Removing Bermuda grass from a lawn can be a challenging and ongoing process but a few simple techniques and cultivation practices can eradicate a minor infestation and keep a more serious one at bay. Minor patches can often be controlled by frequent inspection and manual pulling. Large infestations require a combination of tactics aimed at boosting the vitality of the desired grass while preventing the seeding, germination and unwanted spreading of the Bermuda grass. Chemical herbicides are not terribly effective on tough Bermuda grass and will often damage the soil and existing desired grass--making yet more room for the Bermuda. Patience and constant monitoring and maintenance are the keys to gaining the upper hand.
Keep your base and desired lawn grass well fed and well hydrated. A healthy and aggressively growing lawn will help to crowd out the Bermuda grass and shade any seeds from the sun, preventing germination. Water at least once per week, providing an inch of water in one or more watering sessions. More water may be required based on your grass variety and climate. Fertilize the grass several times per year starting in the early spring, according to label recommendations.
Raise the height of you lawnmower blade when you mow. The taller grass will create shadier conditions, preventing the Bermuda grass seed from germinating effectively. Always use a catch on your lawnmower to collect the grass clippings. Bermuda grass throws up large propeller-shaped seed heads and you do not want these to fall back onto the soil to propagate themselves. Never compost Bermuda grass clippings--the seeds can sometimes survive the composting process and colonize where the compost is used, exacerbating your problem.
Inspect the lawn every few days or at a minimum weekly when watering to look for tufts of Bermuda grass runners, stolons and seed heads. After watering the tufts will be easier to pull. Grasp the tuft of grass and runners down at the base with the side of your hand touching the soil and pull straight up and out. This will help you to lift the Bermuda out by the roots. Alternatively, use a weeding fork to dig down and under the roots and lever them up to the soil surface. Discard all of the pulled debris in a seal trash bag.