Rome, September 15 - Rome's city council is using a special microchip to monitor the state of large trees that are at risk of toppling as a result of a combination of prolonged drought and extreme weather. The announcement came after three large pine trees uprooted in as many days, crushing cars and injuring two people. The latest incident occurred on Thursday morning near Palazzo Marina on the Lungotevere delle Navi. Prior to that on Tuesday a pine tree toppled in the Prati neighbourhood between viale Mazzini and via di Montegrappa, and another in Via Cassia. The incidents have fuelled safety concerns linked to the state of neglect of public greenery in the capital. Garden maintenance was one of the departments targeted by the criminal organization responsible for the recent Mafia Capitale scandal involving the misappropriation of money destined for city services. Now the procurement process is resuming and "some contracts are being awarded", according to Mayor Virginia Raggi of the anti-establishment Five Star Movement (M5S). "However, it is obviously a huge job... we have mobilised, but there is still much to be done," she said. The city council has begun monitoring 82,000 of the 320,000 large trees present in Rome and pruning them as necessary. Each plant is also monitored using Visual Tree Assistance technology, which gathers data on the condition of the trunk, roots and leaves. In addition, "30 gardeners have been hired in addition to the 170 already in service", according to the city environment department. However, residents are concerned. This is true no more than in Trastevere, where in Via Dandolo two plane trees have toppled in the space of a month and residents are waiting for another that was marked out for felling a year ago to be cut down. The environment department said it would begin intervention in the coming week.