Partcle Groups are not staying in image area

Hi, I am using an image texture and groups to control the placement of particles (cubes) on a plane. I load the image into the “Textures” panel in the particle settings but the particles (cubes) are not staying "Within’ the image area. Does anyone know what setting allows the cubes (particles) to be contrained to the image area?

Will post a file as soon as I get home. Thnks.

Figured it out. Thanks.