As El Yunque is a tropical rainforest, humidity remains quite high year-round. Therefore, unlike the temperate forests throughout the rest of the country, the Caribbean National Forest does not suffer from fires, and these are usually small and easily controlled. However, there are plenty of trained crew on hand to deal with natural disasters such as landslides, hurricanes and earthquakes. Current weather conditions and emergency warnings are posted on the USDA Forest Service website for the Caribbean National Forest at www.fs.fed.us/r8/caribbean.

El Yunque is an excellent forest to visit because there are relatively few poisonous species and no poisonous snakes. However, there are a few plants that you should watch out for. The juice of the Manchineel, found along Puerto Rico’s coast, can cause severe burns, swelling, and temporary blindness if it comes into contact with the eye. The stinging nettle is another dangerous species; the sharp hairs on the plant contain formic acid and will cause skin irritation. El Yunque is also home to the Carrasco, the Puerto Rican version of poison ivy. There are several other species whose leaves or flowers contain skin irritants. A few have seed pods, leaves or flowers that contain poisonous chemicals such as hydrogen cyanide or calcium oxylate; use common sense when dealing with plants in the forest and never ingest any parts of them.