I have used milk to fight fungus with limited success. Whole ground (horticultural) cornmeal works much much better. It does not do anything for the grass but it is a favorite growing medium for another beneficial fungus called Trichoderma. Trichoderma fungus literally eats harmful fungi such as the Brown Spot fungus. As far as molasses and grubs are concerned, molasses will do nothing about them. All molasses is, is carbohydrates and soil microbes feed on the carbohydrates and multiply their numbers which is an excellent thing. There may be soil microbes that attack grubs but I don't know of any. The absolute best remedy for grubs are beneficial nematodes, the kind that come on the little blue sponge one buys at a nursery. This time of year the grubs are full grown and are not feeding on the grass roots. Only the small young grubs do the damage. When you see June Bugs in the spring that is the time to apply the nematodes. Beneficial nematodes also control or eliminate most all soil born pests from fleas to earwigs to ants etc. but do not harm earthworms. One applies the cornmeal at regular intervals. Molasses should also be used on a regular basis.
