THE LIVINGAGRO INNOVATIONS CATALOGUE FOR GREEK AGROFORESTRY

Having identified potentially useful innovations, the partners of LIVINGAGRO project developed a dedicated Catalogue intended to provide an overview of some of the innovations that may be useful to stakeholders involved with multifunctional olive systems and grazed woodlands, in order to help bring together economic stakeholders and innovators who may be able to collaborate to solve common problems. This activity included assessing the stage of readiness of a potential innovation, as well as which type of challenges it addresses. Taking into consideration the needs expressed by stakeholders, the research team of the Mediterranean Agronomic Institute of Chania (MAICh) and the technical team reviewed the information provided. Following this review, the working group went back to the innovators to address questions and fill in gaps, then incorporated the responses into the innovation descriptions.

Introduction to Section 2 of the Catalogue concerning intercropping and preparation for climate change in olive groves

Traditionally, olive groves in Greece have included plants such as legumes, cereals, herbs, vegetables, walnuts, grapevines, and truffles. Such a combination of two crops grown at once on a plot of land is known as intercropping. When it includes trees and an annual crop, it is also a type of agroforestry. The traditional agroforestry practice of intercropping offers many benefits over a monoculture--benefits for the soil, the farm, the broader environment, and (as a result) the farmer. Recommending that olive farmers consider innovating by adapting new, improved versions of traditional agroforestry practices, numerous scientists now provide specific advice to help farmers achieve the greatest possible benefits.

Intercropping increases olive groves’ sustainability by adding to their biodiversity and stabilizing the soil, thus reducing trees’ vulnerability to pests, diseases, and climatic stresses. The greater diversity in plant life enables a larger variety of organisms in the soil, as well as more beneficial insects, pollinators, and birds. With intercropping, the soil benefits from increased porosity, improved drainage, less erosion, and decreased nitrogen and phosphorus leaching, which means fewer valuable minerals lost and less pollution of groundwater and surface water. Fewer pesticides and nitrogen fertilizers are required, and olive trees tend to be healthier, which benefits the planet and the farmer. In addition to saving money on pesticides and fertilizer, farmers may also benefit financially both by producing higher quality olives and by harvesting a second crop. They can either sell this product (as in the case of the recently popular avocados) or use it as a natural soil enricher or an animal feed (as with legumes).

One of the most important crops for the Mediterranean region, the olive tree will be subject to increasingly harsh abiotic stresses due to climate change in the coming years. Abiotic stress comes from environmental conditions that can harm plants and reduce their growth and yield, such as extreme temperatures, soil salinity, and drought. (Biotic stress, on the other hand, is caused by living things such as insects, weeds, bacteria, viruses, or fungi.) Shifting cultivation zones, depletion of organic matter, desertification, degradation of water resources, and other challenges make it imperative to prepare for the future, for example by intercropping and by using trees that can resist the effects of climate change.

Presentation of Innovation 8: olive tree-avocado intercropping

Background

Intercropping with a crop such as avocados can offer many benefits for both the environment and farmers, including a significant financial advantage, given the high selling price of avocados. While olive trees used to be co-cultivated with various other trees, this has become less common, leading to many negative effects for both the olive groves and the rest of the ecosystem. The most obvious example in Greece is a serious problem with the olive fly and the widespread use of pesticides to combat it. As a solution, farmers can once again introduce more biodiversity into the rural ecosystem, for example by planting avocado trees between widely-spaced olive trees. In addition to making it easier for the natural enemies of pests to thrive and help prevent pest outbreaks, this practice will significantly boost farmers' income.

Keywords

Olive tree, olive farming, Koroneiki, Hass avocado, Reed avocado, Lamb Hass avocado, avocados, intercropping, agroforestry, carbon storage, biennial bearing

Methodology

In an olive grove with Koroneiki variety olive trees planted 7*7 or more (that is, with at least 7 meters between each row, and at least 7 meters between each tree in a row), we plant avocado trees (Hass, Lamb Hass, or Reed variety, plus Bacon variety as a pollinator) half way between each pair of olive trees in a row to create a 3,5*7 planting system. We leave 7 meters free between rows for farm machinery, vehicles, and plenty of exposure to sunlight (since both types of trees need a lot of light). In order to maximize the likelihood of avocado pollination, we need to plant Bacon variety avocado trees in specific places.

Specifications

Appropriate pruning is essential so all the plants receive adequate exposure to sunlight. There are two main pruning periods for all the plants, the first at harvest time, the second in early summer. There must also be two irrigation systems (one for each kind of tree), because these trees have different irrigation and fertilization needs. 

Impact

This type of intercropping can increase farmers’ income. It also benefits the environment, as it decreases erosion while enabling higher carbon storage. It creates a better microclimate and an improved habitat for many animals, birds, insects, etc., increasing biodiversity so that less pesticide is likely to be needed.

Filled gaps

By increasing overall fruit production, this sustainable type of intercropping can help compensate for olive farmers’ low income due to climate change, biennial bearing, high production costs, and low olive and olive oil selling prices.

Limitation

A specialist should evaluate the grove’s location, water, and soil to see if appropriate conditions exist for this type of intercropping to succeed. Additionally, there must be an adequate water supply. Pruning knowledge is essential, since shade affects the production of avocados and olives.

Next steps/potential extension

Intercropping with nitrogen fixing plants in addition to avocados is recommended in order to enrich the soil microbiome, increase its fertility (especially in terms of nitrogen), increase biodiversity, and lower costs. This could reverse soil degradation while producing higher quality fruits.

Find out more

Spiros Lionakis, PhD
Emeritus Professor of Arboriculture
Hellenic Mediterranean University
slionakis@hmu.gr

  LINK TO THE COMPLETE GREEK INNOVATIONS CATALOGUE (EN)

In the next Episode we will deepen and explore innovation 9 related to grafted olive trees resistant to the effects of climate change

In parallel, we will start to introduce additional LIVIGAGRO innovations identified for the Lebanese and Jordan multifunctional olive systems context, stay tuned...