Authors: Mary Knapp, Kevin Price, Nan An
K-State’s Ecology and Agriculture Spatial Analysis Laboratory (EASAL) produces weekly Vegetation Condition Report maps. These maps can be a valuable tool for making crop selection and marketing decisions.
Two short videos of Dr. Kevin Price explaining the development of these maps can be viewed on YouTube at:
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 26-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.
NOTE TO READERS: The maps below represent a subset of the maps available from the EASAL group. If you’d like digital copies of the entire map series please contact Nan An at
firstname.lastname@example.org and we can place you on our email list to receive the entire dataset each week as they are produced. The maps are normally first available on Wednesday of each week, unless there is a delay in the posting of the data by EROS Data Center where we obtain the raw data used to make the maps. These maps are provided for free as a service of the Department of Agronomy and K-State Research and Extension.
The maps in this issue of the newsletter show the current state of photosynthetic activity in Kansas, the Corn Belt, and the continental U.S., with comments from Mary Knapp, assistant state climatologist:
Figure 1. The Vegetation Condition Report for Kansas for September October 6 – 19 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that the highest biomass production is a small pocket of activity along the Arkansas River in southwest Kansas. Irrigated alfalfa is a major product in the region. There is an area of increased photosynthetic activity in northeast Kansas, where rainfall continues to be higher than average. Favorable soil moisture and moderate temperatures resulted in increased biomass production in these areas. Very low NDVI values are visible in Trego, Ellis, Rush, and Ness counties and have expanded into Pawnee and Barton counties, where drought conditions have intensified.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for October 6 – 19 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows much of the state with lower photosynthetic activity. Only the Southwest and South Central Divisions have similar to slightly higher photosynthetic activity. These areas continue have beneficial moisture, while the rest of the state has been dry. This does not show the impact of the rains that fell this week as it will take several weeks for the impacts to be visible.
Figure 3. Compared to the 26-year average at this time for Kansas, this year’s Vegetation Condition Report for October 6 – 19 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that most of the state continues to show near-average photosynthetic activity. While much of the below-average photosynthetic activity is concentrated on the boundaries of the Western and Central Divisions, pockets are visible in northeast, east central and southeast Kansas. These areas continue to miss most of the storm systems, and areas of moderate drought and abnormally dry conditions continue to expand.
Figure 4. The Vegetation Condition Report for the Corn Belt for October 6 – 19 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that greatest photosynthetic activity is concentrated in the southern parts of the region. Favorable moisture conditions have resulted in high photosynthetic activity. Lower NDVI values are present from North Dakota through Iowa to Illinois and Ohio, as crops continue to mature.
Figure 5. The comparison to last year in the Corn Belt for the period for October 6 – 19 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows lower photosynthetic activity along the Central Plains, as an extended dry period has slowed plant development, particularly with winter grains, and drought conditions intensify. There is a small area of higher NDVI values in central South Dakota and eastern Ohio where moisture has been more favorable this year.
Figure 6. Compared to the 26-year average at this time for the Corn Belt, this year’s Vegetation Condition Report for October 6 – 19 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows most of the region has average biomass production. Above-average photosynthetic activity can be seen in the Northern Plains, where temperatures have continued mild and moisture has been favorable. Central Illinois through western Kansas stand out with lower NDVI values as warmer-than-average temperatures and low precipitation stress vegetation.
Figure 7. The Vegetation Condition Report for the U.S for October 6 – 19 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows above-average photosynthetic activity east of the Mississippi River, where favorable temperatures have extended the growing season. Lower NDVI values are noticeable in the Ohio River Valley and along the Mississippi River, where crops have matured early. Low NDVI values are also notable along the western Cascades in Oregon, where drought and wildfires continue to affect vegetation.
Figure 8. The U.S. comparison to last year at this time for the period September October 6 – 19 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that lower NDVI values are most evident from the Plains through the Southwest. Crop development in much of the region is ahead of average. In the western U.S., lower NDVI values are visible in eastern Montana and western North Dakota, and much lower in western Washington, which had more favorable precipitation last year. Little change is evident in Oregon and Northern California, where drought remains unchanged from last year.
Figure 9. The U.S. comparison to the 26-year average for the period October 6 –19 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that the Southern Plains has lower-than-normal photosynthetic activity, while the greatest increase in NDVI values is in New England. Mild temperatures in the Great Lakes region have extended the growing season. Lower NDVI values in Texas show the impact of low rainfall in the last few months.
Mary Knapp, Weather Data Library
Kevin Price, Professor Emeritus, Agronomy and Geography
Nan An, former Graduate Research Assistant, Agronomy