Authors: Mary Knapp, Kevin Price, Nan An
K-State’s Ecology and Agriculture Spatial Analysis Laboratory (EASAL) produces weekly Vegetation Condition Report maps. These maps can be a valuable tool for making crop selection and marketing decisions.
Two short videos of Dr. Kevin Price explaining the development of these maps can be viewed on YouTube at:
The objective of these reports is to provide users with a means of assessing the relative condition of crops and grassland. The maps can be used to assess current plant growth rates, as well as comparisons to the previous year and relative to the 26-year average. The report is used by individual farmers and ranchers, the commodities market, and political leaders for assessing factors such as production potential and drought impact across their state.
NOTE TO READERS: The maps below represent a subset of the maps available from the EASAL group. If you’d like digital copies of the entire map series please contact Nan An at firstname.lastname@example.org and we can place you on our email list to receive the entire dataset each week as they are produced. The maps are normally first available on Wednesday of each week, unless there is a delay in the posting of the data by EROS Data Center where we obtain the raw data used to make the maps. These maps are provided for free as a service of the Department of Agronomy and K-State Research and Extension.
The maps in this issue of the newsletter show the current state of photosynthetic activity in Kansas, the Corn Belt, and the continental U.S., with comments from Mary Knapp, assistant state climatologist:
Figure 1. The Vegetation Condition Report for Kansas for April 28 – May 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that the highest level of photosynthetic activity continues in the central to southeastern quarter of the state. Patches of moderate photosynthetic activity are visible in northwest Kansas, and in southwest Kansas along the Arkansas River basin.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for April 28 – May 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows most of the state with much higher NDVI values than last year. At this time last year, statewide moisture was only 40 percent of normal for the year-to-date. This year, the statewide average is 78 percent of normal. Northeast Kansas is the exception. Last year, it was slightly above normal for the year-to-date, while this year it is averaging only 76 percent of normal.
Figure 3. Compared to the 26-year average at this time for Kansas, this year’s Vegetation Condition Report for April 28 – May 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that the greatest departure from average is in north central and northeast Kansas. Drought and winterkill are major factors.
Figure 4. The Vegetation Condition Report for the Corn Belt for April 28 – May 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that highest NDVI values are in southern Missouri into Kentucky. Mild temperatures and favorable moisture have favored growth in that area. The exception is in the Boot Heel of Missouri, where excess moisture has been a problem.
Figure 5. The comparison to last year in the Corn Belt for the period April 28 – May 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows higher NDVI values across much of Kansas and Missouri. Higher precipitation amounts have favored plant development in these areas. Central South Dakota has lower photosynthetic activity this year, as moisture levels have been less favorable. The impact from the most recent rains have yet to be seen.
Figure 6. Compared to the 26-year average at this time for the Corn Belt, this year’s Vegetation Condition Report for April 28 – May 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows above-average photosynthetic activity is concentrated in the southwestern portion of the region. South Dakota has the largest area of below-average photosynthetic activity. Recent moisture in the area has not yet been reflected in increased biomass production.
Figure 7. The Vegetation Condition Report for the U.S. for April 28 – May 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that biomass production is highest in the southern U.S. The exception is along the Mississippi River Valley. High water levels there have reduced plant production.
Figure 8. The U.S. comparison to last year at this time for the period April 28 – May 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows the Central and Southern Plains have much higher photosynthetic activity. Precipitation patterns have been much more favorable this year. There is also an area of greater NDVI values along the Pacific Northwest. This is likely to decrease in coming months as summer temperatures stress drought areas.
Figure 9. The U.S. comparison to the 26-year average for the period April 28 – May 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows the Southern Plains with much above-average photosynthetic activity. Kansas is the transition state, with below-average biomass production in the northern areas of the state. The most intense area of below-average values is in South Dakota. The recent rains in these areas have yet to have an impact on NDVI values. Lack of snow in the west continues to be evident with the above-average NDVI values along the Sierras.
Mary Knapp, Weather Data Library
Kevin Price, Professor Emeritus, Agronomy and Geography, Remote Sensing, GIS
Nan An, Graduate Research Assistant, Ecology & Agriculture Spatial Analysis Laboratory (EASAL)