Comparative Vegetation Condition Report: April 5 - 11
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 April 5 – 11, 2016 from K-State’s Precision Agriculture Laboratory continues to show slightly more expansion of the area of highest plant production. The highest NDVI values are still in Sumner and Harper counties. The Flint Hills continue to show relatively low photosynthetic activity.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for April 5 - 11, 2016 from K-State’s Precision Agriculture Laboratory shows vegetative production in the southern half of the state lags behind last year’s level of production at this time. Dry conditions in March and early April have slowed production. In contrast, above-normal moisture in February in the Northwest and North Central Divisions has buffered vegetation in those areas. Lack of moisture as vegetation emerges from dormancy is decreasing photosynthetic activity.
Figure 3. Compared to the 27-year average at this time for Kansas, this year’s Vegetation Condition Report for April 5 – 11 from K-State’s Precision Agriculture Laboratory shows that the area of above-average photosynthetic activity continues to decline. The largest areas with the greatest increase are in central Kansas. Even with the recent cool weather, temperatures continue above normal across the state. An exception to the generally greater photosynthetic activity can be seen in western Barber County. Lack of precipitation has slowed the plant recovery from the fire in that area. The much lower NDVI values in extreme northeast Kansas are just imaging artifacts of the cloud cover from recent rains in those counties.
Figure 4. The Vegetation Condition Report for the U.S for April 5 – 11 from K-State’s Precision Agriculture Laboratory shows high NDVI values much of the West Coast and along the Gulf Coast. Favorable moisture continues to drive active photosynthesis in these areas. A pocket of lower photosynthetic activity can be seen in the middle Mississippi Valley region, where the impact from winter floods is still being felt.
Figure 5. The U.S. comparison to last year at this time for the period April 5 – 11 from K-State’s Precision Agriculture Laboratory shows that lower NDVI values are most evident in Minnesota and Wisconsin, thanks to a late-season snow event. In contrast, much higher NDVI values are visible in New England. Despite the recent snows in this area, the overall snow depth is less than last year, and more vegetation is active.
Figure 6. The U.S. comparison to the 27-year average for the period April 5 – 11 from K-State’s Precision Agriculture Laboratory shows above-average photosynthetic across the Pacific Northwest, where winter moisture has reduced drought impacts. Snow pack from the late-season storms in the Great Lakes region has reduced photosynthetic activity in that area. There is concern in this area about damage to the fruit crop due to recent freezing temperatures.
Mary Knapp, Weather Data Library
Ray Asebedo, Precision Agriculture
Nan An, Imaging Scientist