Cut each pita bread into 8 triangle pieces to look like tree sections. Lightly toast the pita triangles in the oven at 350°F for about 5 minutes until they are a little crispy but not too hard.
Scoop out the avocados into a medium bowl and mash them with a fork until smooth.
Add the lemon juice, minced garlic, salt, and pepper, and mix everything together.
Spread a good amount of the mashed avocado on each toasted pita triangle.
Put the halved cherry tomatoes on top of the avocado, arranging them like decorations on a tree.
Put the pita trees on a serving plate.
Serve these festive avocado pita tree appetizers right away, or keep them in the fridge until you are ready to eat.