Comparative Vegetation Condition Report: February 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 February 7 – February 13, 2017 from K-State’s Precision Agriculture Laboratory shows a slight increase in photosynthetic activity. The areas of highest NDVI values are mainly in central and south central Kansas. This is not unexpected given the season.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for February 7 - February 14, 2017 from K-State’s Precision Agriculture Laboratory shows much higher NDVI values ranging from northwest to north central Kansas. Last year at this time, much of the area was snow covered. Lower NDVI values are most prominent in southwest and south central Kansas, where the winter wheat continues to be less advanced than last year.
Figure 3. Compared to the 27-year average at this time for Kansas, this year’s Vegetation Condition Report for February 7 – February 13, 2017 from K-State’s Precision Agriculture Laboratory much of the state has near-normal vegetative activity. NDVI values continue to increase in the Central and South Central Divisions in response to warmer temperatures. The Southwestern Division isn’t responding as much due to the drought conditions in the region.
Figure 4. The Vegetation Condition Report for the U.S for February 7 – February 14, 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 has retreated to the Northern Plains, although there was a small pocket in central Kansas. The Kansas snow was light and melted within the day of falling. The Sierra Nevada of California continues with tremendous snowpack.
Figure 5. The U.S. comparison to last year at this time for February 7 – February 13, 2017 from K-State’s Precision Agriculture Laboratory shows the split in the snow cover, particularly in the Plains. Snow cover persists in the Northern Plains and is missing in the Southern Plains and the Ohio River Valley.
Figure 6. The U.S. comparison to the 27-year average for the period of February 7 – February 13, 2017 from K-State’s Precision Agriculture Laboratory shows an area of below-average photosynthetic activity in the Intermountain West and the Northern Plains, where snow cover is greatest. Above-average NDVI values are visible in the Midwest from Iowa through Pennsylvania, where snow cover is much more limited and temperatures have been warmer than normal.
Mary Knapp, Weather Data Library
Ray Asebedo, Precision Agriculture
Nan An, Imaging Scientist