AERC Funded Noxious Weed Study – Do Horses Introduce Non Native Species onto Trails?

Here is a link to the study on invasive weeds that was published in the December 2008 issue of Endurance News. One of the rides that they used in the study was the Cuyama Oaks XP. The study will be finished in 2009 when the rest of the samples are collected. Below is an excerpt from the study. Click on the above link to read more.

The results of the study showed that non-native weeds did not germinate from hoof debris or manure samples grown in pots, but on average 5.4 % of the hay samples from 20 horse/rider teams at the five endurance rides did contain non-native weeds (Gower 2008). The most prevalent weed was Canadian thistle. However, no non-native weeds germinated from the hay, manure, or hoof debris samples placed on the trails at the five sites. While these results are relevant for many ecosystems in the eastern United States, it is unclear if horses are responsible for introducing non-native weeds in the western United States.