ag davis rotary table made in china

The ULTRARON is a precision-engineered rotary table, produced entirely at A.G. Davis - AA Gage, with applications for inspection, tool room and/or production machining. The ULTRARON"s accuracy is made possible by the use of precision lapped balls and integral ground races. The ULTRARON has a standard concentricity accuracy of 30 millionths T.I.R. (0.000030) and a wobble or rotating parallelism is held within 100 millionths (0.0001) on sizes to 24" in diameter.

The A.G. Davis - AA Gage Precision Broach Rotary Tables are high precision rotary systems manufactured for precision broaching applications. The Broach Rotary Tables can be supplied with stand-alone or rack-mounted controller, or can be interfaced to your operational Rotary Axis Control.

The Precision Rotary Tables are designed for use in Metrology, Inspection, and other precision applications. The Rotary Tables can be supplied with stand-alone or rack-mounted controllers, or can be interfaced to your operational Rotary Axis Control. The control is a solid-state, closed-loop system incorporating the latest State-of-the-Art concepts and can include IEEE or RS232 interface for remote program control.

The Air Float Rotary Table consists of hardened steel faceplate, which is floated on air in the thrust plane and centered by preload ball bearings radially during rotation. After an index move is completed the Air float is shut off allowing the faceplate to rest on the base of the rotary table producing excellent wobble characteristics. This action also friction locks the Air Float Rotary Table. A high-grade meehanite base casting is used to support the faceplate. Standard faceplate mounting pattern is by threaded hole patterns with other configurations available. The Air Float Type Precision Rotary Table can only be used with the faceplate in the horizontal plane.

The Ball Bearing Rotary Table consists of hardened steel faceplate supported by a maximum diameter preloaded angular contact ball bearing. The large diameter ball bearing produces excellent wobble characteristics. The preloaded ball bearing along with the closed loop servo system provides for continuous as well as point-to-point measuring. A high-grade meehanite base casting is used to support the ball bearing. Standard faceplate mounting pattern is by threaded hole patterns with other configurations available.

The Air Bearing Rotary Table consists of hardened and stabilized stainless steels and/or high-grade steels with corrosion resistant coatings. The base is made from high-grade meehanite castings. The Rotary Table employs a fully trapped gas bearing for both radial and thrust planes. The gas bearing jets are manufactured of precision machined gemstones. The air bearing along with the closed loop servo system provides for continuous as well as point to point measuring. Standard faceplate piece part hold down consists of threaded hole patterns, or special configurations are optionally available.

Air bearings require small clearances between rotating members. The possibility of these surfaces contacting each other during rotation is a major concern of air bearing users. Typically when this touch down does occur conventional air bearings will seize up and require major repairs. A.G. Davis-AA Gage has eliminated this possibility. The air orifice manifold detail is constructed from hardened stainless steel. The opposing surfaces are constructed from high-grade hardened steel and coated with a proprietary material. This construction permits the air bearing to lose air pressure while rotating even under maximum rated load and not damage the air bearing thrust and radial precision surfaces. After the air pressure is reinstated the bearing will freely operate as before.

The servo drive utilizes a capstan type friction wheel drive system. This drive system eliminates backlash (lost motion) between the servo motor and the Rotary Table it must position. The zero backlash condition provides an excellent foundation for a servo system which positions accurately without instability over a wide range of payload conditions.

The drive is constructed to eliminate any side loading of the rotary table bearings. Tangential loading only. This is accomplished by mounting the entire capstan drive package on a pivot which is tangent to the table drive rim. The main capstan drives on the O.D. of the drive rim while an opposing wheel bearing runs on the I.D. of the drive rim. The drive force required to engage the main capstan is provided by the opposing wheel bearing which creates a pinching action on the drive rim. This pinching action along with the pivot allow the drive to follow the drive rim"s motion without imparting any force to the rotary tables precision bearings. Note -unwanted side loading of the rotary table bearing will cause an increase

The base of the rotary table can be provided with air jet pads. These pads when actuated allow the rotary table to float on a level continuous flat surface. This feature is particularly convenient to CMM users who often move the rotary table to other locations on the CMM for various applications. The Air Ride is actuated by a dead man switch (automatically turns off when released). The switch is located adjacent to the drive cover.

A micro switch can be provided to close approximately 10° to 15° before the encoder"s marker pulse. The approach direction can be either clockwise or counterclockwise. Specify the desired approach direction when ordering. The encoder marker pulse will be located within 5° of the rotary tables zero position (the RT outline drawing shows the rotary table at it"s zero position).

A switch (DISENGAGE/ENGAGE DRIVE) can be provided adjacent to the drive cover. This toggle switch actuates a cylinder that alternately disengages and/or engages the drive. This switch also turns the Air Float Bearing on and off. This permits freewheel rotation of the face plate for faster centering and complete manual operation.

The ULTRARON is of compact design and rugged construction. The table is actually a large bearing assembly constructed with two rows of precision lapped balls, preloaded against each other, near the outer diameter. The base of the table is the outer race and the inner race is attached to the tabletop. Locating the precision lapped balls near the outer diameter assures maximum table stability and enables the ULTRARON to withstand heavy axial and radial loading. It also allows large through holes where the application requires it. The ULTRARON is stiff enough to be used for machining operations.

The manual ULTRARON operates freely whether in horizontal or vertical position. It is available in 6" to 48" base diameters with special top plates to 84" in diameter. Digital readouts can be adapted to all ULTRARON tables.

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A. G. Davis - AA Gage has been the industry leader in providing the design and manufacture for precision gages of all types, from small attribute (go/no go) gages, variable (data) gages, standard gages and components, to transfer line, gantry loaded semi-automatic and fully automatic inspection machines.

It began with being photojournalists for numerous magazines worldwide, focusing on endurance racing such as Le Mans and Baja races. Just a few years in, Gayle’s computer skills came into play as she helped photographers and magazines alike make the transition from film to digital photography and publishing.

Peter then designed and built an aerodynamic car trailer to transport his sports car. Soon others were asking if one of these groundbreaking trailers could be built for them. Gayle saw an opportunity and founded Aerovault trailers, setting up a factory in Henderson, NV with custom-built equipment and defining the production process using LEAN techniques. Today Gayle manages both BRE and Aerovault and travels extensively with Peter for appearances and speaking engagements, fitting in an Aerovault trailer display whenever possible!

David Cheresh is a distinguished professor and vice chair of research in the Department of Pathology in the School of Medicine at the University of California, San Diego (UCSD). He is also Director for Translational Research at the Moores UCSD Cancer Center. Previously, David was a professor in the Departments of Immunology and Vascular Biology at The Scripps Research Institute. Dr. Cheresh earned his Ph.D. in Immunology from the University of Miami, FL, and trained as a postdoctoral scientist at the Scripps Research Institute where he remained on the faculty before joining UCSD in 2005. He is the recipient of various awards including the 15th Hans Linder Memorial Lecture from the Weizmann Institute of Science in Rehovot, Israel, the XXIII Annual Myron Karon Memorial Lectureship from the University of Southern California, the Robert Flynn Professorship Award from Tufts University School of Medicine, the Judah Folkman lectureship, the Paget-Ewing award from the Metastasis Research Society/AACR and was a recipient of The American Cancer Society Faculty Research Award and a Merit Award from the National Cancer Institute. Cheresh also is a recipient of an NIH MERIT award - an Outstanding Investigator Award from the National Cancer Institute.  Cheresh has trained over 100 postdoctoral and graduate students many of which have continued their careers and academia.  He has published 260 papers, many in top-level journals and fourteen of these have been cited in excess of 1000 times.

These studies have led to the development of integrin antagonists as novel therapeutics for cancer treatment that function to suppress the growth of angiogenic blood vessels.  Two drugs that have developed from his work include Vitaxin (Abegrin), a humanized monoclonal antibody that targets αvβ3, and Cilengitide, a cyclic peptide antagonist of integrins αvβ3 and αvβ5.  Both of these drugs showed clinical activity in cancer patients in Phase II trials. Cheresh was the scientific founder of TargeGen Inc., which developed a selective JAK2 inhibitor recently approved by the FDA in August of 2019 for patients with myelofibrosis.

Gregg and his wife Jody live on their ranch in Moorpark, California. They have a son, Justin who is a computer engineer in the Washington, DC area. Gregg and Jody drive Welsh Ponies and collect antique horse-drawn carriages. Gregg enjoys flying airplanes.

Ron is a 1981 graduate of Cal Poly San Luis Obispo and holds a Bachelor of Science degree in Agriculture Business. He currently serves on several agricultural, nonprofit, and business boards, and currently co-chairs the Dean"s Leadership Council.

Dave Jessup is an accomplished Wildlife Veterinarian and researcher. He received his bachelor’s in zoology from the University of Washington, DVM from Washington State University, and his Master of Preventive Veterinary Medicine at UC Davis, where he also received his board certification in zoological medicine. He is a recipient of the 2010 Emil Dolensk Award given by the American Association of Zoo Veterinarians. He was granted this award because of his exceptional contributions to the conservation, care, and understanding of zoo and free-ranging wildlife. He was the first veterinarian hired by the California Department of Fish and Wildlife, where he served a productive career in various capacities for more than 33 years, the last 15 in Santa Cruz, California, as Senior Wildlife Veterinarian and Supervisor of the Marine Wildlife Veterinary Care and Research Center. Consequently, Jessup served as Executive Manager of the Wildlife Disease Association (WDA), an international non-profit scientific organization. He has mentored many who followed in his footsteps, including UC Davis students and alumni, and created an endowment to establish the Free-Ranging Wildlife Health Residency at the Karen C. Drayer Wildlife Health Center.

John Klacking is the Chief Business Officer of Gallant Therapeutics. He holds a Bachelor of Science degree from the University of California - Davis, and a Ph.D. in Biochemistry from the University of Nevada, where he was an Allie M. Lee Fellow.

A former Senior Vice President of Salomon Smith Barney, John founded Angiocrine Bioscience, a stem cell therapeutic company, with Dr. Shahin Rafii at Cornell Weill Medical Center in New York City. Prior to Angiocrine he founded Angelica Therapeutics, a San Francisco Bay Area cancer-focused biotech company. He is the author of over 350 business, financial and scientific articles, and serves on the Northern Nevada Public Health Board. John was named one of Nevada"s ten top financial consultants by Nevada Business Magazine.

Tragically, John lost his wife and son to cancer. Through his loss he has dedicated himself to raising millions of dollars to help academia and non-profit institutions. In addition to serving on the Dean’s Leadership Council, he played the key role in the founding of the school’s SeaDoc Society, which is dedicated to protecting the health of marine life of the Salish Sea.

Dr. Klingborg earned undergraduate degrees in rhetoric and zoology (1987) and his doctorate in veterinary medicine (1992) from the University of California at Davis. For more than a decade, he also served as guest faculty at his alma mater and shared with veterinary students how communication makes practice more rewarding for both the client and the veterinarian.

Julia Lewis received her bachelor’s from Cornell University and her DVM and Master’s in Public Health from UC Davis. She also completed her residency in lab animal medicine at UC Davis and a Don Low/CVMA Practitioner Fellowship in Anesthesia

Her prior roles have included positions at ALZA Pharmaceuticals, a subsidiary of Johnson & Johnson, and Priority Veterinary Management Consultants, where she provided consulting services to veterinarians around the country.

Dr. McConnell was a practicing veterinarian at Wilmington Animal Hospital in Delaware. She holds a BS from Cornell University, an MBA from Purdue University and a DVM degree from University of California, Davis.

Charles’ business acumen has also included venture capital, management consulting and real estate. In addition to his business interests, Charles is very involved in supporting philanthropic causes through the Max & Gertrude Newman- Charles & Phyllis Newman Foundation, and as a foundation Director of Adath Jeshurun Foundation. Oncology is another key focus supported through Prometheus Life where he serves as President. Prometheus Life’s priorities are to further treatments, collaboration, and education in treatments for oncology and related diseases.

Dr. Pillsbury has established scholarships in her mother"s name, such as the Frances Park Pillsbury Memorial Scholarship for the School of Veterinary Medicine, Davis.

Valerie Reynoso Piotrowski is the director of key advertising accounts for Comstock’s magazine, where she directs print advertising, develops special sections, courts new corporate and business clients, and writes for the magazine. She also serves as a ghostwriter for high net worth clients and consults with senior managers on developing successful plans for promotions, salary increases, and new benefits.  Prior to commencing her second decade at Comstock’s, Valerie served in the nonprofit industry for 12 years and most recently as a senior consultant for business development for the Greater Sacramento Economic Council.  She was Executive Director of The Dominguez Dream, a nonprofit dedicated to empowering children in underserved communities with literacy and STEAM (Science, Technology, Engineering, Arts, and Math) funding.  During her tenure, the nonprofit secured new corporate revenue streams, expanded its funding to schools in other states across the country, and held the most successful fundraiser in its -15-year history.

Valerie’s career began as a writer for the late California Governor George Deukmejian.  She served the Governor in both of his terms of office and was appointed Deputy Director of Communications of the State Employment Development Department, the youngest deputy director in California history, and served in the administration of California Governor Pete Wilson for two years. Her leadership in government public relations was lauded in the Los Angeles Times and received myriad awards.  Valerie was an “Outstanding Young Woman of America” for three consecutive years and was noted in McCall’s magazine as an outstanding woman leader.

Valerie was also vice-president of a local PR firm where she directed media for candidates for office, professional athletes, nonprofits, and ballot measures.  She was advertising manager and social editor for Comstock’s magazine for 10 years. She served as director of corporate relations and foundations for the Salvation Army, and her fundraising expertise led to new corporate sponsors, new grants, and new key events.

An award-winning writer, publicist, and fundraiser, Valerie is an alumna of the University of Southern California, where she majored in journalism and political science.  She has been active in many causes, including serving as board president for the Sacramento SPCA, board member of Catholic Charities, the Salvation Army Sac Metro Advisory Board, and the Sacramento Hispanic Chamber of Commerce. Her community service includes the Neighborhood Wellness Center in Del Paso Heights, Mercy Foundation Community Council, Mercy Women"s Heart Health Council, Lincoln Club of Sacramento, National Latina Business Women Association Sacramento, and Rotary of Sacramento.

Since retiring Lin has volunteered with the North Lake Tahoe Boys and Girls Club where she lead a STEM program for elementary school-age children. She has also volunteered with the Humane Society of Truckee-Tahoe and with the Society of Women Engineers student chapter at the University of Nevada in Reno. She currently volunteers with the Emergency Warming Shelter in Truckee which serves the homeless population and stranded motorists in Truckee/North Tahoe during extreme weather conditions. She is an advocate for feline health and medicine which she supports at UC Davis Veterinary Medicine and through various cat rescue organizations in California and nationally.

Lin holds a Ph.D. in Electrical Engineering/Computer Science from Rice University, an M.S. in Applied Science/Engineering from UC Davis, and a Bachelor"s degree with Honors in Mathematics from UC Berkeley.

In 2011, Hong Kong native Spencer Leung moved to Thailand to launch the organic operation of a Thai agricultural seed company. He believed that demand for organic food would continue to expand, but he didn’t simply want to make money. He wanted to do something good.

So Leung applied to become a Rotary Peace Fellow. He became the first peace fellow to be sponsored by District 3450 (Hong Kong, Macao, Mongolia, and China), attending the Rotary Peace Center at Chulalongkorn University in Bangkok in 2013. The Chulalongkorn fellowship is a three-month certificate program for professionals who are already working in their field.

“The more I looked into it, the more I believed organic agriculture could be a powerful peacebuilding platform,” Leung says. “So I finished the course, quit my job, and used my own savings to start Go Organics.”

Go Organics also offers farmers an affordable cold storage unit that will keep crops fresh up to 10 days longer, opening up more market opportunities. The farmers can use microfinancing to purchase the unit, and Go Organics guarantees the sale of a certain amount of produce.

Go Organics has been working with the University of California, Davis, to introduce technologies to dry produce, such as a chimney solar dryer that is constructed from locally available items. A table covered in black cloth and a chimney wrapped in plastic create an air tunnel that can be used to dry agricultural products including fruits, vegetables, meat, fish, and coffee beans.

“Right now there’s a big issue with food safety and food security, and reports say up to one-third of food produced is wasted,” says Anthony Phan, a project analyst at the Horticulture Innovation Lab at UC Davis.

At the same time, global food production needs to increase dramatically to feed a growing population. Go Organics’ projects are supporting the “dry chain,” ensuring that foods can be dried properly and packaged safely.

The DryCards are credit card-size laminated papers with cobalt chloride humidity indicator strips to measure moisture in products. The farmer puts the card, along with the produce, in a sealed storage container such as a jar or plastic bag; an hour later, the indicator strip will have changed color to indicate the moisture level. Pink means the product is too wet, while blue means it is safe to package.

The traditional alternative to the DryCard is a digital moisture meter, but that requires electricity or batteries, which are not always available to small farmers. The cards can be manufactured for 10 to 25 cents, Phan says, and can be reused many times. In addition to testing produce and other foods, they can also be used to monitor the moisture level of seeds in storage to ensure healthy germination, improving yields.

This publication is a joint effort of the seven disciplines that comprise the Georgia Vegetable Team. It is comprised of 14 topics on tomato, including history of tomato production, cultural practices, pest management, harvesting, handling and marketing. This publication provides information that will assist producers in improving the profitability of tomato production, whether they are new or experienced producers.

Tomatoes are an important crop for Georgia growers; however, successful tomato production is not easily achieved. Tomato production requires highly intensive management, production and marketing skills, and a significant investment. Per acre cost of production is high, and yields can be severely limited by pest problems or environment. Tomato production is complex. Expertise in the areas of cultural practices, soils and fertility management, pest control, harvesting, post-harvest handling, marketing, and farm record keeping is crucial to profitable production.

The tomato (Lycopersicon esculentum Mill.) is the most widely grown vegetable in the United States. Almost everyone who has a garden has at least one tomato plant. They can even be produced in window box gardens or in single pots. Commercially, it is of equally great importance. From processing to fresh market, and from beefsteak to grape tomatoes, the variety and usefulness of the fruit is virtually boundless.

Tomatoes are members of the nightshade family and, because of this, were considered for many years to be poisonous. Indeed, many crops in this family contain highly toxic alkaloids. Tomatine occurs in toxic quantities in the tomato foliage but is converted enzymatically to a non-toxic form in the fruit. Because of these beliefs, the crop was not used for food until the 18th century in England and France. Tomatoes were introduced to the United States in 1710, but only became popular as a food item later in that century. Even as late as 1900, many people held the belief that tomatoes were unsafe to eat.

Use of the crop has expanded rapidly over the past 100 years. Today more than 400,000 acres of tomatoes are produced in the United States. The yearly production exceeds 14 million tons (12.7 million metric tons), of which more than 12 million tons are processed into various products such as soup, catsup, sauce, salsa and prepared foods. Another 1.8 million tons are produced for the fresh market. Global production exceeds 70 million metric tons. Tomatoes are the leading processing vegetable crop in the United States.

In field production, plants depend on the soil for physical support and anchorage, nutrients and water. The degree to which the soil adequately provides these three factors depends upon topography, soil type, soil structure and soil management.

For tomato production, proper tillage is crucial for adequate soil management and optimal yields. Land preparation should involve enough tillage operations to make the soil suitable for seedling or transplant establishment and to provide the best soil structure for root growth and development.

Tillage systems using the moldboard (“bottom” or “turning”) plow prepare the greatest soil volume conducive to vigorous root growth. This allows the development of more extensive root systems, which can more efficiently access nutrients and water in the soil. Discing after moldboard plowing tends to re-compact the soil and should be avoided.

If there is an abundance of plants or plant residues on the soil surface, discing or mowing followed by discing is usually advised prior to moldboard plowing. This should be done 6 to 8 weeks ahead of planting to bury residue and allow it to decay. Immediately prior to plastic mulch installation or transplanting, perform final soil preparation and/or bedding with a rotary tiller, bedding disc or a double disc hiller in combination with a bedding press or leveling board. This provides a crustless, weed-free soil for the installation of plastic mulch or the establishment of transplants.

Tomatoes are usually transplanted into plastic mulch on raised beds. A raised bed will warm up more quickly in the spring and therefore will enhance earlier growth. Since tomatoes do poorly in excessively wet soils, a raised bed facilitates drainage and helps prevent waterlogging in low areas or in poorly drained soils. Raised beds are generally 3 to 8 inches high. Keep in mind, however, that tomatoes planted on raised beds may also require more irrigation during drought conditions.

Soil organic matter consists of plant and animal residues in various stages of decay. Organic matter improves soil structure (helps to reduce compaction and crusting), increases water infiltration, decreases water and wind erosion, increases the soil’s ability to resist leaching of many plant nutrients, and releases plant nutrients during decomposition.

Planting tomatoes in reduced tillage situations has been tried with variable results in different parts of the country. Often cover crops can be killed with a burn down herbicide. Then tomatoes are either transplanted directly into the cover, or a narrow strip is tilled and prepared for transplanting while leaving the residue between rows. While these residues can protect the fruit from direct contact with the soil, currently the impediments outweigh the benefits for large-scale commercial production. Leguminous covers can provide nitrogen to the crop and there are certainly soil conservation advantages.

The primary encumbrance to success in reduced tillage systems is adequate weed and disease control. The application of phosphates, potash and lime are also more difficult in these systems, so reduced tillage is used only on a limited basis in commercial tomato production. With advances in weed and disease control technology, this type of production may become more feasible in the future.

In general, close windbreaks give the best wind protection and help moderate the tomato plants’ microenvironment and enhance earliness. Especially on sandy soils, windbreaks reduce damage from sandblasting of plants and small fruit during early spring. Sandblasting can be more of a problem with plastic mulch, as the soil particles are carried easily by the wind across the field. Many growers spread small grain seed after the plastic mulch is applied to reduce sand blasting. Windbreaks also conserve soil moisture by reducing direct evaporation from the soil and transpiration from the plant. This can enhance plant growth throughout the season.

To minimize insect migration to the tomato crop, destroy windbreak crops by herbicides, mowing and/or tillage before they lose their green color and begin to die back.

Seeding tomatoes directly into the field is not recommended due to the high cost of hybrid seed and the specific conditions required for adequate germination. Most tomatoes are transplanted to the field from greenhouse-grown plants. Direct seeding has other disadvantages: (1) Weed control is usually much more difficult with direct seeded than with transplanted tomatoes; (2) direct seeding requires especially well made seedbeds and specialized planting equipment to adequately control depth of planting and in-row spacing; (3) because of the shallow planting depth required for tomato seed, the field must be nearly level to prevent seeds from being washed away or covered too deeply with water-transported soil; and (4) spring harvest dates will be at least 2 to 3 weeks later for direct seeded tomatoes.

Typically, 5- to 6-week old tomato seedlings are transplanted into the field. As with most similar vegetable crops, container-grown transplants are preferred over bare root plants. Container grown transplants retain transplant growing medium (soil-substitute) attached to their roots after removal from the container (flat, tray). Many growers prefer this type transplant because (1) they are less subject to transplant shock, (2) usually require little, if any, replanting, (3) resume growth more quickly after transplanting, and (4) grow and produce more uniformly. Tomato plants produced in a 1-inch cell size tray are commonly used for transplanting. Many growers will use a 1.5-inch cell tray for transplant production in the fall when transplant stress is greater.

Set transplants as soon as possible after removing from containers or after pulling. If it is necessary to hold tomato plants for several days before transplanting them, keep them cool (around 55-65 degrees F if possible) and do not allow the roots to dry out prior to transplanting. When setting plants, place them upright and place the roots 3 to 4 inches deep. Setting plants at least as deep as the cotyledons has been shown to enhance plant growth and early fruit production and maturity. Completely cover the root ball with soil to prevent wicking moisture from the soil. Tomatoes grow best if nighttime soil temperatures average higher than 60 degrees F.

At transplanting, apply an appropriate fertilizer starter solution (see Fertilizer Management section). After transplanting (especially within the first 2 weeks) it is very important that soil moisture be maintained so that plant roots can become well established.

Tomatoes can be planted in one of many different arrangements that provide adequate space for plant growth. Often the spacing is based on the type of trellising and equipment that will be used in the field. The within-row and between-row spacings are selected to meet these limitations. The optimal plant population per acre may also be influenced by plant growth habit (compact, spreading), plant size at maturity (small, medium, large), vigor of specific cultivars, climate, soil moisture, nutrient availability, management system and soil productivity.

Select varieties on the basis of marketable yield potential, quality, market acceptability, adaptability and disease resistance or tolerance. The selection of a variety(ies) should be made with input from the buyer of the crop several months in advance of planting. Other characteristics to consider include maturity, size, shape, color, firmness, shipping quality and plant habit.

There are a plethora of commercially available tomato varieties, many of which will perform well under Georgia conditions. Varieties will perform differently under various environmental conditions. Yield, though ultimately important, should not be the only selection criteria. Tomatoes produced on plastic mulch with drip irrigation will commonly average more than 1,500 25-pound cartons per acre. Select varieties that have yield potential that equals or surpasses this average.

Plants also need to produce adequate foliage to protect fruit. Basically, a variety must be adaptable to the area, produce a competitive yield and be acceptable to buyers. Disease resistance will be most important with diseases for which there are no other good management options. Varieties produced in Georgia should be resistant to Fusarium wilt (Races 1 and 2) and Verticillium wilt (Race 1). In recent years, resistance to Tomato Spotted Wilt Virus has become equally as important, since varietal resistance is the most effective control method at this time. Other resistance of significance should include Gray Leaf Spot and Tobacco Mosaic Virus.

All commercially important tomatoes grown in Georgia belong to the species Lycopersicon esculentum. Table 1 lists those varieties that have performed well in Georgia or in similar areas of the southeastern United States. Notations in the disease resistance column indicate either resistance or tolerance. Some varieties may not exhibit complete resistance to the disease listed.

Most commercial determinate tomatoes are produced using short stake culture for trellising. This type of culture produces fruits that are higher in quality and easier to harvest and enhances spray coverage. In this system, stakes approximately 4 feet long and ¾ to 1 inch square are placed between every one or two plants depending on the tying system that is employed. Stakes are usually driven about 12 inches into the ground. An additional stake can be supplied at the ends of each section to strengthen the trellis.

Stake plants immediately after planting to minimize damage to the root system and to have the trellis ready when needed. Plants are usually tied initially when they are about 12-15 inches tall and should be tied prior to any plants lodging. The first string is usually placed about 10 inches above the ground. Subsequent tyings are placed about 6 inches above the previous one. Determinate varieties may be tied as many as three to four times.

Another system of tying involves placing a stake after every plant. The twine is then simply wrapped around each stake and along one side of the plant going along the row and around the other side of the plant coming back in the other direction on the opposite side of the row. Regardless of the system used, the twine should be held with enough tension to adequately support the plants. If the twine is too tight, however, it can impede harvest and damage plants and fruit.

Determinate tomatoes often still require some level of pruning. Pruning is the removal of suckers (axillary shoots). The degree to which pruning is needed will vary with the variety used but can impact yield and quality significantly. Plants that produce vigorous foliage that are not pruned will produce more, but smaller fruit. Pruning helps increase the size of the fruit. It can also enhance earliness of the crown set, reduce pest pressure and enhance spray coverage. In general, pruning will involve removal of one to all suckers up to the first fork (the sucker just below the first flower cluster).

Growers should experiment with individual varieties to determine the degree of pruning needed. Often the seed supplier can provide information on specific varieties regarding pruning. Some varieties require only the removal of ground suckers (at the cotyledons) or none at all. Overpruning can cause reduced yields and increased sunburn, blossom end rot and catfacing. More vigorous varieties may require the removal of ground suckers plus two additional suckers. Remove suckers when they are small (2 to 4 inches long). Removal of large suckers is more time consuming and can damage the plant. Prune before the first stringing to facilitate the process, since the strings may be in the way. A second pruning may be required to remove suckers that were not large enough to remove easily during the first pruning and to remove ground suckers that may have developed. Prune plants when the foliage is dry to reduce the spread of disease.

Media for production is usually peat based with various additives such as perlite and vermiculite to improve its characteristics. These can be purchased ready mixed or you can formulate your own mix. The individual components of peat moss, perlite, vermiculite, etc., can be purchased. Whether buying the individual components or a ready-made product, it is advisable to use finer textured media when starting seed. Check with your supplier about media texture. Some media are specially made for this purpose. In addition, these media may have fertilizer and wetting agents mixed in. Media with fertilizer is often referred to as charged.

After flats have been filled and the seed planted, they are often wrapped with plastic pallet wrap or placed in germination rooms (rooms with temperature and humidity tightly controlled) for 48-72 hours to ensure even moisture and temperature for optimum germination. The optimum germination temperature for tomatoes is 85 degrees F, at which tomato seedlings should emerge in about 5-6 days. See Table 2 for soil temperatures and number of days to germination.

If charged media is used, there will be no need for fertilizer for the first 3 to 4 weeks of production. After that, use 150-200 ppm of a suitable water soluble fertilizer once per week (Table 3). With media that has no premixed fertilizer, begin fertilization as soon as the plants emerge. Growers may wish to use as little as 50 ppm of a suitable water soluble fertilizer with every irrigation. Tomatoes will require approximately 5 to 7 weeks to produce a good quality transplant. Cooler temperatures will slow growth, so greenhouse temperatures should be kept above 60 degrees F at night to accelerate growth.

Take care when transplanting into black plastic so the plants do not touch the plastic. The plastic can absorb enough heat to injure and kill plants. A drench of about 0.5 pint of a suitable starter solution should be applied to each plant. Examples of suitable solutions include mixing 3 pounds of 11-34-0 or 18-46-0 fertilizer in 50 gallons of water. Most transplanting equipment will have a tank to hold the solution and will automatically dispense the solution to each plant.

The use of plastic mulch in the commercial production of staked tomatoes is almost universal in the south-east. Plastic mulch is used to promote earliness, reduce weed pressure, and to conserve moisture and fertilizer. Most often drip irrigation is used in conjunction with plastic mulch. There are both advantages and disadvantages to producing crops under this system.

Advantages: Plastic mulch promotes earliness by capturing heat, which increases soil temperatures and accelerates growth. Black plastic will prevent the establishment of many in-row weeds. Mulch will reduce fertilizer leaching from tomato beds and will conserve moisture by reducing soil surface evaporation.

Furthermore, where fumigants are used, plastic mulch provides a barrier that increases fumigant efficiency. Plastic mulch also keeps fruit cleaner by reducing soil spatter. When using drip irrigation particularly, disease is often reduced as the foliage stays drier and, again, soil is not splashed onto the plant.

Disadvantages: Specialized equipment is required to lay plastic mulch, which means increased variable costs for custom application or the purchase of this equipment. Yellow and purple nutsedges are not controlled by black plastic mulch, and suitable fumigants/ herbicides must be applied if nutsedge is a potential problem. The cost of plastic removal and disposal is an additional expense.

One to 1.25 mil black plastic is the cheapest and traditionally has been most often used in spring tomato production. Embossed plastic has a crimped pattern in the plastic that allows the mulch to stretch and contract so it can be laid snug to the bed. This can be important, particularly in multiple cropping operations where, for example, spring tomatoes may be followed by fall cucumbers. The embossed plastic is less likely to be damaged by wind and other environmental factors, thus increasing the potential for use on multiple crops.

Land preparation for laying plastic is similar to that described in the prior chapter on culture and varieties. The site should still be deep turned and rototilled. Usually a hipper is used to form a high ridge of soil down the middle of the bed to assure the bed pan is filled with soil. This creates a firm, full bed. The bed pan should leave a bed with a slight crown in the middle that slopes slightly to each side. This prevents water from standing on the plastic or being funneled into the holes and waterlogging the soil. Generally, fumigant is applied as the bed pan passes and plastic is installed just behind the pan. Drip tape is installed at the same time, just in front of the plastic, and should be buried 1 inch below the surface to prevent “snaking” under the plastic and to reduce rodent damage to the tape. Drip tape buried deeper will be difficult to remove and will not wet the upper portion of the root zone. Soil moisture should be good at the time plastic is installed to ensure a good, firm bed.

Most tomatoes are planted where fertigation with drip irrigation is used. In these cases all the phosphorous (P) and micronutrients, and one-third to one-half of the nitrogen (N) and potassium (K) should be incorporated into the bed before the plastic is laid. Apply the remaining N and K through weekly fertigations beginning just after transplant establishment. The rate of application of these fertigations will change with the stage of the crop.

Tomatoes are transplanted with a tractor mounted implement that uses a water wheel to punch holes in the plastic at the appropriate interval. A person (or persons) riding on seat(s) mounted behind the water wheel(s) places a transplant into the newly formed hole and covers the rootball. An alternate approach used by many producers is use of a water wheel or similar device to punch holes, with a crew of people walking the field and hand setting plants. The plants are then watered with a water wagon following the setting crews.

Irrigation studies in the southeast show that irrigation increases annual tomato yields by an average of at least 60 percent over dryland production. Quality of irrigated tomatoes is also much better. Irrigation eliminates disastrous crop losses resulting from severe drought.

Tomatoes are potentially deep rooted, with significant root densities up to 4 feet deep. In Georgia soils, however, the effective rooting depth is generally much less. Actual root depths vary considerably depending upon soil conditions and cultural practices. The effective rooting depth is usually 12 to 18 inches with half of the roots in the top 6 inches. It is important not to allow these roots to dry out or root damage will occur.

Moisture stress in tomatoes causes shedding of flowers and young fruit, sunscalding and dry rot of fruit. The most critical stages for watering are at transplanting, flowering and fruit development.

These systems include center pivot, linear move, traveling gun, permanent set and portable aluminum pipe with sprinklers. Any of these systems are satisfactory if they are used correctly. There are, however, significant differences in initial cost, fuel cost and labor requirements.

Drip irrigation has become the standard practice for tomato production. Although it can be used with or without plastic mulch, its use is highly recommended with plastic mulch culture. One of the major advantages of drip irrigation is its water use efficiency. Studies in Florida indicate that drip irrigated vegetables require 40 percent less water than sprinkler irrigated vegetables. Weeds are also less of a problem, since only the rows are watered and the middles remain dry. Some studies have also shown significant yield increases with drip irrigation and plastic mulch when compared with sprinkler irrigated tomatoes. The most dramatic yields have been attained by using drip irrigation and plastic mulch, and supplementing nutrients by injecting fertilizers into the drip system (fertigation).

The combined loss of water by evaporation from the soil and transpiration from plant surfaces is called evapotranspiration (ET). Peak ET rates for tomatoes are about 0.2 inch per day. Factors affecting ET are stage of crop growth, temperature, relative humidity, solar radiation, wind velocity and plant spacing. Transplant tomatoes into moist soil and irrigate with 0.3 to 0.5 inch immediately after transplanting to settle the soil around the roots.

Irrigation can best be managed by monitoring the amount of moisture in the soil. This can be done with soil moisture blocks. For best results on tomatoes, maintain soil moisture below 30 centibars. Drip irrigation systems need to be operated more frequently than sprinkler systems. Typically, they are operated every day or every other day. Do not saturate the soil with water, especially when using plastic mulch. Plastic mulch will tend to keep the soil from drying out and tomatoes grow poorly in waterlogged soil.

Blossom-end rot is a calcium deficiency that occurs at the blossom end of the fruit. It is characterized by black, necrotic, sunken tissue at the blossom end. Fruit with necrotic tissue is unsalable and the damage cannot be corrected. Although the tissue is calcium deficient, preplant applications of calcium or postplant applications to correct the disorder often have no effect.

To a certain extent, this problem can be alleviated with even moisture during plant growth. Wide swings from wet to dry conditions as well as overwatering tend to aggravate this problem. Exogenous applications of calcium as foliar sprays have been suggested to alleviate this problem. Any such application would have to occur prior to visible symptoms when fruit are just forming, but there is little evidence this is an effective practice.

Although tomatoes are warm season vegetables, they require relatively moderate temperatures to set fruit. Nighttime temperatures above 70 degrees F. will cause blossom drop, which in turn will reduce yields.

This problem is solved by planting at that time of year when night temperatures will be below this threshold during flowering and fruiting. Transplanting dates for south Georgia would be from March 1 to April 30 in the spring and from July 15 to August 15 in the fall. In north Georgia this would be from April 15 to June 15 in the spring and it is not recommended that tomatoes be grown in the fall. In addition to planting date, there are “hot set” tomatoes available. These tomatoes have been bred to set fruit under higher temperatures (see Table 1 for varieties). For fall planted tomatoes, hot set types are recommended.

Maintaining even moisture conditions, avoiding excessive pruning, and having a heavy fruit load will help prevent this problem. Variety selection can also help alleviate this problem. Varieties are available that are resistant to cracking. Generally, cracking susceptible varieties will crack when fruit are still in the green stage, whereas resistant varieties often don’t show cracking until later, when the fruit is turning color.

Concentric cracking is also caused by rapid growth, but generally occurs when there are alternating periods of rapid growth followed by slower growth. This can occur with wet/dry cycles or cycles of high and low temperatures. Generally this type of cracking occurs as fruit near maturation. Even moisture throughout the growing period will help alleviate this problem. Also avoid fertilization spikes that encourage cyclic growth.

Zippering may be related to catfacing, only the damage occurs in straight lines from the blossom end to the stem end. The line may have a calloused or corky appearance.

Tomato fruit may develop a papery thin area on the fruit that will appear tan or white in color. This is caused by sunscald, where the area affected is exposed to intense sunlight and heat resulting in a breakdown of the tissue. Sunscald may also appear as hard yellow areas on the fruit that are exposed. Maintaining good foliage cover during fruit development and avoiding excessive pruning will minimize this problem.

Occasionally, a tomato will exhibit white tissue in the crosswalls when cut. This is rarely seen when fruit are harvested at the mature green stage, but it can be a problem with vine ripe fruit. It is unclear what causes this, but adequate potassium fertilizer appears to reduce the problem.

Rain check is the formation of tiny transverse cracks on the fruit. These cracks may heal, forming a rough texture on the fruit; generally these fruit are unmarketable.

As with many of these disorders, it is unclear what causes this, but it is associated with rain events. Heavy rains following dry periods are times when this is most likely to occur. This phenomenon may be related to other types of cracking and may be alleviated with growing conditions that don’t encourage wet/dry cycles.

Lime and fertilizer management should be tailored to apply optimal amounts of lime and nutrients at the most appropriate time(s) and by the most effective application method(s). Fertilizer management is impacted by cultural methods, tillage practices and cropping sequences. A proper nutrient management program takes into account native soil fertility and residual fertilizer. Therefore, the first step in an appropriate fertilizer management program is to properly take a soil test 3 to 5 months before the crop is to be planted.

Adjusting the soil to the appropriate pH range is the first consideration for any fertilizer management program. The soil pH strongly influences plant growth, the availability of nutrients, and the activities of microorganisms in the soil. It is important to keep soil pH in the proper range in order to produce the best yields of high quality tomatoes. Soil tests results indicate soil pH levels and also provide recommendations for any needed amounts of lime required to raise the pH to the desired range.

The optimum pH range for tomato production is 6.2 to 6.8. Most Georgia soils will become strongly acid (pH 5.0 or less) with time if lime is not applied. Continuous cropping and application of high rates of nitrogen reduce pH at an even faster rate. Lime also adds calcium and, with dolomitic lime, magnesium to the soil.

The two most common liming materials available in Georgia are calcitic and dolomitic limestone. Dolomitic limestone also contains 6 to 12 percent magnesium in addition to calcium. Since many soils, and particularly lighter Coastal Plains soils, routinely become deficient in magnesium, dolomitic limestone is usually the preferred liming material.

Recommending a specific fertilizer management program universal for all tomato fields would result in applications that are inefficient and not cost effective. In addition to crop nutrient requirements and soil types, fertilizer recommendations should take into consideration soil pH, residual nutrients and inherent soil fertility. Therefore, fertilizer recommendations based on soil test analyses have the greatest potential for providing tomatoes with adequate but not excessive fertility. Applications limited to required amounts result in optimum growth and yield without wasting fertilizer or encouraging luxury consumption of nutrients, which can negatively impact quality or cause fertilizer burn.

Recommendations based on soil tests and complemented with plant tissue analyses during the season should result in the most efficient lime and fertilizer management program possible. Valid soil sampling procedures must be used to collect the samples submitted for analyses, however. To be beneficial, a soil sample must reliably represent the field or “management unit” from which it is taken. Soil samples that are improperly collected, compiled or labeled are of dubious benefit and may actually be detrimental. If you have questions about soil sampling, please contact your local county extension office for information.

In addition to lime application, preplant applications and in-season supplemental applications of fertilizer will be necessary for good crop growth and yield. In general, preplant applications are made prior to installation of plastic mulch. Research shows that broadcasting over the entire field is usually less effective than banding. An acceptable alternative to field broadcasting and one that is most often used with plastic mulch production is the “modified broadcast” method, where the preplant fertilizer containing a portion of the nitrogen and potassium, and any recommended phosphorous and micronutrients, are broadcast in the bed area only.

In addition to supplying phosphorus, which may be inadequately available (especially in cold soils in the early spring), the starter solution supplies water and firms the soil around roots. This helps eliminate air pockets that can cause root drying and subsequent plant or root damage. A starter solution is no substitute for adequate rainfall or irrigation after transplanting, however.

Be careful to mix and apply starter fertilizer according to the manufacturer’s recommendations. If the starter solution is too highly concentrated (mixed too strong), it can kill plant roots and result in dead or stunted plants. When mixing and applying from a large tank, mix a fresh solution only after the tank becomes empty. This helps prevent the gradual increase in concentration that will occur if a portion of the previous mix is used for a portion of the water component in subsequent batches. If a dry or crystalline formulation is used, be sure it is thoroughly mixed and agitated in the tank, since settling can result in streaks of highly concentrated application that can stunt or kill plants.

Table 4 indicates the pounds of fertilizer nutrients recommended for various soil P and K levels according to University of Georgia soil test ratings of residual phosphorus (P2O5) and potassium (K2O).

One-third to one-half of the potassium should either (1) be incorporated into the bed prior to installing plastic mulch, or (2) be applied in two bands, each located 2 to 3 inches to the side and 2 to 3 inches below the level of plant roots for bare ground production. The remainder of the recommended potassium should be applied through the drip system according to the schedule in Table 5 or, for bare ground culture, in one to three applications as needed. It can be banded in an area on both sides of the row just ahead of the developing root tips. The maximum number of applications is usually more effective on sandy soils.

For typical Coastal Plains soils, one-third to one-half of the recommended nitrogen should either (1) be incorporated into the bed prior to plastic installation or, (2) with bare ground culture, applied in two bands, each located 2 to 3 inches to the side and 2 to 3 inches below the level of plant roots. Apply the remaining recommended N through drip irrigation according to the schedule in Table 5. On bare ground, one to three side dressed applications (possibly four to five applications for extended harvest period on very sandy soil) are needed. It can be banded in an area on both sides of the row just ahead of the developing root tips. For heavier Piedmont, Mountain and Limestone Valley soils, one to two applications are usually sufficient.

Table 5. An example fertilizer injection schedule for a Coastal Plains soil that is low in potassium. The schedule is for a 14-week crop. Extended harvests will require additional injection applications.

If the soil test indicates magnesium is low and if lime is recommended, apply dolomitic limestone. If magnesium is low and lime is not recommended, apply 25 pounds of elemental magnesium per acre. Apply a minimum of 10 pounds of sulfur per acre and, if soil test indicates low, apply 1 pound of actual boron per acre and 5 pounds of actual zinc per acre. These nutrients should be supplied in the pre-plant fertilizer application.

The fact that plants can absorb some fertilizer elements through their leaves has been known for some time. Leaves of many vegetable plants, however, are not especially well adapted for absorbing nutrients because of a waxy cuticle. In some instances, plants that seem to benefit from foliar uptake are actually benefitting from nutrient spray that reaches the soil and is taken up by roots.

The crucial question is whether or not foliar N, P or K actually increases yield or enhances quality. Although some growers feel that foliar fertilizer should be used to supplement a soil applied fertilizer program, research findings do not support this practice. If proper fertilizer management of soil applied nutrients is used, then additional supplementation by foliar fertilization is not usually required.

Foliar nutrients are often expected to cure a variety of plant problems, many of which may be unrelated to nutrition. They include reducing stress induced blossom drop, aiding in healing frost or hail damaged plants, increasing plant resistance to various stresses and pests, etc. Nutrients are only effective as long as they are supplying a nutritional need, but neither soil-applied nor foliar-applied nutrients are panaceas.

Quite often after frost or hail occurs, tomato growers apply foliar nutrients to give the plants a boost to promote rapid recovery. If a proper fertilizer program is being used before foliage damage, tomato plants don’t need additional fertilizer. What they do need is time and the proper environment for the normal recovery processes to occur. In addition, the likelihood of significant nutritional benefits from a foliar application of fertilizer to plants that have lost most of their leaves (or have a large proportion of their leaves severely damaged) is questionable.

Foliar application of sulfur, magnesium, calcium and micronutrients may help alleviate deficiencies. They should be applied, however, only if there is a real need for them and only in quantities recommended for foliar application. Application of excessive amounts can cause fertilizer burn and/or toxicity problems.

Plant tissue analysis or petiole sap analysis is an excellent tool for measuring the nutrient status of the crop during the season. Particularly with fertigation, it is simple to adjust fertilizer injection rates according to the analysis results. Sufficiency ranges for tissue analysis are in Tables 6 and 7 and are for first flower stage and first ripe fruit stage, respectively, with the sample taken from the most recently mature leaf. Fresh sap can be pressed from the petioles of tomato plants and used to determine nitrogen and potassium nutritional status. Sufficiency ranges for these are listed in Table 8.

Olson, S.M., D.N. Maynard, G.J. Hochmuth, C.S. Vavrina, W.M. Stall, M.T. Momol, S.E. Webb, T.G. Taylor, S.A. Smith, and E. H. Simmone. 2005. Tomato Production in Florida in Vegetable Handbook for Florida 2005-2006. Edited by S.M. Olson and E.H. Simmone. Univ. of Florida IFAS Extension. Gainesville, Fla. pp. 357-362.

The equipment used for applying liquid insecticides, fungicides, herbicides and foliar fertilizers are classified as sprayers. Basically, there are two types of sprayers recommended for spraying tomatoes — hydraulic and air-curtain boom. The key to maximum coverage with insecticide and fungicides is the ability of the air within the plant canopy to be replaced with pesticides.

The concept of this approach is to increase the effectiveness of pest-control substances, provide better coverage to the underside of leaves, promote deeper penetration into the crop canopy, make it easier for small droplets to deposit on the target, cover more acres per load, and reduce drift.

Studies conducted by the USDA Agricultural Research Service in Stoneville, Mississippi, have shown that the air-assisted sprayers tended to show improved insect control in the mid to lower canopies. The air stream tended to open the canopy and help spray particles penetrate to a deeper level. Mid- to lower-canopy penetration and coverage is important when working with insecticides and fungicides, but may not be as critical when applying herbicides.

Most materials applied by a sprayer are a mixture or suspension. Uniform application demands a uniform tank mix. Most boom sprayers have a tank agitator to maintain uniform mixture. The agitation (mixing) may be produced by jet agitators, volume boosters (sometimes referred to as hydraulic agitators) and mechanical agitators. These can be purchased separately and put on sprayers. Make sure an agitator is on every sprayer. Some growers make a mistake of not operating the agitator when moving from field to field or when stopping for a few minutes. Always agitate continuously when using pesticides that tend to settle out.

When applying insecticides and fungicides, use solid or hollow cone type nozzles. The two patterns that are developed by solid or hollow cone nozzles can be produced by different tip configurations. One type tip, disc-n-core, consists of two parts. One part is a core (swirl plate) where the fluid enters and is forced through tangential openings. Then a disc-type hardened stainless steel orifice (opening) is added. Another type of tip that produces the same patterns is of one-piece construction (nozzle body). Liquid is passed through a precision distributor with diagonal slots that produce swirl in a converging chamber. The resulting pattern of both tip configurations is either solid or hollow cone. Even fan and hollow cone nozzles can be used for banding insecticide or fungicides over the row.

When applying insecticides and fungicides, it is advantageous to completely cover both sides of all leaves with spray. When spraying tomatoes, use one or two nozzles over the top of the row (up to 8 inches wide). Then as the plants start to grow and bush, adapt the nozzle arrangement for the various growth stages of plants (Figures 3 and 4). Opposing nozzles should be rotated clockwise slightly so that spray cones do not collide. This will guarantee that the spray is applied from all directions into the canopy. As the plant increases in height, add additional nozzles for every 8 to 10 inches of growth. In all spray configurations, the nozzle tips should be 6 to 10 inches from the foliage. Properly selected nozzles should be able to apply 25 to 125 gallons per acre when operating at a pressure of 60 to 200 or higher psi. Usually, more than one size of nozzle will be needed to carry out a season-long spray program.

Bacterial spot is the most common and often the most serious disease affecting tomatoes in Georgia. This disease is caused by the bacterium Xanthomonas axonopodispv. vesicatoria. Bacterial spot lesions can be observed on leaves, stems and fruit and occurs during all stages of plant growth. Leaf lesions usually begin as small water-soaked lesions that gradually become necrotic and brown in the center (Figure 5). During wet periods the lesions appear more water-so