Q: For years I used a product containing monosodium acid for weed control. Now it’s off the market. What is a substitute?

A: Monosodium methanearsonate (MSMA) was taken off the market a few years ago due to concerns about soil arsenic accumulation. It was very good for grassy weed control. The chemical quinclorac is a substitute and is found in Bayer Lawn Weed and Crabgrass Killer, Ortho Weed B Gon MAX Plus Crabgrass Control and Bonide WeedBeater Ultra.