Comparative Vegetation Condition Report: March 14 - 20
The weekly Vegetation Condition Report maps below 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 27-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.
The Vegetation Condition Report (VCR) maps were originally developed by Dr. Kevin Price, K-State professor emeritus of agronomy and geography, and his pioneering work in this area is gratefully acknowledged.
The maps have recently been revised, using newer technology and enhanced sources of data. Dr. Nan An, Imaging Scientist, collaborated with Dr. Antonio Ray Asebedo, assistant professor and lab director of the Precision Agriculture Lab in the Department of Agronomy at Kansas State University, on the new VCR development. Multiple improvements have been made, such as new image processing algorithms with new remotely sensed data from EROS Data Center.
These improvements increase sensitivity for capturing more variability in plant biomass and photosynthetic capacity. However, the same format as the previous versions of the VCR maps was retained, thus allowing the transition to be as seamless as possible for the end user. For this spring, it was decided not to incorporate the snow cover data, which had been used in past years. However, this feature will be added back at a later date. In addition, production of the Corn Belt maps has been stopped, as the continental U.S. maps will provide the same data for these areas. Dr. Asebedo and Dr. An will continue development and improvement of the VCRs and other advanced maps.
The maps in this issue of the newsletter show the current state of photosynthetic activity in Kansas, and the continental U.S., with comments from Mary Knapp, assistant state climatologist:
Figure 1. The Vegetation Condition Report for Kansas for March 14 – March 20, 2017 from K-State’s Precision Agriculture Laboratory shows the light snow that fell during the period. Amounts were generally less than an inch and melted quickly. The little vegetative production is mainly in south central Kansas, although it continues to expand northward. This is not unexpected even with the warmer-than-normal temperatures.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for March 14 – March 20, 2017 from K-State’s Precision Agriculture Laboratory shows much lower NDVI values across much of Kansas. The winter wheat is less advanced this year than last, particularly in western Kansas, where dry fall conditions hampered establishment. In northeast Kansas, persistent cloud cover also accounted for reduced NDVI values.
Figure 3. Compared to the 27-year average at this time for Kansas, this year’s Vegetation Condition Report for March 14 – March 20, 2017 from K-State’s Precision Agriculture Laboratory much of the state has expanding areas of below-average photosynthetic activity. The highest NDVI values are in the central and south central parts of the state, where precipitation has been more favorable. The low NDVI values in northeast Kansas are largely due to persistent cloud cover.
Figure 4. The Vegetation Condition Report for the U.S for March 14 – March 20, 2017 from K-State’s Precision Agriculture Laboratory shows the highest NDVI values are confined to the South, particularly in east Texas and Louisiana. Snow coverage was mostly in the Upper Midwest and New England. Parts of Upstate New York had relief from the snow deficit that has been present for most of the winter.
Figure 5. The U.S. comparison to last year at this time for March 14 – March 17, 2017 from K-State’s Precision Agriculture Laboratory shows the impact that the split in snow cover has caused. Much lower NDVI values prevail from the Pacific Northwest through the northern Plains and into New England, where snow coverage continues to be much higher this year. In contrast, the Central Plains has had less moisture. Winter wheat conditions are much poorer than last year at this time.
Figure 6. The U.S. comparison to the 27-year average for the period of March 14 – March 20, 2017 from K-State’s Precision Agriculture Laboratory shows an area of below-average photosynthetic activity in the Intermountain West, where snow cover is greatest. Above-average NDVI values are visible in the Midwest from Iowa through Pennsylvania and northward. This is particularly true in central Minnesota and Wisconsin. Warmer-than-normal temperatures and little snow cover has favored early vegetative growth with continued risk of freeze damage.
Mary Knapp, Weather Data Library
Ray Asebedo, Precision Agriculture
Nan An, Imaging Scientist