Calag Archive

Regular monitoring by a well-trained pest manager can reduce insecticide use in the nursery without reducing ornamental plant quality. Complete control of pests is not required to sell certain plants. A case in point is a plant sale at the UC Davis Arboretum, where customers ignored or did not recognize some types of pest damage.

The traditional burning of rice straw, after harvesting rice, is being phased out in California's Sacramento Valley under a 1991 state law, and rice growers are faced with seeking other ways of disposal. One option, incorporating rice straw into the soll, will require farmers to carefully evaluate the methods available to them, given their equipment holdings. In general, growers will incur much higher costs to incorporate rice straw, compared with burning it.

We tested the efficacy of tree-shelters on selected container-grown trees in the nursery and on redwood seedlings transplanted into the landscape. Treeshelters accelerated shoot growth of southern magnolia, holly oak and deodar cedar, but root growth was reduced during the first growing season as compared to the controls. Sufficient shoot-root development of the trees was achieved only after two growing seasons. One-year-old redwood seedlings successfully established themselves whether grown in treeshelters or not, while receiving 1/7 to 1/14 as much water as they would in a nursery bed grown in one-gallon containers. The seedlings in treeshelters grew significantly taller.

Blue oaks were planted on a Tuolumne County hardwood rangeland site to assess low-input, low-cost regeneration technology on seedling establishment. After three growing seasons, approximately 22% of the planting spots had a surviving seedling. Costs ranged from $1.88 to $32.58 per surviving tree.

Farm wages in California, as a percentage of farm sales, fell slightly during the 1980s, partly because many farmers switched to hiring workers through Farm Labor Contractors (FLCs). The abuses frequently attributed to FLCs — including underpayment or nonpayment of wages and (over)charges for housing, transportation and work equipment — have renewed legislative interest in regulating their activities.

Through basic research into genetic control of pink bollworm development, we devised a rapid immunological method of determining diapause in pink bollworm larvae — formerly a monthlong process which now requires only 24 hours. This new “ELISA” method has revealed that the pink bollworm larvae in the Imperial Valley sometimes enter diapause weeks ahead of the expected September date for diapause induction. The earliness of diapause induction is correlated with the severity of stress on the cotton plant caused by whitefly infestations.

From its earliest days until now, University of California agricultural scientists have helped to shape and develop California agriculture. As society has changed, university research has continually expanded and diversified. Today's challenges are more complex than ever, but university researchers continue their long tradition of productive service.

Everyday, Californians benefit from 125 years of landmark research performed in the Division of Agriculture and Natural Resources. As the Division celebrates its 125th anniversary, we offer as tribute a list of research feats that enhance daily life.