Calag Archive

There are some indications that the Special Agricultural Worker program has been too successful

Slow water infiltration is a serious problem in some orchards and vineyards on the east side of the San Joaquin Valley. It is often associated with irrigation water low in salt and soils with inherently slow infiltration rates. Gypsum, a calcium salt, is commonly used to improve water infiltration in nonsodic soils. It is the most effective with low-salinity irrigation water (electrical conductivity [EC] < 0.1 decisiemens per meter [dS/m]).

Tomato pinworm occurs principally in tropical tomato-growing areas where winters are mild, particularly Florida, the lower Rio Grande Valley in Texas, southern California, and Mexico. It is not an important pest of fresh market and processing tomatoes in California's major growing region of the central San Joaquin Valley, primarily because of the short production season and cold winters. But it has become a major pest of cherry tomatoes in that area, probably as a result of the long production season and cultural practices unique to this crop. Larvae of tomato pinworm (TPW), Kieferia lycopersicella, cahe most serious damage when they enter t the fruit, although they also mine the foliage. Two cherry

Complete underleaf spray coverage is essential for good control of several pest problems in strawberries. Two-spotted mites (Tetranychus urticae), for example, tend to build up on the undersides of the lowest leaves. Diseases such as common leafspot (Ramularia tulasnii) and powdery mildew (Sphaerotheca humuli) infect the underleaf and can develop into important sources of disease.

Expanding or merging existing gins could improve their efficiency and profits

Only one or two herbicides are available for selective weed control in crucifer crops (broccoli, cabbage, cauliflower, brussels sprouts). With the cancellation of nitrofen, a postemergence herbicide, growers have resorted to hand-weeding of several herbicide-resistant weeds, such as little mallow (Malva parviflora), shepherds-purse (Capsella bursa-pastoris), and hairy nightshade (Solanurn sarrachoides).

Beginning in the early 1970s with the Arab oil embargo and rapidly increasing energy costs, wood came to be viewed as a potential alternative source of renewable energy. Firewood and cogeneration technology, two already-developed uses of wood for energy, received new emphasis. With these new energy-oriented markets for wood, ranchers, forest owners, farmers, and owners of small rural properties began to come to the University of California's Cooperative Extension with questions about planting trees to produce wood energy crops, predominantly firewood. Interest in tree planting escalated when growers heard claims, often unsubstantiated, of extremely high growth rates, especially in eucalyptus.

Eucalyptus was promoted in the early 1900s as the “miracle tree” that would solve wood fiber supply problems in California. Early plantings were intended to be a primary source of lumber, railroad ties, and mining timbers. People began to sour on the purported “miracle tree” when it became evident that eucalyptusgrown in California is subject to excessive shrinkage and warping that prevent it from being used as planned.

In March 1984, we established a test planting of selected eucalyptus and poplar species and clones in the Yuba County foothills. The main objectives were to evaluate survival and growth characteristics over a six-year period and to determine optimum harvest time of intensively managed hardwood trees grown as energy crops under foothill conditions.

To compete with tree and row crops on California's prime agricultural lands, biomass yields may have to exceed 20 dry tons per acre per year at a market price of & 30 per dry ton. The results we report here for a selected clone of Eucalyptus camaldulensis (river red gum), grown in an intensively managed plantation at 2,719 trees per acre, suggest that the required yield can be exceeded by the third year after planting. A clone of E. grandis (rose gum) would probably give similar yields.

This paper outlines the capital outlay needed to get into commercial eucalyptus production and the expected returns under several management regimes. Two possible markets are explored-firewood and biomass-and a break-even land price is calculated for each regime and market at varying price and yield levels.

Most eucalyptus plantations are started with seedlings that are highly variable in growth rate and form. Although breeding programs are under way to improve the quality of eucalyptus seed, the improvements are not expected to come soon.