After some trial and error, I've finally developed a livestock duster
that is able to withstand a bison herd's attentions for more than one
season. For those of you who are unfamiliar with this term, a "duster"
is a device that releases a small amount of insecticidal dust whenever
it is rubbed against. It is used for controlling parasitic insects on
livestock.
 |
| A
mild dusting of insecticidal powder on this bison bull's head and horns
is definite evidence of a recent encounter with a rubber tire duster. An
invasive facefly (Musca autumnalis) will have to think twice about attacking this bison. |
 |
| The commercial duster in this photograph has an open bottom and is supposed to be suspended over a narrow passage through which livestock pass. Trying to get a bison to walk through a narrow passage can be difficult, but getting them to walk through a narrow passage with something suspended overhead is next to impossible. As a result I decided to try suspending the device next to some tempting scratching posts in hopes that they would apply the insecticidal powder while rubbing against the posts. For the first month or so the bison seemed highly suspicious of the duster and would keep their distance even when I placed a salt block below the duster. Eventually, though, the herd began to use the post for scratching and even enjoyed using it. The bag, however, wasn't up to the task and was in shreds after a few weeks. |
The following photographs illustrate my development of a rubber tire bison duster that seems to work quite well.
 |
| My first version of the rubber tire duster consisted of half of an old car tire fastened to a wooden post with a burlap bag filled with insecticidal powder suspended inside the tire. Initially, this design worked quite well. Bison seemed to find the texture and shape of a rubber tire ideal for rubbing against. At the same time the tire does a good job of shielding the burlap bag against rain and preventing the bison from ripping the burlap bag apart with their horns. |
 |
| As it turned out, using an old car tire was a mistake as the tire was too weak to withstand abuse from the bison. This duster began to fall apart after one season. |
 |
| My latest version of duster makes use of an entire tire. Utilizing the entire tire gives the bison more to scratch with and also reduced the amount of cutting I needed to do with a reciprocal saw. The side walls on these tires were extremely easy to cut through, but the single cut across the steel belted tread was much more difficult. In all,
four dusters were constructed from the rubber tires that had recently
been replaced on my truck. |
 |
| Each burlap bag was approximately six inches tall and one foot long with a six inch opening at the top into which the insecticidal powder can be poured. I found that bags made from a single layer of burlap allow too much powder to pass through the bag too quickly, so it's best to use a double layer of burlap for each bag. Each tire contains two burlap bags. |
 |
| A diagonal view of one of the tire dusters gives a good idea of how the tire is fastened to a post. |
 |
| A bison dozing in the midday sun after sparring with the duster. |
