By: Jennifer Davit
We are often asked to help identify native seedlings versus weeds in new seed installations. Distinguishing between the species you are trying to grow from the undesirable species is difficult, but there are a few tools that can help. Knowing which species to look for first and having an idea of the weed species found in your area are good starting points.
The first species we typically see emerge from a spring seeding are Partridge Pea, Purple Coneflower and Black-eyed Susans. The Missouri Prairie Foundation's Grow Native website is a great resource for identifying the initial growth of many native seeds. Their website shares great images of the seedlings in multiple phases, so you can easily identify the species growing in your space. The Partridge Pea is easy to distinguish by its pinnately compound leaf. Purple Coneflowers have pubescent or fuzzy leaves, which come to a point at the tip. Black-eyed Susans have very fuzzy or pubescent leaves. They also have a different vein pattern in the leaves and typically have shorter petioles (the part which attaches the leaf to the stem) than Purple Coneflowers.
Knowing the most common weeds in your area is also helpful in distinguishing the plants you want to keep from those you want to remove. Weeds vary greatly from one location to the next, as well as seasonally, so having a good comprehensive resource is essential. I rely on Weeds of North America by Richard Dickinson and Frances Royer. It is a comprehensive text that that includes information regarding the "reason of concern' for each species, which help to guide you in the best management practice for eradication of that species. Excellent images also accompany the well-written text. The Midwest Invasive Plant Network provides a comprehensive listing of invasive plants that can help you identify some of the worst weeds in this region. Each state's Department of Natural Resources also maintains an invasive species list and that is a good place to learn about the worst weeds your area. Taking a little time to learn about these problematic species will help you manage your own native seed installation, and also help develop an appreciation for natural areas that free of these species.
As for ways to manage the weeds, that depends on a number of factors that are specific to each site and based on your objectives for the site. Until plants are established, we do not recommend using any herbicides, as young seedlings can be sensitive to even the smallest amount of herbicide. They typical management methods used in the first season involve hand pulling the weeds and removing the flowers of any weeds before they go to seed. Once plants are established, organic or synthetic herbicides can be used to treat the undesirable weeds. The key is to focus your efforts on removing the undesirable species before they mature and are more difficult to remove.
We hope these tools help you manage your native seeding and guide you in the best management practices. You will find that some time and effort spent managing your native wildflower planting will provide benefits for years to come. If you have questions, as always, Ask the Prairie Guys!