Our Findings (Summary)

Below is a summary of the observations for the overall project one year after planting. Also see detailed findings ("Our Findings") with photos and charts for each of the three category links on the left (Irrigation Trial, Native Grass Turf and Native Grass Meadow).

October 2011 – Conclusions

'UC Verde' Buffalograss is one of the most promising species in reducing water use. It looked green even when very little water was applied, and clipping weights were only slightly reduced at the lowest applied irrigation level. In December we plan to spray a portion of each UC Verde plot with biodegradable green dye, and we will plant a portion of each to annual ryegrass to show how the winter dormancy drawback can be overcome.

Sedge species are also promising, especially dune sedge (Carex pansa), which produces less growth and less rust than field sedge (Carex praegracilis), and the mowed turf is less stiff than field sedge.

Several native grasses look promising, but all have at least some dormant or semi-dormant period. Summer and winter dormancy is less of an issue in coastal areas. In the first year, these species showed drought stress under moderate deficit irrigation, but root depth may increase in subsequent years, resulting in greater drought tolerance.

One native grass, Hall’s bentgrass (Agrostis hallii), which was planted by plugs, did not perform satisfactorily. We removed it this fall and seeded purple needlegrass (Nassella pulchra) in its place.

September 23, 2011 – Irrigation treatments end. All plots were brought back to full irrigation in order to allow plants to fully develop and fill in to prepare for reinstatement of treatments in spring 2012.

August 24, 2011 – Both tall fescue and sedges (especially Carex praegracilis) showed severe drought stress under the lowest irrigation level.

July 28, 2011 – Irrigation treatments began. Prior to commencing the trial, a water audit was performed to measure the output of our sprinklers. Irrigation levels include full, three-fourths, and half rate, based on reference evapotranspiration (ETo). Visit the Irrigation Trial link at the left for more details on irrigation levels.

July 25, 2011 – Small dead patches in tall fescue, two small patches in the tufted hairgrass (Deschampsia caespitosa), one small patch in the seashore bentgrass (Agrostis pallens). After a soil drench that turned up no measurable insect population, and a lab analysis that was negative for disease, we ended up diagnosing it as possible damage from dog urine.