 Stiefel Nicholas & Company, Inc., member SIPC and NYSE. Here's Chad Norton, the lawn doctor, with a tip for your lawn. Warmer temperatures have both weeds and grass competing for space in your yard. Dandelions, thistle, clover, morning glory will all be kept under better control when you have us applying pre-emergence and weed control. At the same time, we can feed your grass to make sure it wins the battle and keep it lush and growing all season long.