Background Paragraph: In addition to insects, weeds have also been a menace to farmers - just ask anyone with a garden how much they hate weeds. They can quickly compete for water and nutrients needed by other plants. Sure, farmers can use herbicides to kill weeds, but do these chemicals also harm the crops? Can biotechnology help with this issue? Some crops have also been genetically engineered to acquire tolerance to the herbicides - allowing the crops to grow, but killing the weeds. But the lack of cost effective herbicides with a broad range of activity - that do not harm crops - is a problem in weed management. Multiple applications of numerous herbicides are routinely needed to control the wide range of weeds that are harmful to crops. And at times these herbicides are being used as a preventive measure – that is, spraying to prevent weeds from developing rather than spraying after weeds form. So these chemicals are being added to crops. This practice is followed by mechanical and/or hand weeding to control weeds that are not controlled by the chemicals. Crops that are tolerant of herbicides would obviously be a tremendous benefit to farmers ( Figure above ). The introduction of herbicide tolerant crops has the potential to reduce the number of chemicals needed during a growing season, thereby increasing crop yield due to improved weed management and decreased harm to the crops. 
Story: Jamie decided he wants to build a garden in his back yard. He finishes planting a nice crop of tomatoes and zucchini and is very happy with himself. About a month later he checks in on his garden only to see a plethora of weeds has grown with  his crop. The tomato and zucchini plants are much smaller than he expected and some are even dying.
Given Jamie removes all the weeds in his garden, will his plants get more or less nutrients and water? Will increasing the amount of weeds growing in a garden increase or decrease the health of the plants?