments were carried out using the aerated soaking method, as this allows large quantities of seeds to be treated.

New Podcast: Seeds and Drones

Querƭamos darle un nuevo formato mƔs audiovisual a estas noticias mensuales, y quƩ mejor que un programa de Podcast!
Lo hemos llamado Semillas y Drones, gracias a Andreu IbaƱez de lleidadrone por poner el empeƱo. Cada mes publicaremos un programa en vĆ­deo (youtube) y audio (anchorfm) donde comentaremos las novedades de este mundo de la reforestaciĆ³n con drones, una gran oportunidad para hacer frente a la crisis climĆ”tica.

We wanted to give a new audiovisual format to this monthly news, and what better than a Podcast programme!
We have called it Semillas y Drones, thanks to Andreu IbaƱez from lleidadrone for putting the effort. Each month we will publish a video (youtube) and audio (anchorfm) program where we will comment on the latest news in the world of reforestation with drones, a great opportunity to tackle the climate crisis. (In Spanish)

We have a new Patreon!

Sometimes we have doubts about whether what we do makes sense, how to keep the project active financially, how to finance the research and publish the results openly, helping other projectsā€¦ If suddenly a new person arrives on Patreon who decides to support us on a monthly basis, all the nonsense suddenly goes away. Thanks Peter!