Reap Benefits With Citrus Mechanical Harvesting

A Healthy Harvest

To be competitive in an increasingly global marketplace, Florida citrus growers must reduce harvesting costs. Furthermore, immigration issues may force a substantial decrease in the available numbers of workers to harvest citrus. These concerns pushed the Florida Department of Citrus (FDOC) to re-examine the feasibility of mechanical harvesting for citrus. For the last few years, the FDOC and the University of Florida/Institute of Food and Agricultural Sciences (UF/IFAS) have been supporting harvesting research and evaluating several mechanical harvesting machines and abscission chemicals to increase the efficiency of mechanical harvesting.

Research Disproves Reservations

Despite the substantial cost savings of mechanical harvesting relative to conventional hand harvesting, the adoption of mechanical harvesting has been slower than expected. Many factors contribute to the slow acceptance of mechanical harvesting. One factor is the visible damage to the trees that can include breaking of branches, sloughing of trunk bark, exposing root systems, and noticeable leaf, flower, and young fruit drop. Growers worry that these visible signs of physical damage will have negative effects on tree health and future yields. When healthy, well-managed trees are mechanically harvested, there is no scientific evidence that these injuries negatively reduce tree yields or longevity.

For the last five years, several studies have focused on the physiological effects of mechanical harvesting. Short- and long-term physiological measurements revealed that the water use, growth, and yield of healthy, well-managed and well-prepared citrus trees was not negatively affected by mechanical harvesting — even when mechanically harvested annually for several consecutive years. The removal of healthy leaves by mechanical harvesting has no long-term effect on trees, and in some cases, can even be beneficial to light penetration, growth, and yield. Any visible root damage after shaking does not measurably affect water and nutrient uptake by the root system. In addition, root growth and recovery, return bloom, and water status were similar to that of hand-harvested trees.

Why Move To Mechanical?

The objectives of mechanical harvesting are:

1) To decrease harvesting costs, which implies an increase in  “on-tree” revenues.

2) To increase overall labor productivity, which implies a reduction in the required number of harvest workers.

Many tree and vegetable crops have moved to mechanical harvesting to survive. There is now a general consensus among industry leaders that mechanical harvesting offers the greatest potential to reduce costs and keep the citrus juice industry economically viable. It has been well documented that the major benefit of mechanical harvesting relies on its efficiency and lower costs in comparison with hand harvesting.

Mechanical harvesting during peak bloom in Valencia removes some flowers, but does not diminish fruit set. These trees did not develop any physiological stress as measured by stem water potential or leaf photosynthesis. So long as the diameter of the young green Valencia fruit is less than about 1 inch, mechanical harvesting of Valencias does not reduce yields the following year. Once the young fruitlets exceed this size, however, aggressive trunk or canopy shaking will likely depress the following year’s yield by at least 25%.

The Bottom Line

Except for late-season Valencia with large young fruit, all research studies where citrus trees have been harvested mechanically for many years have shown no reductions in yield or tree health. Currently, work is underway to develop an abscission chemical which could solve the late-season Valencia problem.

Leave a Reply

Featured Stories
Biocontrols 2015 Conference
CitrusGrowers Go In-Depth At Biocontrols 2015 Conference & Tradeshow
March 9, 2015
The first-of-its-kind event brought growers, researchers, regulators, and suppliers together for a two-day discussion on the latest biocontrols tools and technologies. Read More
Crop ProtectionAt Paramount Farming, Mating Disruption Pays Off
February 10, 2015
To say Brad Higbee is an expert in mating disruption, the use of pheromones to confuse target pests and reduce Read More
Crop ProtectionGrower Experienced In Biocontrols Says: Be Patient
February 4, 2015
The use of biocontrols in all aspects of agriculture is becoming more widespread. But incorporating biocontrols in a vegetable farming Read More
FruitsSounding Off On GMOs: The Arctic Apple Decision
March 27, 2015
Industry leaders share their feelings on the recently approved genetically modified apples. Read More
BerriesBuilding A Better Black Raspberry
March 27, 2015
Studies focusing on consumer preference, aphid resistance, heat tolerance, and genetics aim to capitalize on an expanding market. Read More
CitrusMore California Citrus Placed Under Psyllid Quarantine
March 27, 2015
Asian citrus psyllid is found in Madera County – the heart of the San Joaquin Valley. Read More
FruitsAhead Of The Curve, Part 2
March 27, 2015
Get educated with great resources in the tree fruit industry available at your fingertips. Read More
Apples & PearsMeet USApple’s Class of 2015 Young Apple Leaders
March 27, 2015
Young decision-makers see trip as an opportunity make sure the voice of the apple industry is heard by representatives. Read More
GrapesGlassy-Winged Sharpshooter Found In Marin County
March 26, 2015
This pest, known to spread Pierce’s Disease, could devastate California winegrapes. Read More
GrapesFirst Raisin Grape That Dries Naturally On Vine Developed
March 26, 2015
The new Sunpreme variety eliminates the need for growers to cut into woody canes before harvest. Read More
Fresh From Florida Strawberry Parfait recipe
BerriesNew Partnership Sends Florida Strawberries To Puerto Rico
March 26, 2015
Latest addition extends Sunshine State’s agricultural export reach in the Caribbean. Read More
drought management; irrigation; water management
FruitsHow To Become A Soil Sleuth
March 26, 2015
To correctly apply the proper nutrients at the right rates, you need to know where your fields are deficient and how to correctly diagnose a disorder. Read More
NutsWhy You Should Use Low-Rate Applications Of Potassium
March 26, 2015
These rates provide growers a low-cost method comparable to conventional applications. Read More
The Latest
FruitsSounding Off On GMOs: The Arctic Apple Decision
March 27, 2015
Industry leaders share their feelings on the recently approved genetically modified apples. Read More
BerriesBuilding A Better Black Raspberry
March 27, 2015
Studies focusing on consumer preference, aphid resistance, heat tolerance, and genetics aim to capitalize on an expanding market. Read More
CitrusMore California Citrus Placed Under Psyllid Quarantine
March 27, 2015
Asian citrus psyllid is found in Madera County – the heart of the San Joaquin Valley. Read More
FruitsAhead Of The Curve, Part 2
March 27, 2015
Get educated with great resources in the tree fruit industry available at your fingertips. Read More
Apples & PearsMeet USApple’s Class of 2015 Young Apple Leaders
March 27, 2015
Young decision-makers see trip as an opportunity make sure the voice of the apple industry is heard by representatives. Read More
GrapesGlassy-Winged Sharpshooter Found In Marin County
March 26, 2015
This pest, known to spread Pierce’s Disease, could devastate California winegrapes. Read More
GrapesFirst Raisin Grape That Dries Naturally On Vine Develop…
March 26, 2015
The new Sunpreme variety eliminates the need for growers to cut into woody canes before harvest. Read More
Fresh From Florida Strawberry Parfait recipe
BerriesNew Partnership Sends Florida Strawberries To Puerto Ri…
March 26, 2015
Latest addition extends Sunshine State’s agricultural export reach in the Caribbean. Read More
drought management; irrigation; water management
FruitsHow To Become A Soil Sleuth
March 26, 2015
To correctly apply the proper nutrients at the right rates, you need to know where your fields are deficient and how to correctly diagnose a disorder. Read More
NutsWhy You Should Use Low-Rate Applications Of Potassium
March 26, 2015
These rates provide growers a low-cost method comparable to conventional applications. Read More
Cold ProtectionWind Machine, Electric Pruners Donated To MSU Research …
March 25, 2015
New equipment to help protect research blocks from frost damage and provide center with latest technology. Read More
CitrusProposed Farm Bill Provision To Limit Payments To Non-F…
March 25, 2015
USDA has proposed a new rule which would limit payment to those who are only actively engaged in farming. Read More
Pennsylvania hard cider guild logo
Apples & PearsPennsylvania Hard Cider Producers Founded Independent T…
March 25, 2015
The Pennsylvania Cider Guild is designed to help promote and educate members and consumers. Read More
FruitsHow To Get Started With Partnerships And Sponsorships
March 25, 2015
Mark Saunders of Saunders Farm says your business is never too small or too big to get more value for what you do on your farm. Read More
FruitsValue Through Partnerships And Sponsorships [Opinion]
March 25, 2015
Mark Saunders of Saunders Farms says admission is one way to get value for what you do, but sponsorships and partnerships are the next level. Read More
chateau hough urban vineyard Cleveland Ohio
GrapesFrom Riots To Vineyard — A Story of Urban Revival
March 25, 2015
Ex-convict’s inner-city vineyard in the Hough neighborhood in Cleveland an opportunity for those leaving incarceration for a bright future in viticulture. Read More
FruitsWorld Ag Expo 2015: New Tools For Fruit Growers
March 24, 2015
From wind machines to solar-powered pumps, here is some of the new equipment on display this year's edition of the nation's largest farm show. Read More
Apples & PearsNeedles Found In Honeycrisp Sold At Grocery Store
March 24, 2015
Apples were believed to be tampered with; initial surveillance footage was inconclusive. Read More