Rats in the garden are not as easily controlled by traps as rats in the home. Placing traps where other visitors to the garden, such as cats and birds, will not find them may present a problem. Poison placed where rats commute can be somewhat effective, but rats may relocate from crowded areas into areas vacated by the deceased. Poisoned rats are attracted to and die near water, including swimming pools (Ick!)
Sheet metal wider than rats can climb over wrapped around trunks of isolated fruit trees (and adjusted for expansion of the trunk) will obstruct access to rats. Trees that are not isolated may be accessed by limbs of adjacent trees or other structures that extend into the canopy, so sheet metal barriers are not effective.
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