DEC, 2007       

VOL. 21, NO. 12                                                                             





Aside from the misery of the frequent drizzle, the coolness of the last couple of weeks has been nice. And the cooler weather seems to increase natural color development in the field.

Rainwise, however, the holiday fronts didn’t amount to much, as I haven’t seen more than half an inch total anywhere. For the most part, the chilly drizzle was just kind of miserable, but didn’t slow things down much at all.


The USDA has finally implemented the new canker rules for Florida citrus—over the protests of other citrus-producing states. Actually, I think the only surprise was that it took so long.

Pre-harvest orchard inspections for freedom from citrus canker are no longer necessary for the fresh shipment of Florida citrus out of state.  Instead, the USDA has ramped up the number of inspectors and put them into packinghouses where they are supposed to inspect each lot of fruit to assure freedom from canker before the fruit is packed. Any lot found to have canker must either be sold within Florida or sent to the juice plant.

While some packers aren’t happy to have canker inspectors underfoot all day,

most seem to see it as a necessity that will benefit growers who won’t be having entire groves  knocked out of fresh channels because of finding canker in one or two trees in the block.


Florida citrus still cannot be shipped to California, Texas or other citrus-producing states, but you can bet the farm that the Florida folks are working hard to overturn this aspect of the rule. You can also bet that California and Texas will move mountains to prevent Florida fruit from entering our borders.

A complicating factor is that there are large, multi-state distribution centers in states adjacent to citrus-producing states.  Those centers can now receive the inspected, “canker-free” fruit from Florida. If you believe that those distribution centers won’t forward Florida citrus into a citrus-producing state, I have “some oceanfront property” that you might like to buy.

If the inspectors could possibly intercept each and every single piece of infected fruit in a packinghouse, the risk might be negligible. Problem is, citrus canker, citrus blackfly, Asian citrus leafminer, Asian citrus psyllid and Asian citrus greening all were illegally imported into Florida in the last decade or so, in spite of all the best efforts of inspectors whose job it was to prevent their entry. And it’s not just Florida—look at all of the exotic fruit fly finds in California in recent years.

Here in Texas, we already have two of the five import pests that plague Florida —leafminer and psyllid—and we are vigorously and constantly checking for the other three. Yes, there are millions of passengers coming through ports of entry every day, so inspectors are going to miss something occasionally.  But there are tens of millions of oranges and grapefruits going down the packing lines, so what are the odds of missing a few?

Florida Citrus Mutual’s Executive VP and CEO, Mike Sparks, indicated that Mutual would continue to try to persuade federal officials to allow Florida to ship to other citrus-producing states. If that should come to pass, can the affected states override the feds and impose a state-level quarantine?


Because of the September start of shipping this season, fruit movement has been running pretty good, with weekly volumes topping the comparable weeks last year—until the week ending November 17. That week’s volume was about 90 thousand cartons below last season.  In addition, last week’s (Week 8) volume was over 200 thousand below the previous week (Week 7) this season.

It’s hard to pin down a cause for the decline. Orange shipments were at about three-fourths the prior week, while grapefruit was the major loser at only about 40 percent of the prior week’s volume. It was the week leading up to Thanksgiving, and there were no complicating weather factors, so one would have expected a much higher volume.

Still, the industry was still up by about 50 percent over last season at the same time.  The subsequent week was already shortened by the Thanksgiving holiday and the couple of days of drizzle, so Week 9 might be expected to have had lighter volume.  Because I hope to get this newsletter out before the weekend, I can’t verify this guess until sometime next week, as it takes time for TVCC to obtain, verify and total all the numbers.


Some of us tend to associate a full moon in winter with colder weather.  Indeed, last week’s cold spell coincided with a full moon on November 24. The next full moon is on Christmas Eve.

Of the two great freezes in the 80s, the 1983 freeze hit south Texas a couple of days after the full moon.  However, the 1989 freeze hit us a few days before the new moon. Since the full moon association wasn’t there for both of those freezes, I wondered if the perigee of the moon might coincide. Perigee is when the moon is closest to the earth; apogee is when it is farthest.

In December 1983 when the moon was full on the 20th, the perigee occurred on December 22 when the moon was only 364,856 km away. By contrast, the infamous Christmas 1989 freeze occurred when the moon was waning to new and was at its apogee on December 22—405,216 km away.

So, neither the full moon nor its closeness to the earth correlate with the severe freezes of the 80s.  Still, it always “feels” colder on a full moon night in winter…

While checking out the times of these various events in Wikipedia and a couple of other sites, I ran across a word that I did not know—analemma, so I clicked it up.  If you ever wondered about the elongated “Figure 8” on a globe, this is the reason.  Because of the earth’s wobble in its orbit around the sun, the sun appears to be in a slightly different spot in the sky when viewed at the same time of day over a year.

On this site (, a fellow in Greece took 35 to 45 multiple exposures (one piece of film) of the sun from the same spot at the same time every week (obviously, clouds occasionally prevented seeing the sun).  He claims several “firsts” in this effort, but there are several images depicting the Figure 8.

I know…this ain’t citrus, but I have been fascinated with such things ever since I made a sundial many years ago.


The USDA APHIS instituted a quarantine on the 32 Texas counties in which Texas A&M University scientists have found Asian citrus psyllids.  The APHIS quarantine was announced November 2, and the state of Texas had until December 1 to institute a parallel quarantine.  On November 30, Texas Department of Agriculture instituted the quarantine. Had TDA not done so, the entire state would have been quarantined by APHIS.

Basically, pysllids have been confirmed in all counties more or less below a line scribed from Houston to Victoria, San Antonio, Uvalde and Eagle Pass.  No citrus nursery plants may be moved from this area without having been treated chemically to preclude the presence of psyllid.

The idea is to keep psyllid from spreading to areas where it does not already exist—in particular into East Texas, which officials hope will serve as a buffer area to preclude the introduction of citrus greening into Texas.  Because greening is transmitted by the psyllid and because greening kills the trees, there is good cause for the quarantine.

For the record, Dr. John daGraca at the Citrus Center informs me that of the 100s of citrus trees tested for greening, the disease has not been detected in Texas.  For the most part, surveys for greening are being carried out in the Valley, Corpus and Houston.

Under the terms of the quarantine, any nursery within the quarantine area can ship citrus trees and/or budwood to “free” Texas only after first entering into a compliance agreement with TDA and then after appropriate chemical treatment.  Chemical treatment includes a drench with imidacloprid (Admire) within 30 days of shipment plus a foliar spray within 10 days of shipment with either acetamiprid (Assail), chlorpyrifos (Lorsban) or fenpropathrin (Danitol).

If you ship out of state (some states are off-limits), you must still comply with the requirements to ship into “free” Texas.  Makes sense, as any land route out of the quarantined part of the state passes through “free” Texas.


Professor & Extension Horticulturist
2401 East Highway 83
Weslaco TX 78596


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