Center:
Buser, Michael. Image Number K11169-3. May 2004. USDA Agricultural Research Service Office of Communications. Image Gallery. Photograph. https://www.ars.usda.gov/oc/images/photos/may04/k11169-3/. Copyright-free, public domain. Accessed July 25 2019.
Outside clockwise from lower right:
Johnson, Jason, NRCS, Iowa. OatSudangrass_1089. September 25, 2013. Photograph. https://www.flickr.com/photos/iowanrcs/9953908723/. All rights reserved, used with permission. Accessed July 25 2019.
USDA NRCS, Montana. Erosion29. April 1981. Photograph. https://www.flickr.com/photos/160831427@N06/38856826241/in/album-72157690579577215/. Copyright-free, public domain. Accessed July 25, 2019.
USDA NRCS, Montana. Erosion56. May 1984. Photograph. https://www.flickr.com/photos/160831427@N06/38856926691/in/album-72157690579577215/. Copyright-free, public domain. Accessed July 25, 2019.
USDA NRCS, Oregon. Substation Fire Wind Erosion. August 3, 2018. Photograph. https://www.flickr.com/photos/nrcs_oregon/43830972371. Licensed under Creative Commons by Attribution-NoDerivs 2.0 Generic (CC BY-ND 2.0) https://creativecommons.org/licenses/by-nd/2.0/. Accessed July 25, 2019.