2016-09-09

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 30 – September 5, 2016 from K-State’s Precision Agriculture Laboratory continues to show high NDVI values across the eastern third of the state. Low NDVI values are most visible in parts of northwest and west central Kansas. Vegetation hasn’t responded yet to the latest rainfall, which exceeded 2 inches in parts of the region.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for August 30 – September 5, 2016 from K-State’s Precision Agriculture Laboratory shows vegetative production higher across most of the state. The pockets of decreased photosynthetic activity are in areas where heavy rain and cloud cover masked the vegetative activity.
Figure 3. Compared to the 27-year average at this time for Kansas, this year’s Vegetation Condition Report for August 30 – September 5, 2016 from K-State’s Precision Agriculture Laboratory shows the area of below-average vegetative activity in northwest Kansas has shifted west into Cheyenne and Sherman counties, with a secondary area in Washington County in northeast Kansas. The below-average NDVI values in Washington County 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 August 30 – September 5, 2016 from K-State’s Precision Agriculture Laboratory shows the highest NDVI values are in the western Corn Belt, particularly Minnesota and Wisconsin. Favorable rainfall and more seasonal temperatures continue to favor photosynthetic activity across the region. Low NDVI values stand out across Florida and Georgia. That region is still experiencing high waters/flooding from the recent rains.
Figure 5. The U.S. comparison to last year at this time for August 30 – September 5, 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 the region. In contrast the lower NDVI values in eastern Wyoming, western Nebraska, and much of South Dakota are due to the lingering drought in these areas. There is a small pocket of much higher vegetative activity in northern California, where favorable rains have reduced some of the long-term drought impacts in the region.
Figure 6. The U.S. comparison to the 27-year average for the period August 30 – September 5, 2016 from K-State’s Precision Agriculture Laboratory shows areas of below-average NDVI readings in the Desert Southwest. Onset of the monsoon season has resulted in heavy rains and persistent clouds in the area. Where the rains and clouds have moved out of Arizona, higher NDVI values are visible. Similar patterns can be seen along the Gulf Coast and the mid-Atlantic. Rains from the recent tropical systems have resulted in flooding issues. Concerns are increasing that continued wet weather will result in harvest delays in the Corn Belt.

Mary Knapp, Weather Data Library
mknapp@ksu.edu

Ray Asebedo, Precision Agriculture
ara4747@ksu.edu

Nan An, Imaging Scientist
an_198317@hotmail.com