http://www.theledger.com/article/20090825/NEWS/908255026?Title=Citrus-Harvesters-Need-Boost

Citrus Harvesters Need Boost
Use of mechanical harvesting for citrus has stalled at 7 percent of Florida grove land.

By Kevin Bouffard

Published: Tuesday, August 25, 2009 at 5:48 p.m.
Last Modified: Tuesday, August 25, 2009 at 5:48 p.m.

HAINES CITY | Use of mechanical harvesters by Florida citrus growers has stalled in recent seasons, but supporters hope a new chemical boosting efficiency will lead to more widespread adoption.

"The amount of fruit removal is not as high as growers want to get," Bob Ebel, associate professor of citrus physiology at the Southwest Florida Research and Education Center in Immokalee, told The Ledger on Tuesday.

Research with canopy shakers shows the machines remove only 75 to 85 percent of the oranges on a tree, he said.

As a result, growers have used mechanical harvesters on just about 35,000 acres, about 7 percent of Florida's citrus grove acreage, for the past several seasons, Ebel told a couple hundred growers last week at the Citrus Expo in Fort Myers.

A canopy shaker features a column of several rotating wheels, each with long tines that penetrate the tree branches and shake the fruit loose.

To boost efficiency, researchers are experimenting with an abscission chemical known as CMNP. The chemical loosens the bond between the tree stem and the fruit, allowing the latter to separate more easily.

Experiments show using CMNP with canopy shakers boosted the harvesting rate to more than 90 percent on early-season Hamlin oranges and to more than 95 percent on late-season Valencia oranges, Ebel said.

Using CMNP on Valencias is particularly important because it can extend the use of the harvesting machines into May, he said.

Currently growers don't use mechanical harvesters on Valencia trees after May 1. By that time, the tree also has immature fruit that will become the next season's crop, and using the harvesters will remove both mature and immature fruit.

But research shows CMNP breaks the bond on mature fruit without affecting the immature Valencias, Ebel said. That allows the harvester to loosen only mature oranges.

"In my mind, there's no question we can go deeper into May" with machines plus CMNP, he said.

However, the jury is still out regarding whether mechanical harvesting with CMNP can be used in June, the final month of the Florida citrus harvest, without affecting the immature Valencias, Ebel acknowledged. The question requires future research.

The research also show using CMNP reduces the force the canopy shaker must employ on the tree, he said.

The tree damage issue also has limited the use of the harvesting machines as many growers continue to express concern the machines break branches, lowering future fruit production.

Ebel and other researchers hope more widespread use of CMNP will help address those issues. The U.S. Environmental Protection Agency, which is reviewing a licensing application for the chemical, currently restricts its use to just 10 acres.

By Sept. 30, researchers expect to ask the EPA for a permit to allow for CMNP use on 25,000 acres, Ebel said. It will probably take 18 months to get that permit.

If expanded CMNP use proves safe and effective, the industry could apply for unconditional use, which could lead to widespread adoption of the harvesters next decade, he said.

[ Kevin Bouffard can be reached at kevin.bouffard@theledger.com or at 863-422-6800. ]

............"Environmental Protection Agency ...currently restricts its use to just 10 acres. By Sept. 30, researchers expect to ask the EPA for a permit to allow for CMNP use on 25,000 acres, ...It will probably take 18 months (OF COURSE) to get that permit."...........

With the EPA sticking their nose into the mechanical harvesting issue, it will probably take much longer than 18 months, and ALSO many millions of unneeded additional dollars in cost to the citrus industry. We can only hope that when the EPA is in the grove checking on mechanical harvesting, they will not find some of that highly "toxic" environmentally destructive gas CO2 "raising" the temperature of the groves air to unsafe worker levels. - Millet (1,234-)

The question is do we want to eat 5-chloro-3-methyl-4-nitro-1H-pyrazole ?

Eat ?? We?? The question really is, would the needs of the citrus growers be better served, and more effectively served, with studies done by organizations such a University of Florida, IFAS, or private industry, instead of a bloated governmental agency with a very long record of issuing debilitating fines, unneeded delays, exorbitant demands, and a long history of money wasted? I'm sure EPA is certainly not close to any type of authority, nor has any type of real expertise, concerning citrus. Since when has a government employee based organization, ever been equal to what private enterprise has accomplished for the betterment of the American people, and industry, of this country? - Never. The EPA knows as much about citrus, as the government knows about government controlled "health care". I don't want to carry this on and on, so this will be my last statement on this issue. Take care. - Millet (1,333-)

Wow, excellent argument. Very well put. The best explanatation I have heard....ever . I agree completely. Tom

Maybe you are not old enough to remember life before EPA. Where I grew up industries put anything they wanted in the river. I worked on the Mobile River--the river and the banks were covered with a black oily sludge--nothing lived there. Here in Pensacola, they measured the fish kills in square miles of solid dead fish. Maybe you trust industry to be a good citizen, but the evidence points to the contrary.