If a tree falls in the forest, will it make a sound? Of course, it will, and a U.S. start-up has found a way to make sure it doesn't go unheard.

Illegal logging has been a pressing issue for years but not much has been done about it because catching culprits is tricky. By the time authorities get to an area of concern, illegal loggers have already packed up and left, leaving a wake of destruction in their paths. California-based Rainforest Connection aims to put a stop to this by equipping forests with smartphones.

The system is simple. Old smartphones are wrapped in waterproof cases and hung up high on trees so they are not easy to get to. Each device will also be attached to a solar cell so it has continuous power. Once turned on, the smartphones will then record all sounds it captures in the forest at intervals. These recordings are then transmitted through a local cellular network, stored in a central server and analyzed by software.

If the software picks up the sound of chainsaws, it alerts the authorities, triangulating the position of illegal loggers using recordings from different smartphones in the forest. How many smartphones does it take to protect a forest? Just one device can cover 300 hectares.

The system was first implemented at the Kalaweit Supayang Nature Conservation Reserve in Indonesia, and within two weeks of installing the smartphones, the 135-hectare reserve experienced a drop in illegal logging activity. A year later, illegal loggers had completely ceased their activities within the reserve.

While the system has been designed to detect the sounds of chainsaws, it can also be configured to send out alerts when gunshots are recorded, signifying the presence of poachers in the area and protecting the animals of the forest as well.

What makes the system effective is that it sends out real-time alerts. Response time may vary but first responders have a better shot at catching illegal loggers and poachers in the act when given exact locations.

No convictions yet have been made with the help of Rainforest Connection but the drop in illegal logging activities in Indonesia is proof enough that using smartphones to bug the forest is effective.

Web and mobile apps are scheduled to be released towards the end of 2014 to allow the Rainforest Connection's Kickstarter backers to listen to the sounds of an African rainforest as it is being protected by the company's system. The company's current mobile app only streams sounds recorded from a forest in Sumatra, Indonesia.