By Mary Knapp
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. 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 October 11 – October 17, 2016 from K-State’s Precision Agriculture Laboratory shows only light photosynthetic activity. As the growing season comes to an end more vegetation is moving into dormancy.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for October 11 – October 17, 2016 from K-State’s Precision Agriculture Laboratory shows the largest area of higher vegetative activity is in north central Kansas. The delay in sorghum development this year continues to be the major contributor to the higher NDVI values. Slow establishment of winter wheat in the Southwest Division is visible as reduced NDVI values there.
Figure 3. Compared to the 27-year average at this time for Kansas, this year’s Vegetation Condition Report for October 11 – October 17, 2016 from K-State’s Precision Agriculture Laboratory shows a large area of below-average NDVI values in eastern Kansas. This is the result of persistent cloud cover in that area. The below-average vegetative activity in the western half of the state is due to increasing dryness impacting winter wheat establishment.
Figure 4. The Vegetation Condition Report for the U.S for October 11 – October 1, 2016 from K-State’s Precision Agriculture Laboratory shows the area of highest NDVI values is along the coasts where mild temperatures and rains have extended the growing season. Low NDVI values are visible in the Corn Belt and along the Mississippi River Valley, where crop maturity is slightly ahead of average, but harvest has been delayed by wet soils.
Figure 5. The U.S. comparison to last year at this time for October 11 – October 17, 2016 from K-State’s Precision Agriculture Laboratory shows that lower NDVI values are most prominent in the South where drought continues to be an issue. This region missed out on the recent tropical systems.
Figure 6. The U.S. comparison to the 27-year average for the period October 11 – October 17, 2016 from K-State’s Precision Agriculture Laboratory shows the most prominent area of below-average photosynthetic activity is in the South. While the northern areas of this region had rains during this period, the deep South continues to have persistent drought conditions.