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 July 28 – August 10 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that the highest biomass production is in eastern Kansas. The Republican River Valley is clearly visible, as are the high NDVI values in Brown and Doniphan counties along the Missouri River Valley. Favorable soil moisture and moderate temperatures have favored biomass production in these areas.
Figure 2. Compared to the previous year at this time for Kansas, the current Vegetation Condition Report for July 28 – August 10 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows parts of southwest and south central Kansas have lower photosynthetic activity. These areas did not have as much moisture in recent weeks as counties farther west, and the sandy soils don’t provide as much storage capacity. In contrast the North Central Division has had more favorable conditions this year. Last year, the divisional average precipitation was just 32 percent of normal in July. This year the division averaged 101 percent of normal for July, and is currently 114 percent of normal for the April-August 13th period.
Figure 3. Compared to the 26-year average at this time for Kansas, this year’s Vegetation Condition Report for July 28 – August 10 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that most of the state has at or above-average photosynthetic activity. The North Central and Northeastern Divisions have the greatest activity. This is partly due to favorable growing conditions and partly due to delayed crop development. This delay means more of the vegetation is in the most active growth period, rather than the reduced activity that comes as the crop matures. The area of south central Kansas just south of the Arkansas River has the lowest photosynthetic activity. Crops in this area are slightly ahead of average development and field preparation for winter wheat has begun.
Figure 4. The Vegetation Condition Report for the Corn Belt for July 28 – August 10 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that greatest photosynthetic activity is concentrated from northeastern Nebraska through Iowa, southern Minnesota and into Illinois. Favorable moisture conditions have resulted in increased photosynthetic activity. In Iowa, crops continue to be close to 80 percent in good to excellent condition.
Figure 5. The comparison to last year in the Corn Belt for the period for July 28 – August 10 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows much of the region has higher photosynthetic activity. This is partly due to a delay in development, with vegetation running later this year. Growing conditions have also 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 July 28 – August 10 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows most of the region has average to above-average biomass production. Favorable growing conditions have prevailed for most of the season. This is most noticeable in western South Dakota and the Nebraska Panhandle.
Figure 7. The Vegetation Condition Report for the U.S. for July 28 – August 10 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that the highest photosynthetic activity is centered in the Upper Midwest. Lower NDVI values are noticeable in the Southeastern U.S., particularly in Georgia and South Carolina, where drought conditions continue to intensify.
Figure 8. The U.S. comparison to last year at this time for the period July 28 – August 10 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that lower NDVI values are most evident in Oregon and northern California. On the eastern side of the mountains in Northern California there is a slight increase in vegetative activity due to summer rains. This does not mark an end to the intense drought in this region.
Figure 9. The U.S. comparison to the 26-year average for the period July 28 – August 10 from K-State’s Ecology and Agriculture Spatial Analysis Laboratory shows that the west continues to have lower than-normal photosynthetic activity, while the central and eastern U.S. have generally higher-than-average values. There is a distinct gradient in the southeast, particularly from Georgia through South Carolina. This marks an area of expanding drought.
Mary Knapp, Weather Data Library
Kevin Price, Professor Emeritus, Agronomy and Geography, Remote Sensing, GIS
Nan An, Graduate Research Assistant, Ecology & Agriculture Spatial Analysis Laboratory (EASAL)