Presentation on theme: "AG OUTLOOK LA NIÑA WINTER 2010 Clyde Fraisse Agricultural and Biological Engineering University of Florida November 18, 2010 Albany, GA."— Presentation transcript:
AG OUTLOOK LA NIÑA WINTER 2010 Clyde Fraisse Agricultural and Biological Engineering University of Florida November 18, 2010 Albany, GA
Potential Impacts on Agriculture La Niña 2010-2011 Winter vegetables Winter pasture Temperate fruits Forestry Row crops
Major Freezes in Florida Citrus Freeze EventENSO Phase December 1894Neutral February 1899Neutral December 1934Neutral January 1940Neutral December 1962Neutral January 1977El Niño January 1981Neutral January 1982Neutral December 1983Neutral January 1985Neutral December 1989Neutral January 1997Neutral Adapted from: John Attaway, “A History of Florida Citrus Freezes
Winter Vegetables Tomato and green peppers generally yield more during La Niña years than during Neutral or El Niño years. Dry weather associated with La Niña generally decreases fungal and bacterial diseases. Increased solar radiation is also a factor. Source: Hansen, J.W., Hodges, A.W., Jones, J.W., 1998. ENSO inﬂuences on agriculture in the southeastern US. J. Climate 11 (3), 404– 411.
Winter Pasture Success of winter pastures depends on rainfall. This is especially true when overseeding. In central and south peninsular Florida, overseeding of cool-season annuals into an established grass sod often fails due to insufficient soil moisture
Winter Pasture Based on the current dry conditions across parts of the Southeast and the probability of a dry winter, the following considerations should be made in regard to winter pasture: Soil moisture at planting will be an important factor for success, postpone planting If the soil is dry; Prioritize planting in prepared seedbeds where chances of success are higher, avoid overseeding; Plant in best fields that typically hold moisture in the winter; Don’t invest only in winter forage, save some dollars for feed purchase; Be prepared to reduce stocking rates and number of grazing days with the expected reduced rainfall.
Temperate Fruits Seasonal climate variability impacts deciduous fruit production mainly because of a decrease in the satisfaction of dormancy that occurs by the accumulation of chilling hours (temperature at or below 45°F)
Chill Accumulation Variability Chill hours variability in: Alachua Hendry Hernando Marion Pasco Polk Sumter Chill Hours (32°F ≤ T < 45°F) From Oct 1 st to Feb 28 th Entire period of records 1948-2007 Different ENSO phases: Neutral El Niño La Niña C. W. Fraisse, Agricultural & Biological Engineering
Chill Accumulation Averages Entire Period of Records C. W. Fraisse, Agricultural & Biological Engineering
El Niño - Southern Oscillation Marion County 1948-2007 El NiñoLa NiñaNeutralAll Years Average405284362354 Minimum222146110 Maximum598500593598
Temperate Fruits - Diseases The dry weather during La Niña years is usually not conducive to fungal diseases such as Anthracnose and Botrytis fruit rots. Regular applications of fungicides may not be needed as often to suppress these diseases.
Seasonal Forecast of Disease Pressure Plant City, Florida – 1892 to 2009 C. W. Fraisse, Agricultural & Biological Engineering
Forestry Managers could consider: Re-scheduling planting of drought vulnerable seedlings Reinforce existing control efforts of southern pine beetle Delay the harvest of pine straw to retain soil moisture La Niña also brings the potential for a very active wildfire season.
Row Crops Warmer and/or drier conditions may help certain pests and diseases: Warm, dry winter may increase flower thrips abundance Warm conditions may also help soybean rust over-winter on kudzu in South Georgia and throughout the Panhandle of Florida If conditions are dry during the spring it may be best to kill cover crops earlier in order to preserve more moisture in the soil
Drought Monitoring and Forecasting
Agricultural Reference Index for Drought NOAA-Sector Applications Research Program Survey & Prototype Workshops in FL & GA Refinement of the tool Release of final version on AgroClimate Training Workshops AgroClimate Cycle Objective: Develop a decision support system on AgroClimate specifically designed to help forage producers cope and adapt to drought conditions in the southeastern USA
Drought Workshops w/ Forage Producers Fanning Springs, FL October 14, 2010 Tifton, GA October 15, 2010