Miss Fido Manners: The rules of canine etiquette extend far beyond the home and out into the neighborhood and community. Dog owners must recognize that their behavior, and that of their pet affects their neighbors -in this case, you- whether they live in a house, a condo or apartment. If the dog-owning public practices consideration and promotes cordial relations, they can be an exemplary neighbors. And you can too, without creating neighbor-to-neighbor conflict.
While Miss Fido understands that your neighbor's dog frequenting your yard is troublesome, you do not detail what he does on premises? Does the dog use your lawn as potty area, get into your garbage cans or scratch at your door because he is in love with your pooch? I ask because it is always better to discuss specific concerns in your communication. Remember, your relationship with her dictates how best to approach her. For example, if you are friendly, go see her; If not, address a friendly note to her on your best stationary. Either way, you should express the problem succinctly, offer a solution to show concern for her and the dog. By doing this, you show you care about the dog and your relationship.
Tell her that at least two or three times a week, you find her pooch in her yard doing what. Remind her that you understand taht dogs can be Harry Houdini escape artists or canine high jumpers. Give her the benefit of the doubt that she doesn't know that he is cavorting around your property because there is a chance that a member of her household is letting the dog out and/or she does not know that her fencing is in need of repair. Ask her to take care of the problem as soon as possible by possible repairing or installing a pet fence. And lastly, mention that a roaming dog could get hit by a car, snatched by dog fighters or others with bad intentions, become ill from eating garbage or plants, or be picked up by animal control. More importantly, tell her that you wouldn't want her to neither worry about her family member nor incur additional expensive on his behalf.
Moreover, always try to maintain a cordial relationship with your neighbors because there is a chance that you may be living next to them longer than the life of your dog!