Comparative Vegetation Condition Report: March 21 - 27
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 March 21 – March 27, 2017 from K-State’s Precision Agriculture Laboratory shows only light photosynthetic activity during the period. The little vegetative production is mainly in south central Kansas, although it continues to expand northward. The low NDVI values in north central Kansas are due to persistent cloud cover.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for March 21 – March 27, 2017 from K-State’s Precision Agriculture Laboratory shows much 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. In north central Kansas persistent cloud cover accounted for reduced NDVI values.
Figure 3. Compared to the 27-year average at this time for Kansas, this year’s Vegetation Condition Report for March 21 – March 27, 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 south central parts of the state, where precipitation has been more favorable. The band of much-below-average NDVI values visible in parts of north central and central Kansas is largely an artifact of persistent cloud cover.
Figure 4. The Vegetation Condition Report for the U.S for March 21 – March 27, 2017 from K-State’s Precision Agriculture Laboratory shows an area of high NDVI in the South, particularly in east Texas and Louisiana. Snow coverage continues to shrink, and was mostly in the Upper Midwest and New England. Parts of Upstate New York had relief from the snow deficit that has been present for most of the winter.
Figure 5. The U.S. comparison to last year at this time for March 21 – March 27, 2017 from K-State’s Precision Agriculture Laboratory again shows the impact that the split in the snow cover has caused this year. Much lower NDVI values prevail from the Pacific Northwest through the Northern Plains and into New England, where snow coverage continues to be much higher this year. The very low NDVI values in the Central Plains and Southeast are due to persistent cloud cover.
Figure 6. The U.S. comparison to the 27-year average for the period of March 21 – March 27, 2017 from K-State’s Precision Agriculture Laboratory shows an area of below-average photosynthetic activity in the Pacific Northwest, where continuing storm systems have masked vegetative activity. Above-average NDVI values are visible in the Midwest from Iowa through Pennsylvania and northward. This is particularly true in central Minnesota and Wisconsin. Warmer-than-normal temperatures and little snow cover has favored early vegetative growth with continued risk of freeze damage.
Mary Knapp, Weather Data Library
Ray Asebedo, Precision Agriculture
Nan An, Imaging Scientist