If you're seeing the circular diameter of each grass clump in the population, try increasing the number of grass clumps by reducing the value of the "Object spacing in a,b" in the population. You can introduce some position randomness to the grass clumps via the "Spacing variation in a,b", and you can randomly scale the grass clump instances via the "Minimum scale" and "Maximum scale" parameters under the Scale tab.
The image below is using only one grass clump object from Mr. Lamppost's grass pack.
