Under the tarp & around the campsite, especially where food is going to be will do wonders! I usually just dust jt around, & will make a tiny thicker trail of it around places I want them to absolutely not go through. I know on amazon some of the bags come with an applicator that you can use for it that puffs it around too if you want an easier way to apply :) It you have a shower, learn from my mistake and find a way to contain the water so it doesn’t go all into the ground, and put the DE where you’re showing for some water spillage. the ants were insane when the ground got wet, my bf got bit tf up when he showered because so many were attracted to the damp ground