Precision forestry and traceability services for the certification of timber products require reliable systems for the identification of items throughout the supply chains, starting from the inventory of standing trees. AutoID systems based on radio frequency identification (RFID) are regarded as the most promising technology for this purpose. Nevertheless, there is no information available regarding the capacity of RFID tags to withstand the climatic and biological wearing agents present in forests for long periods, while maintaining the stored information and the capacity to return a readable signal over time. In order to assess this aspect, seven RFID UHF tags, selected from the range of commercial models or developed for this purpose, were used to mark standing trees for two years. Results showed that all models proved able to maintain sufficient operative capacity to be identified with manual (proximity) readers. Some models suffered damage to the protective case or were deformed, with a strong decrease in readability. Tags with simple structure and lower cost proved strong enough to endure one year without major drawbacks, and could be best suited for deployment in integrated auto-ID supply chains if used as disposable components. More complex and expensive tags are best suited for long-term marking, but application on living trees requires specific solutions to prevent damage due to stem growth.