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 February 2 – 8 from K-State’s Precision Agriculture Laboratory shows that the area of highest biomass production continues to spread northward from Harper and Sumner counties. Favorable moisture and milder-than-normal winter temperatures has accelerated growth in these areas. The very low NDVI readings in the Northwestern Division are directly related to the heavy snow received there. Amounts of 6 or more inches were common, with the highest totals reaching 17 inches in Decatur County.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for February 2 – 8 from K-State’s Precision Agriculture Laboratory shows much of the state with higher photosynthetic activity. The largest area of decreased vegetative activity is in the Northwestern Division. This is mainly the result of snow cover from the winter storm that left snow totals in the 6 – 12 inch range.
Figure 3. Compared to the 27-year average at this time for Kansas, this year’s Vegetation Condition Report for February 2 – 8 from K-State’s Precision Agriculture Laboratory shows that most of the state continues to show above-average photosynthetic activity. The central parts of the state have the largest areas of above-average photosynthetic activity as moisture continues to be favorable. Temperatures have been close to average for the week, with colder conditions in the west and warmer conditions in the east. As mentioned in the comments for the previous year comparison map in Figure 2, the reduced vegetative activity in northwest Kansas is due to the February 3rd snowstorm.
Figure 4. The Vegetation Condition Report for the U.S for February 2 – 8 from K-State’s Precision Agriculture Laboratory shows that the highest level of photosynthetic activity is in the Deep South, where favorable temperatures continue. Low NDVI readings in the Pacific Northwest are actually very positive as that indicates a substantial snowpack. Lingering impacts of the December flooding continue to be visible in the reduced vegetative activity in the lower Mississippi River Valley.
Figure 5. The U.S. comparison to last year at this time for the period February 2 – 8 from K-State’s Precision Agriculture Laboratory shows that lower NDVI values are most evident in the Pacific Northwest, while much higher NDVI values are visible in the Great Lakes region. Snow is the major driver for both. The Great Lakes area continues to have a low-snow season, while the Pacific Northwest has a higher snow pack than last year. This has resulted in significant drought relief, although much more precipitation is needed.
Figure 6. The U.S. comparison to the 27-year average for the period February 2 – 8 from K-State’s Precision Agriculture Laboratory shows much lower NDVI readings along the West Coast. The decrease is due largely persistent stormy weather and attendant clouds along the coast. The impact of the East Coast blizzard at the end of January is also clearly visible as reduced NDVI readings, although the coverage is shrinking. The increased NDVI readings in eastern Montana and North Dakota are of concern. Snow pack in these areas is below average (snow coverage results in low NDVI readings) and abnormally dry conditions continue to expand in the area.

Mary Knapp, Weather Data Library

Ray Asebedo, Precision Agriculture

Nan An, Imaging Scientist