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Preplant soil fumigation with methyl bromide is scheduled to be phased out by 2005. Chemical and nonchemical alternatives are being researched and identified. Soil solarization and/or biofumigation can help fill the gap in certain cases. These alternative methods of soil disinfestation are also of value to organic growers, home gardeners and others who will not or cannot use the soil fumigation chemicals employed by many conventional commercial growers.

Common bermudagrass is an invasive perennial weed of cool-season turfgrass in California. Complete renovation and loss of use of the turf for up to 4 months has been the only practical method of restoring desirable cool-season turfgrasses. In studies in Southern and Northern California, common bermudagrass was suppressed with sequential herbicide applications, allowing seedling establishment and regrowth of competitive cool-season turfgrass species. This was accomplished without losing use of the turf area.

Mulches have been used for many years to control weeds by smothering the weed seedlings. A 2-year study in a Lodi grape vineyard compared the weed-control effectiveness of herbicides, cultivation, cover crop biomass and wood-chip mulch and the cost of these practices. The most effective and least expensive treatment over the 2 years was the use of preemergence herbicides and a post-emergence herbicide as needed. Growing cover crops, chopping the biomass and placing it into the vine row was very effective the second year, when more biomass was produced and weeds were controlled prior to mulch placement. The mulch was persistent in the field and should give long-term weed-control benefits, which were not evaluated in this study.

Kikuyu grass is an invasive perennial weed of turf grass in California. Currently, complete renovation of infested turf is the most practical means of control, but this process can cost more than $1,500 per acre and it removes the sward from use for up to 3 months. A less disruptive method uses multiple selective herbicide treatments with MSMA, triclopyr or a combination of MSMA plus triclopyr. This method inhibits the competitive ability of kikuyugrass while allowing the growth of desirable cool-season turf species.

Soil solarization in summers in Central Valley and near-coastal sites controlled bermudagrass and johnsongrass covered by polyethylene tarps. Field bindweed was also controlled during solarization, but regrowth occurred. To maximize control and reduce the “edge” effect – the regrowth of weeds at the edges of fields when they are not covered by tarps – the soil must be completely covered with intact polyethylene.

A weed management system tested for small farms combines plastic mulch, drip irrigation, and in some cases, a preplant broad-spectrum weed killer.

Orchard cover crops are generally thought to be beneficial in the management of pests, especially certain insects and mites. Depending on how they are manipulated, however, cover crops have the potential to increase damage from some pests. If cover crops are not managed correctly-for example, are mowed at the wrong time or are under stress for moisture-plant-feeding insects may move from the orchard floor into the trees to feed on developing fruit.

Selection of an orchard floor management system is based on several considerations, often including its potential effect on water use, water infiltration, and soil compaction. Information on these factors has been limited, however, because many previous studies have compared only a few treatments or have produced site-specific recommendations that did not consider differences in soil characteristics or orchard management.

Vegetation on orchard floors varies considerably among orchards and growing regions. Weed populations also vary within orchards. The complex of species includes many winter and summer annual plants and often some perennials. Numbers range in any given orchard from a few species (10 to 12) to more than 20.

In selecting an orchard floor management system it is necessary to evaluate the costs of developing and maintaining the systems under consideration. We estimated sample costs for the five systems studied as treatments of the centers between the tree rows - Blando bromegrass, Salina strawberry clover, resident vegetation, residual herbicide, and chemical mow, as described in the introductory article.

Orchard floor management systems used in California almonds vary from planting cover crops between the tree rows to management of the existing ground cover or weeds in the orchard to removal of the vegetation on the soil surface. Cover crops, sometimes called living mulches, have been used in orchards for many years. Many orchardists have successfully converted their weed management practices from repeated disking to maintenance of the vegetation through mowing.

Vineyard weeds vary from location to location but often include a broad complex of 15 to 25 species. Most vineyard managers control weeds by applying herbicides or by plowing a strip down the crop row. Weeds between the rows are controlled by discing or mowing (mechanical or chemical) in a total weed control program. In some vineyards, annual or perennial grass or broadleaf cover crops are planted between the rows.

Annual weed competition in young orchards and vineyards can often reduce first-year growth as much as 50 percent. In fields with extremely heavy weed populations and limited irrigation, trees and vines have been killed by weeds in the first year. Perennial weeds are even more harmful than annual weeds to newly planted trees and vines. Even though a persistent tillage program can give a practical control of perennial grasses, many growers still have serious problems with perennial weeds.

Anyone who has spent a summer in the San Joaquin Valley hoeing johnson grass, bermudagrass, or nutsedge (nutgrass) out of a young orchard or has labored on a hot summer afternoon trying to pull perennial bindweed out of a young vineyard or a cotton field will be much interested in Roundup (glyphosate). This new herbicide showed promise in earlier studies (California Agriculture, February 1973) and has since proved to be an outstanding product against most annual and perennial weeds.

Yellow oxalis (Oxalis corniculata) is frequently a serious pest in greenhouse rose production. When steam fumigation precedes planting, the oxalis seedlings and plants are killed. However, due to the three to five year interval between steam treatments, when the roses are producing, reinfestation occurs by seed from adjacent beds. The seed is ejected from the seed pod with sufficient force to carry for several feet into previously clean beds. The seeds cling to clothing and often to animals, enabling them to be spread throughout the greenhouse and even to be introduced from the outside.

Weeds are a problem in transplanted carnations during early stages of development when there can be no soil fumigation or steam sterilization. Early mechanical control of weeds is made impossible by the wire, plastic or bamboo netting that is placed on beds at planting for plant support. The only alternative is expensive hand weeding. The study reported here evaluates herbicides for control of weeds in transplanted carnations in ground beds.

Linuron applications at 1 lb per acre severely injured only one of the nine ground cover species tested in this study (C. edule). Amino triazole at 1 lb per acre was applied to all species, except Ajuga repens or Delasperma alba, without severe injury. Injury from MCPP was less severe than 2,4-D in most instances and would appear to be safer in these tests at herbicidal rates. However, injury was apparent from MCPP on Ajuga repens, although 2,4-D amine did not appear to cause injury in this test. Bromoxynil appeared to have contact effects only (as indicated by early leaf burning) on Carpobrotus edule, Delasperma alba, Hypericum calycinum, and Vinca minor; however, regrowth was normal.

Field bindweed (Convolvulus arvensis) is a widespread problem in coastal vineyards of central and northern California. Field trials by the Agricultural Extension Service since 1963 have compared several formulations, rates, and timing of 2,4-dichlorophenoxyacetic acid (2,4-D) sprays. Wax bars impregnated with 2,4-D have also been tried. None of the treatments in these trials have given commercial season-long control (table 1).

THE NEAT ROWS OF WHITE AND PINK blooming trees in the San Joaquin and Sacramento valleys will have a new look this spring. Strips of brown soil bordered by green interspaces may be seen down many of the tree rows. These weed-free strips will probably be the result of herbicides applied before the rainy season and prior to weed emergence.

SIMAZINE (PRINCEP), a persistent pre-emergence herbicide, has given broad-spectrum weed control in orchard crops. Generally it has been used by orchardists with excellent results. As it depends on water to activate it and move it into the soil, simazine's effectiveness is dependent on soil environment and the cultural practices employed.

Weed costs for the state's 110,000 acres of almond orchards totaled $1,160,000 in 1964, according to estimates by the California State Chamber of Commerce Weed Control Committee. In the same year, a survey by the Agricultural Extension Service indicated that 88% of almond orchard weeds were annuals and 12% perennials. Most of the cost of control has been for machinery and hand labor necessary to control the weeds in the tree row. Continued disking has also frequently been injurious to both roots and trunks of young trees.

Johnsongrass, Sorghum halepense, is the most serious perennial weed control problem in California orchards. This fast-growing, warm-season weed propagates prolifically from seed and underground rhizomes. The fleshy underground stems provide the necessary overwintering mechanism by which this plant gets an early start in competing with crop plants, as well as other weeds. In established trees and in young, producing orchards, competition from Johnsongrass may reduce nutrients, moisture, and light. In a field test at the Kearney Field Station, Fresno County, Johnsongrass seedlings were controlled in the nursery row with various soil-persistent herbicides. MSMA is not currently registered (or recommended by University of California) for orchard use. Dalapon is not registered for use on walnuts or almonds.

Pre-emergence herbicides such as simazine and diuron (Karmex) are widely used for annual weed control in commercial apple and pear producing areas outside California. A 1964-65 survey of California orchards showed that very few acres of apples and only about 1000 acres of pears were sprayed for annual-weed control during that winter. Both simazine and diuron have been registered for use in apples and pears by the state of California and USDA. New developments in orchard culture, including hedge-row planting of pears, together with the scarcity of hand labor, have resulted in a recent upsurge of interest on the part of California orchardists.

Imaging techniques in anatomy have developed rapidly over the last decades through the emergence of various 3D scanning systems. Depending on the dissection level, non-contact or tactile contact methods can be applied on the targeted structure. The aim of this study was to assess the inter and intra-observer reproducibility of an ArUco-based localisation stylus, that is, a manual technique on a hand-held stylus. Ten fresh-frozen, unembalmed adult arms were used to digitalise the glenoid cartilage related to the glenohumeral joint and the contour of the clavicle cartilage related to the acromioclavicular joint. Three operators performed consecutive digitalisations of each cartilage contour using an ArUco-based localisation stylus recorded by a single monocular camera. The shape of each cartilage was defined by nine shape parameters. Intra-observer repeatability and inter-observer reproducibility were computed using an intra-class correlation (ICC) for each of these parameters. Overall, 35.2 ± 2.4 s and 26.6 ± 10.2 s were required by each examiner to digitalise the contour of a glenoid and acromioclavicular cartilage, respectively. For most parameters, good-to-excellent agreements were observed concerning intra-observer (ICC ranging between 0.81 and 1.00) and inter-observer (ICC ranging between 0.75 and 0.99) reproducibility. To conclude, through a fast and versatile process, the use of an ArUco-based localisation stylus can be a reliable low-cost alternative to conventional imaging methods to digitalise shoulder cartilage contours., (© 2024 The Authors. Journal of Anatomy published by John Wiley & Sons Ltd on behalf of Anatomical Society.)