Targeted livestock grazing is traditionally used to manage weedy vegetation or undesirable vegetation, gaining popularity over the past 10 – 15 years. Similar to targeted grazing of livestock, wildlife may be trained or enticed to eat undesirable vegetation. The purpose of our study was to evaluate white-tailed deer consumption of Canada thistle (Cirsium arvense) using two separate feeding studies on Camp Grafton North, a National Guard Training Center near Devils Lake, North Dakota. The first study took place in 2013 and 2014. Canada thistle was ground using a small Wiley mill and pelleted at different concentrations (25%, 50%, or 75%) with a concentrated feed mixture (corn, soybean meal, molasses). White-tailed deer were provided the pellets of different thistle concentrations over a week long timeframe. Data was collected to observe total percent of consumed pellets for each concentrate level. The results show that all three pellet types were consumed. However, the 25% and 50% pellets were consumed at a slightly higher rate than the 75% pellets. In 2014, we conducted a second study measuring the height of Canada thistle plants before and after an application of Raffinate molasses or Day Tank (regular) molasses. The Canada thistle plants were separated into three categories: healthy (none to minimal consumption), partially consumed, and mostly consumed plants. There were few changes in the results between the before and after heights of the control across all three plant categories. However, the Raffinate molasses created a noticeable loss of healthy plants (82.5%) with a gain of partially (9.9%) and mostly consumed (72.6%) plants . The data from the Day Tank shows a loss of healthy plants (68.4%) and a gain in both partially (19.6%) and mostly consumed (48.8%) plants. More research is needed to determine if white-tailed deer can be used as a biological control for Canada thistle.
Oral presentation and poster titles, abstracts, and authors from the Society for Range Management (SRM) Annual Meetings and Tradeshows, from 2013 forward.