Recently we have been working on and experimenting with vole protection and eradication techniques. In partnership with the university of Virginia Tech we recently planted over 800 pounds of german white seed garlic within the nursery as part of an IPM treatment. Voles, are are discussed a major nuisance to agroforestry and often devastate the root systems of young fruit and nut trees. The 800 pounds was the largest amount we could possibility do on our property and was planted at a spacing of 2 to 4 inches to act as a cover crop rather than a staple food crop. Although we hope to pull a return on wholesaling the garlic the most important part of the planting is the hope that it saves the trees. Amazingly, this influx of bio-material has seemingly kept the voles at bay, in that we have seen a marked reduction of population in the fields. Yet, we have seen some evidence of vole presence in ways that are nerve racking.
Our primary concern is that in plating the garlic we used local hay to mulch down the crop. The mulch required for the garlic has caused two side effects. First, the tree beds seeded with garlic has caused more vole habitat. Two, the hay mulch has served to help protect the new seedlings and if the garlic does its job created an ideal bed for the trees. Because we tilled the area deeply to plant we are also hoping that the reduction of weeds will increase growth rates. Overall, we are encouraged by the initiative but have maintained some reservations.
Is there a second treatment?
The planting of the garlic has us musing on the next steps. In talking with a local farmer juicy fruit gum was proposed. In another discussion we talked to a farmer that added in mint oils to his organic orchard spray. In addition to these treatments, we are also currently researching the spot spraying of organic castor oil into the bed. This is one of the active ingredients in commercial vole repellent and we can not find any literature on toxicity. We are interested in hearing from anyone that has worked with castor oil or garlics to keep these rodents at bay.