The Hawkesbury Institute for the Environment's Rainout Shelter (ROS) facility is composed of six large rainout shelters (12m long x 8m wide x 7m tall) that have rain-sensing, automatic retractable roofs. These are situated in the Yarramundi Paddocks of Western Sydney University, off Southee Road, Richmond, NSW. When rain is detected, transparent plastic curtains are automatically deployed and unrolled from the top and on each side of the shelter. After rain ceases, the curtains are automatically raised to their original position. Rainwater is collected from the shelter roofs and can be re-applied to the soil at an appropriate time. These shelters thus allow simulation of changes in rainfall frequency and intensity on large trees. Associated with each shelter is a control plot of equal size. Control and rainout shelter plots are exposed to the same natural environmental conditions except when rain events are excluded from the rainout shelter plots. All plots are extensively equipped with sensors linked to data loggers to continuously monitor environmental conditions.