2016-09-16

Authors: Mary Knapp, Ray Asebedo, Nan An

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 6 – September 12, 2016 from K-State’s Precision Agriculture Laboratory continues to show high NDVI values across the eastern third of the state. An exception can be seen in the Kansas City metro area. This is a result of the heavy rains that inundated the area early in the month.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for September 6 – September 12, 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. Pockets of decreased NDVI readings are evident in areas where heavy rain and cloud cover 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 6 – September 12, 2016 from K-State’s Precision Agriculture Laboratory shows the area of below-average vegetative activity is confined to the eastern counties. These low NDVI values are the result of heavy rains and cloud cover in this area. Moderate 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 6 – September 12, 2016 from K-State’s Precision Agriculture Laboratory shows high NDVI values in the western Corn Belt, particularly Minnesota and Wisconsin. Favorable rainfall and more seasonal temperatures continue to favor photosynthetic activity across the region. More vegetative activity has become visible in east Texas and Louisiana, although the region is still experiencing high waters/flooding from rains in August.
Figure 5. The U.S. comparison to last year at this time for September 6 - September 12, 2016 from K-State’s Precision Agriculture Laboratory shows that lower NDVI values continue across much of the Southern U.S. west of the Rockies. Persistent rain and cloud cover continues to mask vegetative activity in Louisiana. Moderate drought conditions persist in the Carolinas. In contrast, the low NDVI values slicing from the Dakotas through western Missouri are due to clouds this year.
Figure 6. The U.S. comparison to the 27-year average for the period September 6 – September 12, 2016 from K-State’s Precision Agriculture Laboratory shows areas of below-average photosynthetic activity in California, where drought persists. The slice of below-average NDVI values from the Dakotas through western Missouri into Arkansas and Louisiana are the result of persistent clouds in the area. Much of the Hill Country in Texas shows higher-than-average vegetative activity due to favorable rains and temperatures.

Mary Knapp, Weather Data Library
mknapp@ksu.edu

Ray Asebedo, Precision Agriculture
ara4747@ksu.edu

Nan An, Imaging Scientist
an_198317@hotmail.com