2017-05-26

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, and 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 May 16 – May 22, 2017 from K-State’s Precision Agriculture Laboratory shows slow vegetative development across much of the state. The recent cold weather has slowed vegetative activity in the west. The greatest area of high vegetative activity is in the southeast, where temperatures have been consistently warmer than the rest of the state.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for May 16 – May 22, 2017 from K-State’s Precision Agriculture Laboratory shows a mix of conditions. In parts of southwest Kansas much lower NDVI values are visible. This is particularly true in Meade and Clark counties. The winter wheat is less advanced this year than last, particularly in western Kansas, where dry fall conditions hampered establishment and recent cold weather has slowed development. Other areas reflect the cooler temperatures this year. Higher NDVI values in the east, particularly in the Flint Hills, reflect the more favorable moisture received this year.
Figure 3. Compared to the 27-year average at this time for Kansas, this year’s Vegetation Condition Report for May 16 – May 22, 2017 from K-State’s Precision Agriculture Laboratory much of the state has below-average vegetative activity. The wetter-than-normal conditions have slowed spring planting in the northern parts of the state, and excessive moisture has dampened vegetative activity in the Southeastern Division.
Figure 4. The Vegetation Condition Report for the U.S. for May 16 – May 22, 2017 from K-State’s Precision Agriculture Laboratory shows the highest NDVI values are confined to the South, particularly in east Texas and Louisiana. A second area of higher vegetative activity is also visible along the West Coast, where wet conditions continue. Low NDVI values are visible along the central Mississippi River Valley, where flooding continues to be an issue.
Figure 5. The U.S. comparison to last year at this time for May 16 – May 22, 2017 from K-State’s Precision Agriculture Laboratory shows the impact that split in the snow cover has caused this year. Ample moisture from the winter snows has resulted in higher vegetative activity in the West. Much lower NDVI values are visible in the Great Lakes due mainly to persistent cloud cover.
Figure 6. The U.S. comparison to the 27-year average for the period of May 16 – May 22, 2017 from K-State’s Precision Agriculture Laboratory shows below-average photosynthetic activity concentrated in the central region, from Texas through the Great Lakes. This is due mainly to persistent cloudy, wet weather. The lower-than-average NDVI values in Florida, Georgia, and Alabama reflect the persistent drought in this region.

Mary Knapp, Weather Data Library
mknapp@ksu.edu

Ray Asebedo, Precision Agriculture
ara4747@ksu.edu

Nan An, Imaging Scientist
an_198317@hotmail.com