2017-04-21

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 April 11- April 17, 2017 from K-State’s Precision Agriculture Laboratory shows a continued increase in vegetative activity along the Arkansas River in southwest Kansas into south central Kansas. Only light activity is visible to the east of the Flint Hills.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for April 11 – April 17, 2017 from K-State’s Precision Agriculture Laboratory lower NDVI values across most of Kansas. The winter wheat is less advanced this year than last, particularly in western Kansas, where dry fall conditions hampered establishment. The greatest increase in vegetative activity is in northeast Kansas, and extreme west central Kansas.
Figure 3. Compared to the 27-year average at this time for Kansas, this year’s Vegetation Condition Report for April 11 – April 17, 2017, from K-State’s Precision Agriculture Laboratory much of the state has below-average photosynthetic activity. The highest NDVI values are in the central and west central parts of the state, where precipitation has been more favorable. The lingering impact from the dry conditions last fall is most visible in southwest Kansas and in the Flint Hills in eastern Kansas.
Figure 4. The Vegetation Condition Report for the U.S for April 11 – April 17, 2017 from K-State’s Precision Agriculture Laboratory shows the region of highest NDVI is 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. As of April 1st, the snow depiction has been dropped, since the snow season is largely over.
Figure 5. The U.S. comparison to last year at this time for April 11 – April 17, 2017 from K-State’s Precision Agriculture Laboratory again shows the impact that split in the snow cover has caused this year. Much lower NDVI values prevail in the Pacific Northwest. The northern Rockies are showing higher NDVI values as the snow pack is rapidly retreating. The South has much higher NDVI values, due to warmer-than-normal temperatures and favorable precipitation.
Figure 6. The U.S. comparison to the 27-year average for the period of April 11 – April 17, 2017 from K-State’s Precision Agriculture Laboratory shows below-average photosynthetic activity in the Pacific Northwest, where continuing storm systems have masked vegetative activity. Below-average NDVI values are also present in the South from Texas to the Ohio River Valley, where continued rain has masked vegetative activity. Higher-than-average vegetative activity is present in the Northern Plains and northern Rockies as the snow pack continues to retreat rapidly.

Mary Knapp, Weather Data Library
mknapp@ksu.edu

Ray Asebedo, Precision Agriculture
ara4747@ksu.edu

Nan An, Imaging Scientist
an_198317@hotmail.com