Paradoxically, forest-dependent rural communities in the tropics often have little experience of propagating trees, either from seed or from cuttings and this is the case in the Bolivian Amazon. As part of initiatives to enhance non-timber forest use through agroforestry and fruit tree production we sought the support of the innocent foundation to bring Kew horticulturalist, Carlos Magdalena to the Pando to provide hands-on training to three rural communities. Carlos is well known in Kew’s tropical nurseries as an expert in the propagation of challenging species, he is also a native Spanish-speaker and experienced in training. The aim of our training was to help communities propagate material of species for which they either can’t get enough seed e.g. Sinini (Annona muricata), whose seeds have low fertility such as acerola(Malpighia emarginata) or which take a year or more to germinate, such as the Brazil nut (Bertholletia excelsa).
Training covered key aspects of making cuttings, air-layering and grafting. For example, how to cut the stem to expose the maximum amount of cambium, the tissue from which new roots will grow? What part of a stem is best for preparing a cutting? How many leaves should remain on a cutting? And how to trim them if necessary. It then covered how to look after cuttings once established, including how to make a polytunnel from locally available materials. In total we worked with approximately 60 community members spread over a 300 km stretch of the Pando. At each community the needs and interests were slightly different, as were the facilities available and so we tried to tailor the training accordingly. We found considerable interest and enthusiasm amongst community members, which suggests that the limited capacity for tree propagation is not for lack of interest.
In addition to restoring soil fertility to abandoned slash-and-burn sites we are also working to use Inga to rehabilitate degraded pasture and severely degraded soils. Soils that have been heavily compacted by cattle over several years or by heavy machinery. Rehabilitating such sites, especially in the case of cattle pasture could have a significant impact in the region because adding value to such marginal land could help reduce the pressure on natural forest. With this aim we planted two such sites in March 2014. Revisiting the sites in July has shown mixed results with some of the seedlings doing very well (see image below) whilst others are clearly suffering (see image above). In comparison with slash-and-burn sites where we have lost very few seedlings, and most of those to overzealous weeding, Continue reading Inga establishment on heavily compacted degraded soils→
One of the aims of our work is to identify which species best support agroforest in the Amazon. There are well over 25 native Inga species in our study area. From our knowledge of these species elsewhere in South America we know that some are small-leaved or slow-growing species that would not be much use in soil rehabilitation whilst others do not respond well to pollarding. This leaves ten or so species that we would like to include in our experimental plots. The logistics of including additional species is, however, a challenge as trees produce fruit for a short period and when they do there is stiff competition for them from birds and monkeys. Also seed has to be planted within hours of being removed from the fruit. Continue reading Trialing a fourth agroforest species: Inga velutina→
Planting Inga trees in cattle pasture was undertaken as an experiment in order to evaluate its potential. It had not been done before in South America and although hopeful we did not know what to expect. As can be seen above, two months in, things are not looking so good for many of the seedlings which look stressed and not growing. This could be for several reasons: the ground is heavily compacted by cattle, they are in a very open site exposed to the sun or they have not had enough rain. Interestingly the slower-growing currently undescribed species of Inga that we trialled has fared significantly better and although it hasn’t grown appears to have settled in well. On seeing these images, Inga expert Terry Pennington remained quite optimistic and says that there is a good chance that they will recover and grow. Continue reading Enriched cattle pasture two months on….→
After much hard work by members of the San José and Palacio communities helped by Rolman Velarde and Rodrigo Flores we planted another two agroforest plots this April 2014. The seedlings were four months old and this entails a risk that they could be root-bound. They were also planted right at the end of the wet season and so will not benefit from a couple of months of rain to become established. We will be observing their progress with a lot of interest as due to poor weather earlier in the year and flooding at Palacio these plots have been plotted in suboptimal conditions. Their success or failure will provide us with important information on maximum seedling size for sowing and whether or not the dry season should be considered a barrier to planting out young plants.
As highlighted in previous posts we are aiming to engage with cattle ranchers and non-subsistence farmers as well as rural communities. The reason for doing so is that these larger-scale enterprises arguably have just as big an impact on natural forest as small scale slash-and-burn farmers. In March we planted our first Inga trial to enrich degraded cattle pasture at San Antonio cattle ranch and this April we have planted 2 ha of Inga on abandoned land at the Las Palmas farm. We also have another interested rancher, Ruben Burgos, and look forwards to planting on his ranch as soon as we have sufficient seedlings to do so. With respect to engagement we are using a different strategy with cattle ranchers and farmers than that which we developed to work with rural communities. Continue reading Additional cattle ranches and farms join our project→
It is now a month since sowing our first agroforest plot during the last days of February. A month later Rolman Velarde and Rodrigo Flores returned to assess how the seedlings were doing: how many had died, what evidence of pest damage there was and how they had grown. As you can see in the image above progress has been good. Whilst they may not have grown very quickly, none had died and only a few had suffered what looks like cricket damage despite most having aquired the protection of ants attracted to the nectary glands on their leaves. We were also reassured to see that ‘weeds’ have not grown up faster than anticipated which means that our plan to weed every two months should be effective. The wet-season is now starting to abate and in three months the driest time of year will test their establishment. Continue reading One month after planting…→
Forest Futures projectOn March 11 I gave a presentation to the Universidad Amazónica de Pando (UAP, Amazonian University of Pando) about our work whose aim is to return degraded land to productivity using Inga agroforest. Also the broader aims of our Forest Futures project too. I was very fortunate in having a good audience and several good questions. We hope to collaborate with the University’s Agroforestry module and involve students in undertaking some of the research on the mpacts of Inga agroforest that we do not have the resources to undertake. In addition the University is keen to establish a demonstration plot, so a very rewarding morning!
There are several reasons why it might be necessary to use transplanted seedlings for the establishment of agroforest plots. The most obvious one is that it avoids the planning and serendipity of obtaining seed from trees whose fruiting time can be hard to predict and whose seeds cannot be stored, or where parrots and monkeys find the fruit first. Often if appropriate Inga species can be found nearby then the chances are there will be a bank of seedlings also. Fortunately there are few predators of the seeds so even when the fruit have been eaten, the seeds will normally make it to the forest floor where many will germinate. Continue reading Evaluating the use of transplanted wild seedlings→
Despite the impact cattle-ranching has had on the Amazon over the past 40 years many ranchers are not making money. Degradation of the soils and quality of the pasture results in farms with very low densities of cattle spread over large areas that are expensive to maintain. There is also significant encroachment by inedible (to cattle) shrubs and grasses. This generates demand for fresh pasture which is in-turn leads to further deforestation. In addition, diversification away from beef to more profitable dairy relies on cattle breeds, such as Frisians, that are not well adapted to the heat of the tropics and suffer from the lack of shade in the colossal fields.