How can I soundproof my yard to muffle the sound of barking dogs?

Are they your dogs?

Not sure what you are asking? Is it some type of sign you are wanting to add to your yard? Are they your dogs? Are you asking how to keep your dogs quiet? dogs have excellent hearing so they bark at things they hear close by or far away...it's their job to let you know and it's your job to keep them from barking incessantly to where it becomes a problem. Dogs left alone for long periods, whether in the house or in the yard will bark. Bored Dogs will bark just not sure about what you are asking..... maybe a solar motion sensor security light

If your neighbor's barking dog is driving you crazy, or your barking dog is driving your neighbor crazy, what happens next depends on your town's ordinances. While public nuisance laws vary, most spell out the specific circumstances under which you can file a complaint against your neighbor or vice versa.

Depending on the municipality, the neighbor must either call and complain or file a formal, written complaint. Generally, the barking dog's owner gets a warning from the animal control officer after the initial complaint. He is given a set amount of time, usually five days to a week, to correct the problem. If there's another complaint, he's likely to face fines. In many jurisdictions, violating a nuisance ordinance is considered a Class 1 misdemeanor.

Odds are that animal control officers are dog lovers and will be willing to work with you. Many municipal websites offer information resolving your dog's barking issue. Phoenix, Arizona, recommends speaking with your neighbor about the nature of the problem, including time of day, duration and any possible reasons for the barking. San Diego, California, advises dog owners not to leave their canines outside if they're not home. Livermore, California, suggests leaving a radio on low volume when you're out to muffle outside noises that might set your dog off. Of course, training your dog, providing him with plenty of exercise or, if necessary, using a bark correction collar can eliminate nuisance barking. If your dog barks because of separation anxiety, a visit to the vet is in order. She might prescribe medication to alleviate the problem.

If you are trying to have your backyard be a quieter space you can plant hedges that may help muffle the noise a bit. Good luck!

After having a new neighbor move in with 2 barking and fighting dogs, I was so frustrated I ordered one of those ultrasonic bark tools..... now they are trained and I don't hear them bark anymore..... peace and quiet at last. I have the hand-held type. I've also heard the one that looks like a birdhouse you hang up work great too.... https://www.amazon.com/s?k=bark+no+more+ultrasonic&crid=1S476VWY0AJEW&sprefix=bark+no+more%2Caps%2C237&ref=nb_sb_ss_i_3_12

Outdoor white noise machines help. There are panels u can add to your fence as well. And if that fails buy a machine that puts out a high frequency sound when barking is heard.