This time of year you may notice a new crop of weeds in the lawn. The majority of these newly emerging weeds are cool season annual broadleaf weeds. The most common cool season weeds are chickweed, bittercress and henbit. These weeds germinate starting as early as late August and during the fall seeding season and continue to germinate and develop through the spring. One of the major challenges to aeration and seeding is that when you turn the soil is the viable weed seeds will germinate along with the grass seed with nutrients, light and water. We must be willing to live with some weeds to allow the grass plant to develop before spraying them as most weed control will injure or inhibit seed development. During the late fall visit we spray off all the newly emerged weeds and this year will be applying a pre-emergent to prevent any further germination of these three weeds. The late fall visit is essential for feeding the lawn and helps with root development and food storage for the turf plant next year. Now is grass growing weather as the weather has cooled. The majority of lawns in this region are cool season turf and they prefer this cooler weather.