Agricultural Crops
Some reports indicate that providing an alternative or decoy food source will reduce crop damage caused by crows. An example would be scattering a grain such as whole corn, preferably softened by water, through a field where crows are damaging newly planted corn seedlings. Although this technique has been reported to be helpful in some situations, it has not been well tested. This method also has the potential to "backfire" by drawing more crows to an area that provides free food.
Tree Roosts
Thinning branches from specific roost trees or removing trees from dense tree stands reduces the availability of perch sites and opens the trees to weather effects. Such vegetation management has effectively dispersed starling/blackbird roosts, and the same biological concepts indicate probable effectiveness in dispersing crow roosts. When roosts occur in a small number of landscape trees near homes or along streets, they are usually in fairly dense trees where thinning the branches will reduce the trees’ attractiveness as roosts.
Roosts in tree groves or woodlots usually occur in dense stands of young trees. Removal of about one-third of the trees improves the tree stand, especially if marked by a professional forester or arborist. Such thinning successfully dispersed blackbird/starling roosts from research woodlots in Ohio and Kentucky, and from at least two problem roost sites in Nebraska. In dense cedar thickets, bulldozing strips through the roost site to remove one-third of the habitat has also been successful in dispersing birds, but soil disturbance with this method may be hazardous if soils harbor fungal spores of the human respiratory disease histoplasmosis, so be sure you protect yourself prior to disturbing the soil.
Resources: (online)
Crows
