Most roses and citrus you buy or already are growing in your yard are grafted. Grafting into a different rootstock makes the plant hardier. But you have to watch for suckers. That is a part of the rootstock that grows from below the graft. It's usually right out of the ground or on the trunk low to the soil. If you know you plants well, you'll notice when something looks different. On a rose it is usually Dr. Huey rootstock which is a once (Spring) blooming magenta semi-double climber. You'll see spindly growth with smaller leaves that grow fast and usually get taller than your named/purchased/desirable rose. On a Citrus, it's thick branches with super wicked thorns. On both species it is important to remove those suckers either by cutting or breaking. If you do not, the rootstock may become so vigorous that the grafted part of the plant will die.