So-called 'native' plants offer no guarantee of water conservation

Golf Course News, Nov 2001

TEMPE, Ariz. - Superintendents take note: using plants identified as 'native' may alter your water conservation objectives.

Reported studies from the American Water Works Association Research Foundation and plant biologists at Arizona State University here both found that so-called xeriscape or native landscapes were actually receiving more water than traditional style landscapes.

ASU scientist Chris Martin, Ph.D., found that desert plants such as acacia, brittle bush, creosote bush and mesquite could use two to three times as much water as flooded alfalfa or turfgrass.

According to the findings, the problem is not necessarily with the plant, whether it's a desert plant or lawn, but with watering management practices. Desert plants survive because they are capable of absorbing large amounts of water very quickly in order to survive in an area with infrequent rainfall.

When landscape water is made available, most plants act as "water pumps" and absorb the resource rapidly while growing at tremendous rates.

The studies recommend that landscape managers learn the growth cycles and true water requirements of managed plants to conserve water effectively.

According to researchers, even properly established turfgrass can survive on very limited water if it is allowed to go dormant during hotter, dryer times of the year, as long as the plant's crown is kept hydrated with as little as one-quarter inch of water a week.