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What Is Olive Knot: Information On Olive Knot Disease Treatment

What Is Olive Knot: Information On Olive Knot Disease Treatment


By: Amy Grant

Olives have become more heavily cultivated in the United States in recent years due to their increasing popularity, specifically for the health benefits of the fruit’s oil. This increasing demand and resulting swell in production has also brought about increased incidence of olive knot. What is olive knot and what other olive knot disease info might be helpful in treating olive knot? Read on to learn more.

What is Olive Knot?

Olive knot (Olea europaea) is a disease caused by the pathogen Pseudomonas savastanoi. This pathogen is known as an epiphyte. ‘Epi’ is from the Greek, meaning ‘upon’ while ‘phyte’ means ‘upon the plant.’ Thus, this pathogen thrives on the rough bark of the twigs rather than the olive’s leaves.

As the name suggests, olive knot presents itself as galls or “knots” at infection sites, usually but not always, at leaf nodes. Pruning or other wounds can also open the plant up for infection by the bacterium and freeze damage increases the disease’s severity.

When it rains, the galls ooze infectious bacterial goo that can be transmitted to uninfected plants. Infection develops in the spring and early summer and produces galls ½ to 2 inches within 10-14 days.

All cultivars of olive are susceptible to olive knot, but only the above portions of the tree are affected. Severity of the infection varies from cultivar to cultivar, but young, one-year-old plants are much more susceptible than older olives.

Additional Olive Knot Disease Info

While this disease has been witnessed worldwide throughout olive growing regions, the increase in cultivation, especially in northern California, has made it a more common and serious threat.

Northern California’s mild climate and prevalent rainfall combined with mechanized cultural practices on large olive plantings has become the perfect storm and thrust the disease into the forefront as one of the more potentially costly diseases of the olive. The galls girdle and kill off afflicted twigs which, in turn, reduces yield and affects fruit size and quality.

For the home olive grower, while the disease isn’t fiscally damaging, the resulting galls are unsightly and detract from the beauty of the landscape. Bacteria survive in the knots and are then spread throughout the year, making control of olive knot disease especially difficult. So how do you go about treating olive knot?

Is There an Olive Knot Treatment?

As mentioned, control of olive knot disease is difficult. If the olive already has olive knot, carefully prune out the afflicted twigs and branches during the dry season with sanitized shears. Disinfect them every so often as you prune to mitigate the possibility of spreading the infection.

Combine the above olive knot treatment with an application of copper containing bactericides to leaf scars and other injuries to minimize the possibility of contamination. A minimum of two applications is needed, one in the fall and one in the spring.

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The olive (Olea europaea) is a long-lived evergreen tree native to the Mediterranean. The tree has been cultivated and cherished by humans for thousands of years, thanks to its edible drupes and graceful appearance. When grown in the proper cultural conditions, olive trees are usually hardy, resilient trees. Unattractive bumps on the branches and stems of an olive are most likely the result of a bacterial disease called olive knot, though armored scale insects might also be to blame.


Best Practices for Growers

These Best Practices are based on California research conducted by UC Davis, UC Cooperative Extension (UCCE) and UC Agricultural and Natural Resources (ANR).

They were prepared by the UC Davis Olive Center and G. Steven Sibbett, UCCE Farm Advisor Emeritus, Dr. Louise Ferguson, ANR Extension Specialist and Dr. Elizabeth Fichtner, UCCE Farm Advisor. We recommend that growers also review comprehensive research information available through ANR, including the Olive Production Manual, Organic Olive Production Manual and UC IPM Online.

Siting an Olive Orchard

It is critical to assess climate before planting olives in a particular site:

  • Winter. Ideally, winter temperatures should fluctuate between 35 °F (2 °C) and 65 °F (18 °C). Temperatures below freezing cause progressively more tree damage, from small shoot and branch lesions that provide entry points for olive knot bacteria at 23 °F to 32 °F (-5 °C to 0 °C), greater tissue damage at 14 °F to 23 °F (-5 °C to -10 °C) and death of large limbs and entire trees at temperatures below 14 °F (-10 °C).
  • Spring. The bloom development period should be free of prolonged cold and wet or hot and dry weather. These conditions hinder flower development, pollination, fertilization and fruit set. Long or sudden cold spells particularly increase the negative impact.
  • Summer. Long, warm and dry summers promote good fruit development. Avoid areas with summer rainfall and high humidity, which promote fungal and bacterial diseases.
  • Fall. Temperatures below freezing often damage processing quality of fruit destined for either table or oil. Pay special attention to low-lying areas, which are especially vulnerable to colder temperatures. Fall rains improve size and value of fruits destined for table processing, but make fruit destined for oil processing more susceptible to damage, fermentation and mold and may contribute to emulsions that hinder oil extraction Rains at harvest can also hinder mechanical harvest equipment from accessing the orchard.

Research the site history. Find out crop history from the previous landowner and, where relevant, the local agricultural commissioner’s office. Avoid soil previously planted with crops (such as cotton, cucurbits, eggplant, peppers, potato, or tomato) susceptible to the Verticillium wilt fungus, a soil-borne disease that kills olive trees. There are limited Verticillium wilt management strategies available to growers.

Analyze the soil profile. Managed correctly, olives perform well in many soils, even those considered marginal in quality. Soil maps do not provide sufficient detail for specific orchard sites. Use a backhoe or augur and dig pits in representative places on the planting site. Examine the soil’s physical condition, including layers that are texturally different, to identify limitations on root and water penetration. Olives do not grow well in poorly drained soils. The best and most productive soils are those un-stratified, moderately fine-textured of at least 4 ft (1.2 m) in depth.

Determine the soil chemistry. Take a representative soil sample from the orchard site and submit it to a laboratory for analysis. The best soils are those moderately acid to moderately alkaline (pH between 6.5 to 8.5). Soil below pH 5.5 can have aluminum and manganese toxicity, while soil above pH 8.5 have poor structure and may have sodium toxicity. Avoid soils high in salinity (≥4 dS/m). To avoid water penetration problems due to poor soil structure, avoid soils with an exchangeable sodium percentage of > 4 or be prepared to amend such soils to leach excessive sodium.Avoid soils with excessive boron (≥2 ppm), and chloride (10-15 meq/l) as these conditions may reduce productivity unless corrected or managed with soil amendments requiring additional expense.

Assess water availability. Although olive trees are drought tolerant, they will grow faster and produce more consistently in California with supplemental irrigation. Supplemental irrigation water can be available as irrigation district water (surface water) or by farm wells. Sites served only by irrigation districts are at risk of water shortage during drought years.Inadequate water during floral development can lead to poor fruit set especially if adverse weather occurs during or shortly after bloom. Inadequate water through the growing season can limit fruit size for table olive growers. Choose sites that can supply olive trees with approximately three acre-feet per year for table olives and two acre-feet per year for oil olives, although more water will be necessary if irrigation efficiency is compromised by conditions such as runoff or poor weed control.

Evaluate water quality. Knowing the site’s water chemistry will help growers manage chemical hazards and avoid excessive fertilizer use that increases orchard maintenance cost, reduces productivity and potentially pollutes water sources. Excessive sodium in water supplies concentrate in soil, causing infiltration problems. High nitrogen levels produce excessive vegetative growth hindering fruit production, encourages pest development (e.g. black scale) and adds additional pruning expense. Take a water sample and request a qualified laboratory to conduct an analysis of the elements in this table.

WATER ANALYSIS LIMIT
Acidity/alkalinity (pH) 6.5 – 8.5
Electrical conductivity (ECw) 0.80
Calcium (%) > 1.0
Magnesium (%) > 0.10
Manganese (ppm) > 20
Zinc (ppm) unknown
Copper (ppm) > 4
Boron (ppm) 14 19 - 150 > 185
Sodium (%) > 0.20
Chlorine (%) > 0.50

Avoid applying fertilizers if leaf tissue nutrient levels are adequate. Excessive fertilization increases production costs, nutritional imbalances and environmental pollution.

Fertigation, the application of fertilizers dissolved in irrigation water, is the most efficient fertilizing method. Fertigation delivers nutrients to areas of greatest root activity and density, maximizing a tree’s nutrient absorption. Fertigation requires cleanliness and irrigation system maintenance, because some fertilizers can clog the system. Fertigation with some fertilizers can also increase soil salinity.

Organic fertilizers such as compost or cover crops have advantages in releasing nutrients slowly year-round, developing soil structure and aiding water infiltration, but also may require additional water (e.g. for a cover crop). Any fertilizer can leach nutrients during cold and rainy periods (when trees are not taking up nutrients) and allow nitrogen runoff into water resources.

Pests

The primary olive pests in California are Olive Fly and Black Scale. For more information on olive pests, see UC Integrated Pest Management.

The larva of olive fly, Bactrocera oleae (Gmelin), feed on olive fruit, leading to losses for table olive growers and potentially imparting a defective flavor to olive oil. Olive fly can be controlled but not eradicated in California.

Monitor olive fly with either yellow sticky traps containing a sex pheromone and/or ammonium carbonate, ammonium bicarbonate, or diammonium phosphate bait or with MacPhail traps containing yeast hydrolosate and the same ammonia-producing chemicals as used with yellow sticky traps.

Control olive fly populations by collecting and destroying fruit on the ground and in trees after harvest, by use of bait sprays, and by “attract and kill” devices. Use Danitol late in the season if heavy infestations emerge after the summer. See more information about olive fly control here.

Black scale, Saissetia oleae (Olivier), feeds on olive leaves and twigs and excretes sugary honeydew that supports sooty mold growth impairing photosynthesis. Black scale infestation can reduce fruit bud formation, cause leaf drop and twig dieback and reduce the crop in the following year.

Monitor black scale in April by checking the inner canopy of about 40 trees per block for honeydew droplets on the leaves, and in May by checking at least 10 branches on 10 trees per 10-acre section for adult scale. Examine the terminal 20 inches of the branches, count the number of scale, and calculate the average per branch for the 10 trees.

Control black scale by pruning the trees to open up the canopy in the trees’ center. Heavy infestations (more than four scale per branch) also treat with insecticide in-season. See more information here.

Diseases

Primary olive diseases in California are Olive Knot, Olive Leaf Spot (“Peacock Spot”), and Verticillium Wilt. For more information on olive diseases, see UC IPM.

Olive knot, Pseudomonas syringae pv. savastanoi (Smith 1908), is a bacterial disease that produces galls (knots) on twigs and small branches at wounds, even minor wounds such as leaf scars. Cracks in bark caused by freeze injury can also lead to severe damage from olive knot. Cultivars that are sensitive to freezing (such as Manzanillo) are more susceptible to olive knot. The disease can kill young trees, reduce productivity in more mature trees, and produce off-flavors in the fruit.

Infection almost always occurs with moisture, particularly rain but also humid conditions, and can be carried by pruning shears and harvest equipment.

Copper has traditionally been used to control olive knot but has had inconsistent and diminishing effectiveness in recent years. UC research is underway to identify new methods of control, and new chemicals are in the registration process. See more information here.

Olive Leaf Spot (“Peacock Spot”)

This fungal disease is caused by Spilocea oleaginea (Cast.) Hughes. Lesions most commonly appear on upper leaf surfaces, beginning as tiny sooty blotches and progressing to green or black spots, with some lesions developing a yellow halo, thus the name Peacock Spot. Infected leaves drop prematurely, weakening small wood and reducing productivity.

Most infections occur during the coldest part of the California winter, and it may take several years before the disease causes economic loss.

Control Peacock Spot by a spraying a copper-containing fungicide, once in late fall before winter rains begin. See more information here.

Verticillium wilt, Verticillium dahlia Kleb., is a soil-borne fungus infecting a wide range of crops grown in California, including cotton, melon, pepper, pistachio, stone fruit and tomato, and some indigenous weed species. The fungus persists in soil as microsclerotia, which resemble small grains of sand. Leaves suddenly collapse and die on one or more branches soon after the first warm summer weather, reducing productivity significantly.

There is no control method available for Verticillium Wilt. Conduct a soil test for microsclerotia prior to establishing a new orchard. Previously planted crops that harbor the Verticillium Wilt fungus are likely to leave high levels of microsclerotia. See more information here.

Weeds

Weed management is essential for increasing orchard productivity (by eliminating competition for water and nutrients and increased frost protection, for example), facilitating harvest, removing fire hazards, and eliminating habitat for damaging insects and rodents.

The proper weed management strategy depends on many factors including weed species, soil type, irrigation method, amount of control desired and organic certification. Strategies include hand-weeding, mowing, disking, mulching, weed fabric, and spraying with pre-emergent and post-emergent herbicides.

Groves in the San Joaquin Valley are almost exclusively weed-free. Most California olive growers manage weeds by mowing the row middles and spraying herbicide in the tree row. Weed management is significantly more expensive in organic orchards. Begin weed management in new orchards to speed tree growth and productivity. See more information on weed management.

Fruit Thinning

Reducing the fruit load (thinning) in heavy crop years may be necessary to achieve adequate table olive size and mitigate alternate bearing.

Chemical thinning is the most useful fruit thinning tool available to table olive growers. Post-bloom application of naphthalene acetic acid (NAA) regulates crop size to improve fruit size and results in better shoot growth for return bloom the following year.

Pruning is not ideal as a thinning method because pruning removes both leaves and fruit (leaf-to-fruit ratio is an important factor in fruit size). In addition, pruning is labor intensive. Pruning is, however, the most traditional method and is useful when chemical fruit thinning is not practiced or available.

Hand thinning is an effective method but is too labor intensive to be practical for most growers. When hand-thinning, wear gloves to protect fingers. Strip fruit from trees with both hands but be careful not to damage or remove leaves. Thin the twigs from which at least five or six olives can be removed from one pull. Complete within four weeks of full bloom.

Pruning and Harvesting

Prune to optimize orchard productivity, mitigate alternate bearing, facilitate efficient fruit removal, manage crop size, rejuvenate productivity in older trees, reduce pests and disease, and reduce damage from mechanical harvesters.

Prune in spring and summer after winter rains have passed, to minimize diseases such as olive knot, attacks by pests, and susceptibility to freeze damage.

How a tree is trained and pruned is determined by the olive’s natural growth and crop-bearing pattern. Olives have “apical dominance,” where the central stem grows more strongly than lateral stems. The apical stem, which is vegetative rather than fruiting, produces several lateral buds that are almost exclusively fruiting buds. The two kinds of pruning cuts, heading and thinning, produce a different result with this apical vegetative and lateral fruit-bearing pattern:

  • Heading cuts decrease apical shoot growth by removing the apical vegetative bud and may stimulate latent lateral vegetative growth further back on the shoot. If the tree is vigorous and the heading cuts are severe this strong response could be exclusively vegetative and therefore delay fruit production for two years beyond pruning.
  • Thinning cuts remove a shoot where it emerges from the branch, producing a much weaker vegetative response and allow more light interception than heading cuts.

Moderate hedging cuts on alternate sides of the tree in alternate years will reduce the response of vegetative and fruiting shoots to produce consistent annual crops, thereby mitigating the alternate bearing tendency of many olive cultivars. Trees should be mechanically topped annually to maintain tree size and maximize fruit production on the lower lateral canopy (topping less frequently has been demonstrated to produce strong vegetative growth responses and erratic fruit production.)

Hand-harvesting.Hand-harvested orchards can be assisted with hand-held implements, hand-held pneumatic rakes, hand-held limb shakers, and by beating the trees with poles.

  • Prune to achieve a lobular shape when viewed from above and to allow light channels into the trunk so that growth and fruiting is not restricted to the outer shell.
  • Prune to maintain a safe tree height below 18 feet so that harvesters do not have to climb too high on ladders.
  • Prune nonproductive parts of the tree, or not at all, during light-crop years, to minimize crop loss. Pruning can be more severe in heavy crop years but does not result in larger fruit desired by table-olive growers since fruit size is largely determined on each branch by leaf-to-fruit ratio.
  • Prune mature trees from traditional orchards over several years so as to not dramatically reduce crop and stimulate excessive non-fruiting growth.
  • Harvest by sliding a cupped, protected hand down an olive shoot in a milking action, removing olives into a container or onto a tarp. Avoid removing leaves as to minimize the potential for disease, and avoid stepping on olives in tarps.

Trunk-shaking equipment.

Trunk-shaking equipment includes side-by-side harvesters and umbrella trunk shakers. These harvesters operate most efficiently when the orchard is young enough that the shaking provides efficient fruit removal. Eventually the efficiency of trunk shaking will be reduced as the trunk grows thicker, making it necessary for the grower to switch to other harvest methods, such as limb-shaking or canopy-contact equipment.

  • Direct the growth into stiff upright scaffolds, which efficiently transmit the shaking force. Top the trees at no more than 12 feet with scaffolds having no more than a 45° angle from the trunk. Prune with a combination of mechanical hedging and topping (or a single, gabled cut) with additional hand pruning to remove lateral branches extending from the scaffolds at less than a 45° angle.
  • Decrease canopy density with hand thinning cuts, as a heavier canopy will dampen shaking and decrease removal efficiency.
  • Prune generally to a V-shape with visibly filtered light.
  • Remove branches extending laterally into the row middle, which can reduce harvester efficiency.
  • Prune annually. If using a double-sided mechanical pruner, the annual pruning schedule can be every other row middle every other year. If using single-sided mechanical pruner, prune alternate tree row sides on alternate years. Top all trees annually.

Limb-shaking equipment. Limb-shaking equipment

  • Prune to establish a maximum of five well-spaced, upright scaffold branches (more that five scaffold branches increases the harvest time for each tree).
  • Decrease canopy density with hand-thinning cuts, as a heavier canopy will dampen shaking and decrease removal efficiency.
  • Remove branches extending laterally into the row middle, which can reduce harvester efficiency.

Canopy-contact equipment. Canopy-contact harvesters come with one of two mechanisms. Some compress and agitate the canopy with a series of horizontal bars called bow rods, while others have a head with vertical rows of radiating tines that extend into the canopy and remove the olives with a horizontal whipping motion. Both removal methods remove the fruit on the outer canopy more efficiently than interior fruit, but, unlike trunk-shaking equipment, it is not necessary to thin the canopy as the removal force is applied directly to the canopy.

  • Super-high-density (SHD) orchards in California typically have hedgerows spaced at 5-6 feet within the row and 12-13 feet between rows. High-density (HD) orchards with hedgerows spaced at 8-10 feet within the row and 16-18 feet between rows have been demonstrated to be optimal for harvesting and yield for California table olives.
  • Train the tree into an upright narrow canopy, with primary scaffolds parallel to the tree row and with shorter branches extending into the row middle, to facilitate production of a continuous, flat, fruiting wall.
  • Train SHD orchards to an espalier within the row. This can be accomplish by tying to a trellis or by simply weaving the branches through the trellis wires when adequately stiff. Train HD orchards to no more than 12 feet high after a season’s growth, 6 feet wide from row middle to row middle, with the bottom of the canopy 4 feet from the ground. Canopy width within the row will be a function of tree spacing within the row.
  • Remove branches, which can reduce harvester efficiency and damage harvest equipment, and will probably be broken by the harvester.
  • Prune annually. If using a double-sided mechanical pruner, the annual pruning schedule can be every other row middle every other year. If using single-sided mechanical pruner, prune alternate tree row sides on alternate years. Top all trees annually.


Olive knot is a bacterial disease that is spread by water and enters the tree through pruning cuts, cracks or wounds on the tree. Galls up to 2 inches in diameter appear on the tree. The galls restrict the movement of food and water through the tree, causing parts of the tree to starve and die. As shoots die back, the leaves dry and fall from the tree. Applications of bactericides containing copper before fall rains or when the tree is wounded will help prevent the disease. A gall eradicant paint can be used to treat infected trees.

Root rot occurs in soils that have poor drainage or are excessively wet. The rot is caused by fungal organisms living in the soil. Because the roots are no longer feeding the tree, tree growth is stunted and the foliage becomes sparse. To check for root rot, remove soil to expose the crown or roots of the tree. Scrape off about a 1-inch sliver of bark. If the exposed tissue is brown or black, the root is dead. The tree will most likely die in one or two years.

Jill Kokemuller has been writing since 2010, with work published in the "Daily Gate City." She spent six years working in a private boarding school, where her focus was English, algebra and geometry. Kokemuller is an authorized substitute teacher and holds a Bachelor of Arts in English from the University of Iowa.


Comments on the Disease

Sources of inoculum for this disease are rachises, shoots, and petioles killed by B. dothidea during the previous growing season that remain on the trees. Cankers can also provide inoculum for as long as 6 years.

Inoculum of the fungus can also originate from other sources, such as neighboring perennial crops and native plants, because the pathogen is capable of infecting a wide range of plants. Spores from these sources, which are released and spread during or shortly after rains, or triggered by sprinkler irrigation, cause primary infections on the vegetative and flowering buds.

Pruning injuries are the primary point of infection, but other causes of cankers and wood necrosis such as sunburn, mechanical injury, and galls caused by the olive knot bacterium Pseudomonas syringae pv. savastanoi, can also lead to infection by B. dothidea. The pathogen is also spread by birds and hemipteran insects.

B. dothidea can cause latent infections on buds, leaves, and fruit. The optimum temperature range where disease symptoms develop is between 80° and 86°F. The disease can become very severe during late spring to summer when temperatures and relative humidity in olive orchards are high.

Because cankers caused by the genus Botryosphaeria can colonize the vascular tissue very fast, it is critical to manage the disease properly.


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Olive News

Up-To-The-Minute Information Pertaining To The Olive Industry In Northern California.

Friday, October 11, 2019, 8:00 a.m. - 9:30 a.m.

Join your local team of UC Cooperative Extension Farm & IPM Advisors to discuss current pest management and production issues in orchard crops.

Space is limited - please RSVP to Emily Symmes at (530) 538-7201 or [email protected] by October 10th to let us know if you plan to attend.

Sacramento Valley Olive Day

June 18 th , 2019, 9:00 am to noon

131 E. Walker Street Building #4, Orland, CA
(Same plaza as Papa Murphy’s)

9:00am – Laws and Regulations Update
Glenn County Agricultural Commissioner’s Office

9:30am – Updates on Registration Status of New Pesticides for Olives
Dr. Dani Lightle, UCCE Orchards Advisor, Glenn, Butte & Tehama Counties

10:00am – Sustainable Groundwater Management: A Local Update
Lisa Hunter, Water Resource Coordinator, Glenn County Department of Agriculture

10:45am – Olive Oil Commission of California – Commission Update
Marilyn Dolan, Outreach Committee, OOCC

11:15am – Xylella fastidiosa Internationally and Potential Risks to California Olive Industries
Dr. Rodrigo Krugner, Research Entomologist, USDA ARS

1.5 hours of DPR CE Credits (0.5 Laws, 1 Other) requested.

In this issue:

Sacramento Valley Olive Day

July 6 th , 2018, 8:00am to noon

131 E. Walker Street Building #4, Orland, CA
(Same plaza as Papa Murphy’s)

8:30am – Laws and Regulations Update
Samantha Skelly, Glenn County Agricultural Commissioner’s Office

9:00am – Weed Control in Olives
Dr. Mariano Galla, UCCE Weed Science Advisor, Glenn, Butte & Tehama Counties

9:30am – Emerging Olive Diseases and Neofabraea Control Options
Dr. Florent Trouillas, UCCE Plant Pathology Specialist, Kearney Agricultural Research & Extension Center

10:00am – Thoughts on 2018 Bloom: Freeze Damage or Alternate Bearing?
Bill Krueger, UCCE Orchards Advisor Emeritus, Glenn County

10:45am – Current Status of Olive Trade Issues
Dr. Dan Sumner, Director, UC Agricultural Issues Center

11:15am – Olive Knot Research Update
Dr. Jim Adaskaveg, Plant Pathologist, UC Riverside

Mechanical Harvest Field Day

October 8, 9:00 to 11:00

Location: Intersection of MM and 6th, Capay

Interested in seeing the olive trunk shakers in action? Want more information on pruning trees to achieve the greatest harvest efficiency? Swing by between 9 and 11 on October 8, to enjoy some coffee, see the trunk shakers and have your questions answered. Gavin Nielsen with NielsenTechnologies will be on hand to talk about how the mechanical harvester has evolved over the years and how to adapt your orchard for machine harvest.

Togettothemeeting,drive toMMand6th,thenfollowthesandwichboardsigns to thefield location.

  • Olive Quick Decline in Italy is associated with unique strain of Xylella fastidiosa

  • What Values Should Olive Growers Use for Estimating Crop N Removal at Harvest?

  • UC Davis Olive Center: Sensory Evaluation of Olive Oil Certificate Courses

Olive "Quick Decline" in Italy Associated with Pathogen Common in California

Pre-emergence Herbicides for Olive Orchard Weed Control

Additional Resources From the UC Davis Olive Center

Is it the Right Small Business Accounting Software for Your Operation? Join us for an Introductory Interactive Overview of QuickBooks ® Use for Agricultural Enterprises with Plenty of Time for Questions and Answers

Sacramento Valley Olive Day - May 1, 2013

Thank you to Bell Carter Olives, California Olive Ranch, Musco Family Olives, and West Coast Olives for their sponsorship of this event.

Please phone 865-1105 to make your lunch reservation or email [email protected]

1620 Solano Street, Corning

Canopy Shaker Demonstration

Sacramento Valley Olive Day - Wednesday, April 18, 2012

Olive Pest Management Workshops

. Olive Fly Trapping Results for Glenn and Tehama Counties for 2010

Olive Mechanical Harvest Demonstration Meeting

What Can I Do To Size My Fruit - The Million Dollar Question?


Watch the video: Put 3 Drops Of Oil At A Magical Spot - The Belly Button!