Happenings at Hopland REC
Subterranean clover (Trifolium subterraneum), the name often shortened to "sub-clover", is a species native to northwestern Europe. It is now widespread in many parts of the world, and is one of the most commonly grown forage crops in Australia. Sub-clover is extremely high in protein value, highly palatable to livestock, fixes nitrogen into the soil, and withstands heavy grazing (which actually promotes the sub-clover stand). The University of California and Australian researchers worked for decades together to find correct varietal types and rhizobium (soil bacteria capable of forming symbiotic nodules on the roots of legumes and then fix atmospheric nitrogen into the soil) that is needed to fit the various micro-climates. Nowadays when one purchases sub-clover seed from the local farm supply store one actually gets a bag of pre-coated seed that has the rhizobium pel-coated onto the surface of each seed. Much of the mentioned field research was done at HREC by UC Davis agronomists.
Oh, the plant is given its name because it normally blooms close to the ground, and as the seed-burr forms the plant actually buries the seed into and sometimes below the surface of the soil, thus the name "subterranean".
Barn Owls (Tyto alba) have used oak woodlands and valley floors of California for thousands of years. These birds naturally rely on large cavities, either in trees, snags, or cliff faces for daytime roosts and nesting sites. As California became "civilized" many of these natural cavities disappeared (for example: the loss of many large California Valley Oaks due the clearing of land for agriculture and urban development) so many owls turn to old barns and silos for roost sites (thus their name). However, these usually have very limited nest site availability, so, the placement of artificial nest boxes provides nest cavities for many of these birds. HREC has several of such nest boxes placed in strategic locations, and here you see a barn owl who's mate is currently sitting on eggs or has young in a nest box inside one of HREC's old barns.
Since the 1960's HREC has maintained a unique research facility - a set of lysimeters. Each lysimeter consists of a steel tank, which is filled with soil, plumbed to collect all water draining out of that soil, and buried into a hill slope so that the soil within the tanks is similar in conditions to blocks of soil found in the natural system. This unique setup allows researchers to test how different treatments impact the loss of water, nutrients, pesticdes, etc., from ecosystems. This photo shows HREC's current 72-tank lysimeter facility, recently built by HREC staff with funds from the "National Research Initiative Cooperative State Research, Education and Extension Service".
The Western Harvest Mouse (Reithrodontomys megalotis) is locally common throughout the western two-thirds of the of the United States (lower 48 states except for the high Rocky Mtns). This secretive rodent prefers open mesa habitats with thick grass and forb vegetation and a build-up of dense litter. At HREC they can be found in the long-ungrazed portions of the Center. Bristly fur, a long bi-colored tail, and whitish feet are all characteristics of this native species.
HREC is blessed with location as the Center is located at a "hub" of climate zones and maritime influence and soil and elevation differences. As a result, HREC has over a dozen species of oaks that can be found on on the Center. Here you see a Coast Live Oak (Quercus agrifolia) with fresh new leaves forming and catkins ready to bloom. Coast Live Oaks are only found at scattered locations at the lower elevations on the west side of the Center.