Question: Flat patches of yellow flowers are spreading more and more in the woodsy area of my yard. The flowers are buttercup yellow but not cupped. The leaves are glossy green. I'm afraid they will take over my woods.

Answer: They will. You have Lesser Celandine, a non-native invasive flower forming impenetrable mats which overrun native species. It greens up very early in spring, then goes dormant over the summer. Its small bulblets or tubers easily break off their roots to start new plants. If you try to dig it up, be sure to shovel up the whole clump. A systemic herbicide containing glyphosate works well on the solid mats.

A resource from Ellen Nibali and Jon Traunfeld of the University of Maryland Extension. For free answers and info about gardens and pest control, call The Home & Garden Information Center hotline at 800-342-2507 or visit www.hgic.umd.edu.