Column: Has a UC Riverside researcher created the Holy Grail of drought-tolerant lawns?
The University of California-Riverside has been conducting research for the past decade on how plants can survive in conditions of severe drought, and it has its own version of the Holy Grail for creating drought-tolerant lawns.
It’s the Holy Grail of California’s severe drought: a field where a plant’s roots are buried in sand, as in Figure 1, on the left, and where the roots are exposed, as in Figure 1, on the right.
The experiment took place over one season in 2011 at UC Riverside. In early spring, about 300 plants were planted in individual pots in a controlled environment with a temperature of 22 degrees Fahrenheit and only a small amount of water, with only the roots exposed.
The plants were planted in a field planted with a native desert shrub called Yucca brevifolia. In this particular field, water and sunlight were naturally abundant, and the plants grew with no special treatment.
A field that is naturally rich in water and sunlight.
Over the course of the season, the plants grew in the field. They grew to full size, and even to the point of flowering.
But this year, the plants were planted in a similar field but in a different species, Yucca schidigera (Figure 2). This plant, a native desert shrub, tends not to grow as thickly as Yucca brevifolia. Consequently, the plants needed to be harvested, either after about six months of growth.
But the key experiment in 2011 was not the actual planting. Instead, it was the harvesting.
UC Riverside was able to harvest the plants when they grew to full size, and they did so in as short a time as five weeks.
How did the plants survive? It’s because the plants were buried in sand.
A plant buried in sand.
A field where the plants grew for the entire season. They were planted in a field planted with Yucca brevifolia.
Yucca brevifolia, the species native to the field where UC Riverside’s experiment took place.
This is a close-up of a plant, just above the surface in a field of sand.
This is a close-up of a plant, just below the surface in a field of sand