2014-08-15

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:
http://www.youtube.com/watch?v=CRP3Y5NIggw
http://www.youtube.com/watch?v=tUdOK94efxc

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 25-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 nanan@ksu.edu 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, service climatologist:

Figure 1. The Vegetation Condition Report for Kansas for July 29 – August 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that the highest level of vegetative activity continues to be in the northeast, along the Missouri River. There is also high biomass production along the Republican River Valley in Republic, Washington, and Clay counties. Similar high NDVI values can be seen in other river valleys, where the soils haven’t dried out as quickly as in the uplands.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for July 29 – August 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that parts of southwest and south central Kansas have much higher photosynthetic activity. In contrast, much of north central Kansas has much less biomass production than last year.
Figure 3. Compared to the 25-year average at this time for Kansas, this year’s Vegetation Condition Report for July 29 – August 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows southern Kansas, particularly Clark and Comanche counties, has benefitted from the wet conditions in June and July. In contrast, the north central part of the state has much lower-than-normal productivity. Phillips and Rooks counties, in particular, have very low photosynthetic activity. Uneven rainfall distribution was a major factor.
Figure 4. The Vegetation Condition Report for the Corn Belt for July 29 – August 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that biomass production continues to be high in all but the westernmost part of the region. Pockets of low productivity can be seen in parts of central Missouri, southern Ohio, and northern Kentucky. Topsoil moisture in central and southwestern Missouri is reported as more than 50 percent short to very short.
Figure 5. The comparison to last year in the Corn Belt for the period July 29 – August 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that conditions are generally less favorable. A large portion of southern Minnesota, central Missouri, and most of Iowa has much lower photosynthetic activity than last year. The big difference may be in crop progress. In Iowa, corn acreage is reported to be two weeks ahead of the 2013 progress, and more than 75 percent is in good to excellent condition.
Figure 6. Compared to the 25-year average at this time for the Corn Belt, this year’s Vegetation Condition Report for July 29 – August 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that the western portions of the region tend to have above-average photosynthetic activity. In the central portions of the Corn Belt photosynthetic activity is below average.
Figure 7. The Vegetation Condition Report for the U.S. for July 29 – August 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that the highest NDVI values are along the Pacific Northwest. Another high productivity area is in eastern Nebraska. The state saw widespread 1- to 2-inch rainfall last week, and 70 percent of the corn and soybeans are reported to be in good to excellent condition.
Figure 8. The U.S. comparison to last year at this time for the period July 29 – August 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that California stands out for much lower biomass production. The low productivity is also visible along the southern Washington border and into Idaho and Montana. To the east, pockets of lower NDVI values are side by side with higher NDVI values. In many cases, this is dependent on stage of plant development. In Iowa corn progress is 2 weeks ahead of last year at this time.
Figure 9. The U.S. comparison to the 25-year average for the period July 29 – August 11 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that a large portion of the West has much-lower-than-average NDVI values. This corresponds to the exceptional and extreme drought that is prevalent in the area. In the East, the lower NDVI values are mostly a factor of crop stage rather than drought stress.

Mary Knapp, Weather Data Library
mknapp@ksu.edu

Kevin Price, Professor Emeritus, Agronomy and Geography, Remote Sensing, GIS
kpprice@ksu.edu

Nan An, Graduate Research Assistant, Ecology & Agriculture Spatial Analysis Laboratory (EASAL)
nanan@ksu.edu