Arundo donax L. (Poaceae) is considered to be one of the worst invasive plants in the world, and here, we present a synthesis of all aspects of its biology, ecology and management that are relevant to understanding its invasive behaviour. This report presents information on the taxonomy, morphology, distribution, history of introduction and spread, ecology, responses to abiotic and biotic factors, biology, negative impacts, management and uses within the framework of a series of Botany Letters on Monographs on invasive plants in Europe. Arundo donax (giant reed) originated in subtropical Asia and is invasive in other warm regions worldwide, especially in degraded riparian areas. Introduced for use in agriculture, erosion control and construction in the Mediterranean European region since ancient times, it has become naturalized in several freshwater habitats and in disturbed areas. In its introduced range, A. donax shows strong genetic uniformity and no seed production. This situation is reversed in Asia, where this taxon is fertile and morphologically and genetically polymorphic. This perennial grass combines rhizomatous clonal growth with a tolerance to a wide variety of ecological conditions, such as high salinity levels and long droughts. This tall reed can increase the risk of fire, alter the natural drainage of channels and invade very sensitive habitats, posing a serious threat to riparian habitats and freshwater ecosystems. Effective methods to control A. donax are tarps on a cleared giant reed field to completely cover the affected zone, rhizome removal using a modified backhoe bucket adapted to separate soil from the rhizomes, and herbicide application on leaves. The combined technique of herbicide treatment plus stem-cutting can be included in management programmes, and this technique needs to be monitored over the long term to assess its success and to ensure native species colonization and ecosystem recovery. Regarding biological control, A. donax is host to different insect species that have been released to control it in parts of its non-native range (North America) with some success. However, these different methods of control should continue to be studied, evaluating the risks posed to the environment and the control level achieved. In this context, scientific, political and administrative efforts as well as environmental education are effective assets to address the management of this invasive species.

Chlorophyll fluorescence analysis (CFA) has been successfully used to rapidly determine the responses of different plants to herbicides. It has not, however, been used to test the effect of these products on invasive riparian species. This paper reports the use of CFA to determine photosynthetic activity in Arundo donax, an invasive reed causing serious problems in Mediterranean riparian habitats, in response to systemic herbicide application following cutting. Growth was measured in terms of new sprout relative height and sprout and rhizome relative biomass. CFA showed glyphosate, from half the on-label dose of 5 L ai.ha⁻¹upwards, to have a significant effect (100% reduction) on photosynthetic activity at 21 days after treatment (DAT), while profoxydim, from half the on-label dose of 0.375 L ai.ha⁻¹upwards, caused a 70% reduction soon after application, although these plants later recovered. Azimsulfuron, cyhalofop-butyl and penoxsulam had no significant effect on photosynthetic activity at any dose. At 60 DAT, glyphosate (from half the on-label dose of 5 L ai.ha⁻¹upwards) was associated with a 90% reduction in sprout height, while profoxydim (from half the on-label dose of 0.375 L ai.ha⁻¹upwards) caused a 50% reduction. No dose (0–2x the on-label dose) of azimsulfuron, penoxsulam or cyhalofop-butyl was associated with any significant growth reduction at 60 DAT. The results show that CFA can be used to successfully measure the response of these invasive plants to herbicides, and that glyphosate, and possibly profoxydim, might be used to control Arundo donax after initial cutting.

Jiménez-Ruiz, Sánchez-Martínez, F.J. 2015. I+D+i aplicada al control de especies invasoras en ecosistemas fluviales mediterráneos. El caso de la caña común (Arundo donax L.). Ecosistemas 24(1): 32-35. Doi.: 10.7818/ECOS.2015.24-1.06 La problemática relacionada con Arundo donax L. (caña común) ha ido más allá de las implicaciones biológicas asociadas a las especies invasoras. La extensa ocupación de los cañaverales en los márgenes de los ríos en toda la región mediterránea genera un amplio abanico de graves impactos, que ha llevado a que se pusiera en marcha un proyecto de investigación específico para el control de la especie. El proyecto ha consistido en el ensayo de una batería de tratamientos para el control de la especie: herbicidas, tratamientos físicos, mecánicos y biológicos, además del conocimiento de su biología en las zonas donde se han llevado a cabo los tratamientos, mediante el censo de las poblaciones. Por último, se han experimentado técnicas de teledetección para conocer su distribución. Los resultados han mostrado que es posible alcanzar un control severo y duradero de la especie en las zonas donde se ha actuado, tanto por métodos químicos como por métodos biológicos y mecánicos. R+D+i applied to the control of invasive species in Mediterranean river ecosystems. The case of the Giant reed (Arundo donax L.) Jiménez-Ruiz, Sánchez-Martínez, F.J. 2015. R+D+i applied to the control of invasive species in Mediterranean river ecosystems. The case of the Giant reed (Arundo donax L.). Ecosistemas 24(1): 32-35. Doi.: 10.7818/ECOS.2015.24-1.06 he problems related to Arundo donax L. (Giant reed) has gone beyond the biological implications associated with invasive species. The long occupation of the reeds on the banks of rivers in the entire Mediterranean region produces a wide range of serious impacts, which has led to a specific project to control the species got underway. The project has involved testing a battery of treatments for control of the species: herbicides, physical treatments, mechanical and biological, as well as knowledge of the biology of the species in areas where they have carried out the treatments by population census. Finally, we have tested remote sensing techniques to map the distribution of the species. The results have demonstrated the potential to reach a severe and lasting control of the species in areas where it has been performed both by chemical methods such as biological and mechanical methods.