1,721,114 research outputs found
Detecting and identifying Canker Stain of Plane
No full textCeratocystis platani is a lethal Quarantine parasite (Directive 2000/29/EC) reported in Europe since 1972 and likely present since the 40s with serious consequences for public and private gardens in both rural and urban environments.
There are no obvious climatic factors limiting the potential establishment and spread of the pathogen in European Countries where hosts are present, mainly because spread of C. platani is highly human-assisted, but cultural practices and sanitary measures applied in the infected areas may reduce inoculum sources.
This publication was prepared as a technical support for the workshop “Canker Stain of Plane, a Training Weekend in Italy”, organized as a novel extension to Treework Environmental Practice’s ‘Innovations in Arboriculture' seminar series in partnership with De Rebus Plantarum, brand of PAN spinoff of the University of Padova.
The aim of this booklet is not to be a scientific reference, but a kind of “user manual” for consultants and managers, who are day-to-day involved in tree disease surveys and management
A Venturi Effect Can Help Cure Our Trees
No full textIn woody plants, xylem sap moves upwards through the vessels due to a decreasing gradient of water potential from the groundwater to the foliage. According to these factors and their dynamics, small amounts of sap-compatible liquids (i.e. pesticides) can be injected into the xylem system, reaching their target from inside. This endotherapic method, called "trunk injection" or "trunk infusion" (depending on whether the user supplies an external pressure or not), confines the applied chemicals only within the target tree, thereby making it particularly useful in urban situations. The main factors limiting wider use of the traditional drilling methods are related to negative side effects of the holes that must be drilled around the trunk circumference in order to gain access to the xylem vessels beneath the bark. The University of Padova (Italy) recently developed a manual, drill-free instrument with a small, perforated blade that enters the trunk by separating the woody fibers with minimal friction. Furthermore, the lenticular shaped blade reduces the vessels' cross section, increasing sap velocity and allowing the natural uptake of an external liquid up to the leaves, when transpiration rate is substantial. Ports partially close soon after the removal of the blade due to the natural elasticity and turgidity of the plant tissues, and the cambial activity completes the healing process in few weeks
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