Comparative Vegetation Condition Report: September 20 - 26
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 September 20 – September 26, 2016 from K-State’s Precision Agriculture Laboratory shows a continued decrease in the area of highest NDVI values. Moderate NDVI values continue in the eastern portions of the state, as vegetation begins to go dormant.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for September 20 – September 26, 2016 from K-State’s Precision Agriculture Laboratory shows the largest area of increased vegetative production is in north central Kansas. Currently this area is drought-free, whereas last year there was moderate drought in the area. The pockets of decreased photosynthetic activity from south central Kansas through northeast Kansas are evident in areas where heavy rain and cloud cover during this period this year masked the vegetative activity.
Figure 3. Compared to the 27-year average at this time for Kansas, this year’s Vegetation Condition Report for September 20 – September 26, 2016 from K-State’s Precision Agriculture Laboratory shows below-average vegetative activity is concentrated in the central parts of the state. These low NDVI values are the result of heavy rains and cloud cover in this area. Warm temperatures and seasonal rainfall have favored plant growth across most of the state.
Figure 4. The Vegetation Condition Report for the U.S for September 20 – September 26, 2016 from K-State’s Precision Agriculture Laboratory shows the area of highest NDVI values is in New England, where mild temperatures have extended the growing season. Low NDVI values in Minnesota and Wisconsin correspond to areas of saturated soils.
Figure 5. The U.S. comparison to last year at this time for September 20 - September 26, 2016 from K-State’s Precision Agriculture Laboratory shows lower NDVI values in the upper Midwest, particularly in Minnesota and Wisconsin. Persistent rain continues to mask vegetative activity in these areas.
Figure 6. The U.S. comparison to the 27-year average for the period September 20 – September 26, 2016 from K-State’s Precision Agriculture Laboratory shows below-average photosynthetic activity in the Upper Midwest. Heavy rains and saturated soils have limited photosynthetic activity in that region, particularly as the growing season comes to a close.
Mary Knapp, Weather Data Library
Ray Asebedo, Precision Agriculture
Nan An, Imaging Scientist