Evaluation of Climate-Based Controllers for Landscape Irrigation.

Water conservation is an important issue nowadays. Daily 96.9 million m³ of water is consumed in the United States, which approximately 24.7 million m³ (25.5 %) is used for watering lawns, plants, and gardens (Vickers, 2001). In Utah, water is a limited resource; it’s the second most arid state and is prone to droughts. In addition, is one of the fastest and most highly urbanized states, therefore residential and commercial landscape watering is estimated to be the largest of potential source to strengthen the objective of urban water conservation. Climate Based Controllers, also known as “Smart Controllers” have been developed as one of different technologies to succeed in the task of water conservation. This controller measures depletion of available plant soil moisture in order to operate an irrigation system. The main purpose of this study is to evaluate the applicability of “Smart Controllers” in field and determine whether different climate-based irrigation controller technologies achieve different levels of landscape water conservation without negatively impacting landscape quality. The experiment took place at USU Green Ville Farm, in an area of 930m², divided in 20 small plots of 28m² each. The plots were composed of an area of turfgrass (21m²) and another of ornamental plants (7m²). Four treatmenst were evaluated, with 5 replications each, set-up in a randomized complete block design. Each treatment represented a different controller, two sites used on-site sensors, one used paging signal technology, and there was a blank or control programmed using the recommendations given by the extension program for landscape irrigation. Measurements of water applied, and soil moisture were collected; as well as plant growth and quality using quality ratings, stomatal conductance, canopy temperature, height and width. Currently, the experiment is being installed and data will be collected in the coming summer months. It has been estimated that “smart controllers” could save up to 30% of water applied on landscapes.