Weeds may be unwanted for a number of reasons: they might be unsightly, or crowd out or restrict light to more desirable plants or use limited nutrients from the soil. They can harbor and spread plant pathogens that infect and degrade the quality of crop or horticultural plants. Some weeds are a nuisance because they have thorns or prickles, some have chemicals that cause skin irritation or are hazardous if eaten, or have parts that come off and attach to fur or clothes. As bad as they seem weeds actually serve very important roles in our environment. For example weeds are indicators of problems. The much maligned clover is a great indicator of compacted soil. Treat your soil with Medina Plus and compost to loosen it and the clover will disappear. Weeds also protect the soil. Bare soil will be quickly covered with weeds to hold it in place and keep it cool. As they decompose weeds add valuable organic material to the soil. Weed seeds provide a vital source of nutrition for birds and small animals.