Abstract: A device attaches to the trunks of plants and trees to prevent snails from reaching the upper portion of the plant or tree which has leaves and fruit subject to attack from the snails. Embodiments of the device have an inner funnel-shaped sleeve which biases against the tree trunk to provide a sufficiently tight closure to prevent snails from climbing between the trunk and the device. Embodiments of the device have a downward facing surface having a plurality of closely-spaced downwardly facing spike members. These spike members are sufficiently closely spaced so as to substantially or completely prevent snails, including small-sized young snails, from moving across the downwardly facing surface to crawl around the outside of the device to gain access to the upper portion of the tree.