AUGUST, 2008       

VOL. 22, NO. 8                                                                             





About the time the weather seemed to return to its summer normalcy of continued hot and dry, a tropical storm popped up in the western Caribbean, moved across the tip of the Yucatan and entered the Gulf of Mexico.  Initial forecasts were for landfall directly at the mouth of the Rio Grande as a Category 1 hurricane during the wee hours of Thursday morning (July 24).  However, Dolly was moving so fast that landfall was moved up to early Wednesday morning.

Rarely do tropical cyclones behave entirely as predicted, and Dolly was no exception.  As the weather folks put it, Dolly arrived just offshore from the mouth of the river and “hesitated”—and what an understatement!  According to the data, she paralleled South Padre Island for a couple of hours, with forward movement dropping into the 6-8 mph range and winds building to Category II strength before crossing the Island near the Cameron and Willacy County line, from whence she more or less continued inland in a WNW direction.

The direction took Dolly just southwest of Port Mansfield and then just north of Raymondville, from whence she dipped back to the south to pass over Linn San Manuel before resuming the WNW track that took her to Laredo, into Mexico and then into New Mexico before her final remnants ultimately died away somewhere in NW Texas.

The dip to the south at Linn San Manuel was a bit offline, but I have triple-checked the coordinates of the center of the storm and can only suggest that a) the track is correct according to the coordinates or b) Google Earth’s coordinates have some inaccuracies. See the map below for positions over time from 8:00 am Wednesday through 4:00 am Thursday, July 23-24.

Dolly's Track 4.jpg 


The most damage to citrus occurred east of Edinburg from about San Carlos along Hwy 107 to Rio Hondo, then down through Bayview and Los Fresnos.  Groves in the area between Expressway 83 and Hwy 107 in eastern Hidalgo County and western Cameron County suffered moderate damage.  The area south and west of Edinburg (where the majority of our citrus is located) had the least citrus damage, inasmuch as the storm had weakened considerably by the time its winds got there.  That is to say that winds at the storm center dropped below hurricane strength around the time she got to Linn San Manuel. 

After a couple of us stuck our necks out late Friday to independently arrive at an estimate of about 20 percent loss to grapefruit, others have since come forward suggesting that 20 percent may be a bit high.  And it might be—but I don’t mind at all if my estimate was too high.  In all actuality, we’ll never know anyway.  

The possibility of significant tree damage appears unlikely.  Although some trees were reportedly blown over in the Rio Hondo area, excess water in most of the groves has soaked in or drained off.  I was taught that standing water for over three days was detrimental to citrus trees, but I learned early on in Texas citrus that sour orange rooted trees can tolerate standing water for a longer time than that.

Rainfall amounts are mostly Doppler radar estimates, as few foolish souls ventured outside to empty rain gauges during the storm.  I did so at home, where I captured 7.85 inches between noon Wednesday and sunup Thursday.  However, even that measure doesn’t tell the whole story, as the rain was blowing more or less between 45 degrees and horizontally for most of that time—which is not conducive to capturing all of the precipitation.

Aside from citrus, cotton, corn, grain and cane fields were affected by this disaster—and those are about the majority of crops that were in the field.  I  have heard that cotton in many places will be a total wipeout, as is unharvested grain.  Some late-planted grain in the Mid-Valley area had headed out and now has a decided easterly lean to it, but should be okay.  Uncut corn may be salvageable once fields are dry enough to enter.  Sugar cane also has an easterly tilt to it, but I think most of it should recover in time for harvest.

It is my understanding that in terms of citrus crop insurance, adjusters for the various insurers will automatically assess all of their covered acreages in Cameron and Willacy Counties.  For Hidalgo County growers, it may be necessary to contact the insurer about potential losses.

Other Rain—

One of the problems in trying to write parts of this newsletter early in the month is that something like Dolly comes along and renders the previous effort null and void.  So it is with a piece I did about the July 3-8 rains of 4-10 inches across the Valley, the effects on some crops and the status of the waters in the reservoirs.  Even so, in my own case, I can count a bit over 16 inches total rain for the month at both my home in Weslaco and my grove in western Cameron County.  

I have only been here about 30 years, and an oldtimer once told me that the means in Texas are made up of extremes.  So it was with July’s rains, as 16 inches is a bit extreme, comprising about two-thirds of the average for the whole year.

More Psyllids—

California growers are justifiably concerned about the fact that an awful lot of psyllids were discovered just a couple of miles into Mexico in Tijuana, Baja California, Mexico.  That’s across the border from San Diego, in case you didn’t know.  Fortunately, none of the insects tested positive for the Asian citrus greening bacterium.  State and federal officials have naturally stepped up the surveys in San Diego County, with no psyllids having been found to date.

In Texas, 33 counties are still under quarantine for psyllid, but an additional 52 counties did not have psyllids.  I generated the following map highlighting the counties where citrus was surveyed and where psyllid was found (based on information provided by Dr. John DaGraca of the Citrus Center).  Some of the adjacent counties probably have citrus, also, but the surveyors did not locate citrus trees in them.  Present survey efforts are primarily focused on Asian citrus greening and are concentrated in the major metropolitan areas and the Valley.




Closing Comment—

Dolly was so much worse than we expected, mainly because she moved so slowly that the winds just continued to buffet the Valley even as rainfall amounts continued to rise—as did the flood waters in many neighborhoods and rural areas of the Valley.  Most of us survived with little or no damage that cannot be repaired in short order, but let us not forget that literally hundreds and hundreds of people are still in shelters or are trying to cope with flooded homes and cars.

The RGV Food Bank, the Salvation Army and countless other organizations are in desperate need of food, water and funds to continue to help those folks.  If you can, do your part, too. 

A special thanks goes to all the local community leaders, “First Responders”, Department of Public Safety, County and municipal law enforcement personnel, the Texas National Guard, the Department of Transportation, all the folks with the various utility companies (who arrived from almost everywhere), the media and everybody else who have helped and are helping the Valley to get through this disaster and to return to some semblance of normalcy.  Obviously, there are dozens of agencies, departments, companies and thousands of just plain folks who have also pitched in to help. 


Professor & Extension Horticulturist
2401 East Highway 83
Weslaco TX 78596


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