Showing papers in "California Agriculture in 1991"
TL;DR: In 1990, a new strain of sweetpotato whitefly invaded Southern California agricultural regions, inflicting heavy damage on cruciferous crops, and problems related to this new strain have impacted vegetable growers throughout California and other growing regions.
Abstract: In 1990, a new strain of sweetpotato whitefly invaded Southern California agricultural regions, inflicting heavy damage on cruciferous crops, Problems related to this new strain have impacted vegetable growers throughout California and other growing regions. In the Imperial Valley, 95% of the 1991 fall melons were disced and total losses to summer and fall crops have been estimated at over $120 million.
73 citations
TL;DR: Control of mealybug infestations in central-coast vineyards was reduced by controlling these honeydew-seeking ants in the spring, using chemical treatments directed at the base of the vines.
Abstract: Recent increases in obscure mealybug infestations in central-coast vineyards have been associated with Argentine ant activity. Mealybug infestations were reduced by controlling these honeydew-seeking ants in the spring, using chemical treatments directed at the base of the vines. This control strategy avoids full coverage treatments disruptive to bene ficials.
58 citations
TL;DR: During a single season, researchers compared California fresh peaches for quality and price at the producer and retail levels and found that prices at both levels declined during the season, but responded differently to changes in quality characteristics.
Abstract: During a single season, researchers compared California fresh peaches for quality and price at the producer and retail levels. While prices at both levels declined during the season, they responded differently to changes in quality characteristics. The results suggest a potential for increased revenues from marketing sweeter, more mature fruit.
46 citations
TL;DR: Field trials showed that for some crops, one timely hand weeding could augment lo wer-rate applications of pre-emergence herbicides to give crop yields equal to or exceeding those obtained with fullseason handWeeding or full-rate herbicide treatments.
Abstract: Applying less herbicide to a vegetable crop can increase weed populations and decrease yields. Field trials showed that for some crops, one timely hand weeding could augment lo wer-rate applications of pre-emergence herbicides to give crop yields equal to or exceeding those obtained with fullseason hand weeding or full-rate herbicide treatments.
34 citations
TL;DR: A European wasp which parasitizes eggs of the destructive southern green stink bug, a pest recently discovered in California, appears to be established and effective against some species of native stink bugs as well.
Abstract: Scientists have introduced a European wasp which parasitizes eggs of the destructive southern green stink bug, a pest recently discovered in California. The beneficial wasp appears to be established and effective against not only the southern green stink bug but some species of native stink bugs as well.
33 citations
TL;DR: The parasitic wasp, Thripobius semiluteus, has been established and spreading for up to four growing seasons at some sites in Southern California avocado orchards and could become an important mortality factor of greenhouse thrips if its widespread establishment is achieved.
Abstract: The parasitic wasp, Thripobius semiluteus, introduced for biological control of greenhouse thrips, has been established and spreading for up to four growing seasons at some sites in Southern California avocado orchards. Studies show that declines in thrips numbers coincide with increasing parasitization by this wasp, which could become an important mortality factor of greenhouse thrips if its widespread establishment is achieved.
25 citations
TL;DR: Cotton was produced using subsurface drip, low-energy precision application (LEPA), scheduled furrow, and conventional furrow irrigation systems in 1989 and subsurface drip irrigation produced the highest net return to the grower through increased cotton yields.
Abstract: Cotton was produced using subsurface drip, low-energy precision application (LEPA), scheduled furrow, and conventional furrow irrigation systems in 1989. Subsurface drip irrigation produced the highest net return to the grower through increased cotton yields. Significant water conservation was achieved with both pressurized irrigation systems (subsurface drip and LEPA). However, computer aided scheduling of furrow irrigation did not result in significant water savings. Pressurized irrigation systems may offer the flexibility and control necessary to significantly limit unnecessary water additions to the shallow groundwater table.
23 citations
TL;DR: European mistletoe (Viscum album) was established in Sonoma County about 90 years ago and has spread a maximum of 7.5 miles and an average of 5 miles from its point of introduction in Sebastopol.
Abstract: European mistletoe (Viscum album) was established in Sonoma County about 90 years ago and has spread a maximum of 75 miles and an average of 5 miles from its point of introduction in Sebastopol The mistletoe now occurs in the nearby communities of Graton, Santa Rosa, Fulton, Cotati, Forestville and Occidental It has been found on 23 different deciduous trees, but is most common on silver maple, apple, black locust, red alder and Fremont cottonwood
20 citations
TL;DR: Research demonstrates that different accessions of AxR#l are equally susceptible to damage by this insect, a form of plant lice, which has spread from two sites in 1983 to more than 70 sites in those two counties.
Abstract: Resistant rootstocks protect grape vines from phylloxera; however, a new form of this insect, Biotype B, threatens the survival of 70% of Napa and Sonoma County vineyards, those which are planted on the rootstock AxR#1. Research demonstrates that different accessions of AxR#l are equally susceptible to damage by this insect, a form of plant lice. The insect has spread from two sites in 1983 to more than 70 sites in those two counties; spread to other grapegrowing counties is likely.
20 citations
TL;DR: The most economical method of reducing potential drainage at this site was to reduce the furrow length by half and decrease the set time by more than one-half during preirrigation, which reduced potential drainage most effectively and increased production, but caused an overall profit loss.
Abstract: Cotton was produced using conventional furrow irrigation, an upgraded continuous-flow furrow design, surge irrigation, and subsurface drlp lrrlgatlon in 1987 and 1988 We found that the most economical method of reducing potential drainage at this site was to reduce the furrow length by half and decrease the set time by more than one-half during preirrigation A subsurface drip system reduced potential drainage most effectively and increased production, but caused an overall profit loss Subsurface drip systems may be profitable if properly designed and managed; however, a substantial yield increase or reduction in drainage disposal costs must be achieved Otherwise, profitability of subsurface drip would be less than that for furrow irrigation systems
19 citations
TL;DR: A recent survey of oak regeneration in four southern Sierra counties found sufficient regeneration of seedlings, but a general shortage of pole-size trees.
Abstract: A recent survey of oak regeneration in four southern Sierra counties found sufficient regeneration of seedlings, but a general shortage of pole-size trees. Managers will need to find ways to encourage oak seedling recruitment into the pole-size class to ensure sustainable oak woodland stands.
Journal Article•
TL;DR: Triticale is a viable alternative feedstuff for poultry because it has a substantially higher protein content than corn and reduces the amount of soybean meal needed in poultry diets.
Abstract: California poultry diets typically contain about 60% corn and 30% soybean meal even though the bulk of these ingredients have to be transported from the Midwest. Triticale is a viable alternative feedstuff for poultry because it has a substantially higher protein content than corn and reduces the amount of soybean meal needed in poultry diets. This potential California crop could save the industry a substantial portion of its current shipments of Midwest corn and soybean meal.
TL;DR: Low-input farming techniques offered energy-saving, cost-effective alternatives for resource-poor farmers of Mexican origin in the Salinas Valley as discussed by the authors, where most of these farmers currently manage small acreages using intensive vegetable cropping systems and high-input technologies.
Abstract: Low-input farming techniques offered energy-saving, cost-effective alternatives for resource-poor farmers of Mexican origin in the Salinas Valley. Most of these farmers currently manage small acreages using intensive vegetable cropping systems and high-input technologies.
TL;DR: Reducing or terminating irrigation on established alfalfa during summer months for two consecutive years reduced crop yields but had no long-term effects on the productive capability of the stand in the third year.
Abstract: Reducing or terminating irrigation on established alfalfa during summer months for two consecutive years reduced crop yields but had no long-term effects on the productive capability of the stand in the third year. Hay quality was negatively affected only when alfalfa was severely water-stressed.
TL;DR: Topical, in-season applications of a whitening agent did not protect the crop from these heat-related injuries of Granny Smith apple fruits.
Abstract: Sunblush, sunburn, and sunscald injury of Granny Smith apple fruits is widespread and results in substantial economic loss when this cultivar is gra wn in the interior valleys of California. Topical, in-season applications of a whitening agent did not protect the crop from these heat-related injuries.
Journal Article•
TL;DR: Agricultural literacy programs now underway in a few California schools are designed to provide students with a fundamental understanding of how our agricultural system works, including its relationship to natural resources and the environment.
Abstract: Agricultural literacy programs now underway in a few California schools are designed to provide students with a fundamental understanding of how our agricultural system works, including its relationship to natural resources and the environment. In statewide surveys, public school administrators and CE county directors agreed such programs should be incorporated into science or social studies classes during late elementary and middle grades. District administrators identified the most important topics to be toxics in the environment, toxics in the food supply, and water quality and policy. Groups surveyed expressed differing opinions, however, about the 1 u P 0 x -
TL;DR: Central Valley grape growers can reduce damage from Pacific mites by inoculating infested vines with the less-damaging Willamette mites, and may become a useful technique for pest management.
Abstract: Central Valley grape growers can reduce damage from Pacific mites by inoculating infested vines with the less-damaging Willamette mites. Such “vaccinations” may become a useful technique for pest management.
TL;DR: Experience with the last major drought in 1976-1977 shows that increased ground water pumping was the critical factor in avoideing economic hardship to farmers and consumers, but such flexibility in water use in the future can only be maintained if ground water is recharged in normal years.
Abstract: Experience with the last major drought in 1976-1977 shows that increased ground water pumping was the critical factor in avoideing economic hardship to farmers and consumers. However, the increse in pumping came with an equally large increase in ground water overdrafts. Such flexibility in water use in the future can only be maintained if ground water is recharged in normal years.
TL;DR: Clorox, Lysol, and Pine-Sol were superior to rubbing alcohol, Listerine, hydrogen peroxide, Agrimycin 17, or Kocide 101 in preventing transmission of fire blight bacteria.
Abstract: Clorox, Lysol, and Pine-Sol were superior to rubbing alcohol, Listerine, hydrogen peroxide, Agrimycin 17, or Kocide 101 in preventing transmission of fire blight bacteria. Spraying or soaking was more effective than dipping to surface-sterilize cutting tools.
TL;DR: Postharvest under- and over-tree sprinkler irrigation led to a reduction in the production of abnormal fruit shapes indicating that canopy climate modification maybe an alternative to growers producing ‘Bing’ cherries in those regions where these abnormal Fruit shapes are prevalent.
Abstract: The ‘Bing’ sweet cherry produces increased numbers of abnormal fruit shapes when grown in certain regions in California, rendering the fruit less marketable. Postharvest under- and over-tree sprinkler irrigation led to a reduction in the production of abnormal fruit shapes indicating that canopy climate modification maybe an alternative to growers producing ‘Bing’ cherries in those regions where these abnormal fruit shapes are prevalent.
TL;DR: Elm leaf beetle control efforts in northern California can be effectively timed using temperature monitoring, and an insecticide applied as a bark band helps preserve the beetle's natural enemies.
Abstract: Elm leaf beetle control efforts in northern California can be effectively timed using temperature monitoring. Two available control methods are a new biological insecticide, and an insecticide applied as a bark band. Both methods help preserve the beetle's natural enemies.
TL;DR: In this paper, a homopolymer of maleic anhydride was injected into buried drip systems to prevent clogging from lime (CaCO3) precipitation in coastal strawberry plots by using this polymer and chlorine for high-bicarbonate waters.
Abstract: Clogging from lime (CaCO3) precipitation can be prevented by injecting a homopolymer of maleic anhydride into buried drip systems. Investigators prevented drip tubing from clogging in coastal strawberry plots by using this polymer and chlorine for high-bicarbonate waters.
TL;DR: In this paper, the authors investigated the effect of irrigation equal to 14% or less of reference evapotranspiration (ETO) on established shrubs and ground covers with no apparent drought-related injury.
Abstract: Results of investigations at UC experiment stations reveal that irrigation equal to 14% or less of reference evapotranspiration (ETO) can be applied to established shrubs and ground covers with no apparent drought-related injury. Adaptation to stress by reduced irrigation during the 2 years preceding full reduction of irrigation eliminated most injury symptoms (such as wilting and leaf necrosis). Application of these findings to established landscapes should significantly reduce water use and the cost of removing excess vegetation.
TL;DR: In this article, the authors explain how pesticides in food are regulated, explore the effectiveness of these regulations, and offer alternatives to consumers who are not satisfied with the current process, while public confidence in the fresh food supply has rebounded in recent months, consumers still identify pesticide residues as a major food safety concern.
Abstract: While public confidence in the fresh food supply has rebounded in recent months, consumers still identify pesticide residues as a major food safety concern - and 8% of Californians say they buy less fresh produce as a result.
This paper explains how pesticides in food are regulated, explores the effectiveness of these regulations, and offers alternatives to consumers who are not satisfied with the current process. It was prepared by four members of a diverse, UC-sponsored committee which met for 20 months to examine the university's food safety research and education.
Appointed by Kenneth Farrell, Vice President of UC's Division of Agriculture and Natural Resources, committee members came from consumer and environmental groups, the California Legislature, farm and food industries, the public health community, the University of California, the California Department of Food and Agriculture, and Stanford University.
Although the diverse membership did not reach consensus on all issues, members clarified their own understandings about food safety. The following article will be used by UC as an educational tool throughout the state.
TL;DR: Competition effects of wild oat were most evident in wheat after the stem elongation stage, and were shown to be equally competitive in southern California studies.
Abstract: Wild oat and wheat were synchronized in their development and were shown to be equally competitive in southern California studies. Competition effects of wild oat were most evident in wheat after the stem elongation stage.
Journal Article•
TL;DR: This study documents the effects of managing on-farm irrigation practices, with and without using CIMIS information, in a Kings County walnut orchard.
Abstract: The California Irrigation Management Information System (CIMIS) originated in 1982. Its purposes were to provide estimates of crop water requirements as influenced by real-time weather conditions and to ensure reasonable use of limited water supplies for farming. This study documents the effects of managing on-farm irrigation practices, with and without using CIMIS information, in a Kings County walnut orchard. In this example, increased water use, increased production, and increased profits were experienced as a result of implementing CIMIS information.
TL;DR: Southern California restaurants are increasing their use of fresh culinary herbs, and opportunities exist for well-placed growers to take advantage of the restauranteurs' desire to deal directly with farmers.
Abstract: Southern California restaurants are increasing their use of fresh culinary herbs. Opportunities exist for well-placed growers to take advantage of the restauranteurs' desire to deal directly with farmers.
TL;DR: Researchers have found a fungicide that provides excellent control of cavity spot, the most damaging carrot disease in California, though it is not yet registered for use on carrots.
Abstract: No control measures are now available for reducing losses to cavity spot, the most damaging carrot disease in California Researchers have found a fungicide that provides excellent control of the disease, though it is not yet registered for use on carrots
TL;DR: California's environmental horticulture industry has economic activity in excess of $7.2 billion annually, but its numerous segments are not unified, and university research and extension activities could significantly assist in defining industry problems and extending practical solutions based on applied and basic research.
Abstract: California's environmental horticulture industry has economic activity in excess of $72 billion annually, but its numerous segments are not unified University research and extension activities could significantly assist in defining industry problems and extending practical solutions based on applied and basic research
TL;DR: In this article, an evaporation pan scheduling algorithm was used to predict the irrigation requirements of greenhouse roses, which can be used by growers to minimize overirrigation while guarding against water stress that reduces yields.
Abstract: Evaporation pan scheduling can accurately predict the irrigation requirements of greenhouse roses. This simple system can be used by growers to minimize overirrigation while guarding against water stress that reduces yields.