2016-08-12

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 August 2 – August 8, 2016 from K-State’s Precision Agriculture Laboratory continues to show high NDVI values across the eastern third of the state. The low NDVI values in the southwest and south central areas are due to heavy rains in the area. The Southwest Division average is almost double the normal rainfall for this period, while the South Central Division had more three times the normal rainfall amount. The highest NDVI values are along the Missouri River in Brown and Doniphan counties. It is also interesting to see the higher NDVI values continue to outline the Republican River in north central Kansas.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for August 2 – August 8, 2016 from K-State’s Precision Agriculture Laboratory shows much higher photosynthetic activity in the central areas of the state. The greatest increase in photosynthetic activity continues to be in western Kansas. Rainfall has been well distributed in the region and crop progress continues ahead of last year at this time. Low NDVI values in south central and extreme southwest Kansas are due to the rains and heavy cloud cover this year.
Figure 3. Compared to the 27-year average at this time for Kansas, this year’s Vegetation Condition Report for August 2 – August 8, 2016 from K-State’s Precision Agriculture Laboratory shows below-average vegetative activity is most evident in parts of northwest Kansas. The much below-average NDVI values in southwest and south central Kansas are due to persistent cloud cover in these areas.
Figure 4. The Vegetation Condition Report for the U.S for August 2 – August 8, 2016 from K-State’s Precision Agriculture Laboratory shows high NDVI values in the western Corn Belt, particularly Iowa and eastern Nebraska. Favorable rainfall and more seasonal temperatures favored photosynthetic activity across the region. In contrast, the western High Plains of South Dakota, eastern Montana, and eastern Wyoming continue to have reduced vegetative activity as drought intensifies in these areas.
Figure 5. The U.S. comparison to last year at this time for August 2 – August 8, 2016 from K-State’s Precision Agriculture Laboratory shows that lower NDVI values are visible across much of the Southern U.S. west of the Rockies. Persistent rain and cloud cover have masked vegetative activity in the region. In contrast the low NDVI values in eastern Wyoming, western Nebraska, and much of South Dakota are due to the increasing drought in these areas.
Figure 6. The U.S. comparison to the 27-year average for the period August 2 – August 8, 2016 from K-State’s Precision Agriculture Laboratory shows areas of below-average photosynthetic activity in the Desert Southwest. Onset of the monsoon season has resulted in heavy rains and persistent clouds in the area. Similar, though less extreme, patterns can be seen along the Gulf Coast and the mid-Atlantic. In Mississippi, producers are reporting lush grass and mushy ground from the wet conditions.

Mary Knapp, Weather Data Library
mknapp@ksu.edu

Ray Asebedo, Precision Agriculture
ara4747@ksu.edu

Nan An, Imaging Scientist
an_198317@hotmail.com