Comparative Vegetation Condition Report: July 25 - 31
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 July 25 – July 31, 2017 from K-State’s Precision Agriculture Laboratory shows the greatest vegetative activity continues to be in eastern Kansas, particularly in extreme northeast Kansas. Warm weather has slowed vegetative activity in the west, but a pocket of increased activity is visible in southwest Kansas, particularly south of Garden City, where heavier showers occurred.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for July 25 – July 31, 2017 from K-State’s Precision Agriculture Laboratory shows the greatest change in vegetative activity is in the Central Division. This summer has been hotter and much drier than last and that has resulted in lower vegetative activity.
Figure 3. Compared to the 28-year average at this time for Kansas, this year’s Vegetation Condition Report for July 25 – July 31, 2017 from K-State’s Precision Agriculture Laboratory there is above-average photosynthetic activity in the eastern parts of the state. Wetter-than-normal conditions have favored parts of the west, particularly Wallace County. Meanwhile continued hot, dry weather has stressed vegetation in the central parts of the state.
Figure 4. The Vegetation Condition Report for the U.S for July 25 – July 31, 2017 from K-State’s Precision Agriculture Laboratory shows an area of high NDVI values centered in the Midwest, particularly in southern Missouri and central Illinois. A second area of higher vegetative activity is also visible along the West Coast, where the recent warm weather has yet to have a negative impact. Extremely low NDVI values continue to highlight the severe drought in eastern Montana and western South Dakota.
Figure 5. The U.S. comparison to last year at this time for July 25 – July 31, 2017 from K-State’s Precision Agriculture Laboratory again shows the impact that the split in moisture has caused this year. Much lower NDVI values are visible from eastern Montana through the Dakotas and into the Oklahoma Panhandle. In contrast, eastern Illinois and western Ohio have much higher NDVI values than last year at this time.
Figure 6. The U.S. comparison to the 28-year average for the period of July 25 – July 31, 2017 from K-State’s Precision Agriculture Laboratory shows the drought impacts in the Northern Plains are visible as much below-average NDVI values. In Colorado, parts of Idaho, and the Sierra Nevada of California, the below-average NDVI values are due to monsoon moisture. Parts of the area have been under flood advisories most of the week.
Mary Knapp, Weather Data Library
Ray Asebedo, Precision Agriculture
Nan An, Imaging Scientist