A major cause of power outages during hurricanes and other storms is trees coming into contact with overhead lines, either directly or as windborne debris.While 100 percent of Belco’s transmission system that carries power from the Central Plant to 34 substations is underground, approximately 45 percent of the distribution system that delivers power to customers across the Island is overhead.Of course, Bermuda has lush vegetation, and Belco addresses it year round in two ways:1: By asking customers to trim trees on their own property, and;2: By managing vegetation along overhead mainline and branch circuits Island-wide.In 2009, Belco introduced a pilot programme that was formalised in 2011, hiring a specialised horticultural and arboricultural firm, Brown and Company Ltd, to keep vegetation 10 feet away from overhead lines, as required.The company prunes trees according to growth rate and habit of individual species to ensure that the required clearance is maintained for three years.What’s more, special attention is given to minimising impact to Bermuda’s endemic plant species, such as the Bermuda Cedar, as well as taking the opportunity to remove invasive species, such as Mexican Pepper and Chinese Fan Palm.Belco’s primary objectives in hiring a specialised horticultural firm to do this work are: to maximise availability of the overhead distribution system and reduce tree-related power interruptions, while also minimising the environmental impact of cutting the trees and creating a sustainable procedure with long-term benefits.To manage the programme, Brown and Company, which uses the safest and most up-to-date practices and techniques, has added three new staff members.