Rinse the dry wheat berries under cold water to remove any debris.

In a large pot, bring salted water to a rolling boil. Add the wheat berries and simmer for 50-60 minutes until tender.

Drain and rinse the wheat berries under cold running water, letting them sit in a strainer to remove excess water.

In a large mixing bowl, combine cooled wheat berries, diced tomatoes, canned tuna, and green onions. Gently fold in chopped parsley.

In a small bowl, whisk together olive oil and lemon juice until well-emulsified. Adjust seasoning with salt and pepper.

Pour the dressing over the salad ingredients and toss gently to combine.

Serve immediately or store in an airtight container in the refrigerator for up to 3-4 days.