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.
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 25-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 Kevin Price at kpprice@ksu.edu 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, service climatologist:
Figure 1. The Vegetation Condition Report for Kansas for January 14 – 27 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that snow was limited to the western third of the state. Unfortunately, moisture from the events was minimal. The Northwest Division averaged only 0.01 inches of moisture during the period. The West Central and Southwest Divisions average 0.04 inches. The only other division averaging more than zero was the South Central.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for January 14 – 27 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that lower NDVI values are most prominent in the Central, South Central and Southeastern Divisions. These areas had milder conditions last winter that favored more plant development.
Figure 3. Compared to the 25-year average at this time for Kansas, this year’s Vegetation Condition Report for January 14 – 27 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that most of the state has close to average biomass activity. Slightly above-average NDVI values can be seen in extreme the extreme northeast (Doniphan County) and the extreme southwest (Morton and Stevens counties).
Figure 4. The Vegetation Condition Report for the Corn Belt for January 14 – 27 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that a large portion of western South Dakota, eastern Nebraska, Kansas and western Missouri missed the snow. Drought conditions in southeast Kansas were downgraded to abnormally dry, as this portion of the state typically sees more winter moisture than the rest of the state.
Figure 5. The comparison to last year in the Corn Belt for the period January 14 – 27 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that NDVI values are higher in the western areas of the region and lower in the eastern portions. Persistent cold and snow cover have contributed to that difference. Note there is again a splice line in western Ohio, due to the persistent cloud cover in the area. Biomass production is most likely lower than depicted, in keeping with the rest of the region.
Figure 6. Compared to the 25-year average at this time for the Corn Belt, this year’s Vegetation Condition Report for January 14 – 27 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that greatest area of above-average NDVI readings is in the western and central portions of the region. Lack of snow cover is influencing this pattern. Eastern Nebraska and western Iowa continue to have lower-than-average snow coverage. The above-average NDVI values in western Ohio are the result of a splicing issue. Conditions are likely to be similar to the rest of the state and to Indiana. In these areas, snow coverage has been greater than usual.
Figure 7. The Vegetation Condition Report for the U.S. for January 14 – 27 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that snow cover skipped the Central Plains, but did occur in east Texas through Louisiana. The recent winter storm event from Alabama through the Carolinas will show on next week’s images.
Figure 8. The U.S. comparison to last year at this time for the period January 14 – 27 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that NDVI values are higher in the Northwest and lower in the Midwest. The major difference is the amount of snow cover compared to last year. For example, the Intermountain West has an average coverage of 41% and an average depth of 2.1 inches this year. Last year, the average coverage was 82% and the average depth was 10.4 inches. In the Allegheny front area of the Midwest, last year had an average coverage of just 27% and an average depth of just 0.6 inches. This year the coverage is 96% and the average depth is 4.1 inches.
Figure 9. The U.S. comparison to the 25-year average for the period January 14 – 27 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that snow cover has greatly influenced the NDVI values. Particularly noteworthy are the below-average values in central California, where continued drought is impacting vegetative activity. Also, the above-average NDVI values in these areas is not promising, as that indicates lower snowfall and thus lower moisture reserves, coupled with higher demand. The above-average NDVI values in western Ohio and eastern Pennsylvania are artifacts of the splicing procedure and not actually increased biomass activity.
Mary Knapp, Agronomy, Weather Data Library mknapp@ksu.edu
Kevin Price, Agronomy and Geography, Remote Sensing, Natural Resources, GIS kpprice@ksu.edu
Nan An, Graduate Research Assistant, Ecology & Agriculture Spatial Analysis Laboratory (EASAL) nanan@ksu.edu