via The Bradley Method.
Strategy. The basis of this method is the native species ability to recolonize by tipping the ecological balance away from the weeds and toward the native plants. If one begins by clearing out the weeds from the most heavily infested areas, the weeds will come right back because they are given ideal conditions: bare, disturbed soil exposed to direct sunlight. But, by working a little at a time, from the strongholds of natural vegetation towards the weeds, the native vegetation is favored and its natural regenerative power will prevail over the weeds.
Plan of Work
In this sequence the Bradleys designed work for one person to follow, working from the best stand of native vegetation to the worst infestation of weeds. By keeping the sequence always the same, it can be followed by any number of people in any number of places.
1. Prevent Deterioration of Good Areas. Start by getting rid of weeds that occur singly or in groups of four or five. Check once or twice a year for missed weeds.
2. Improve tithe Next Best. Choose a place that you can visit easily and often, where the native vegetation is pushing against a mixture of weeds and natives, preferably not worse than one weed to two natives. Start with a strip about 12 feet wide and no longer than you can cover about once a month during the growing season. If this boundary is on a steep slope that might erode, clear a number of patches instead, but still no more than 12 feet from the vigorous native vegetation. Let a few months go by before you lengthen the strip. Your experience will dictate whether to make the strip longer or shorter.
3. Hold the Advantage Gained Resist the temptation to push deeper into the weeds before the regenerating natives have stabilized each cleared area. The natives need not be very tall but should form a dense ground cover. The Bradleys think excluding light from the ground is very important since weed seedlings consistently appear in bare soil at the edges of paths and clearings even when relatively undisturbed and surrounded by dense native vegetation.
4. Cautiously Move into the Really Bad Areas When the new growth consists almost entirely of native species with only a few weeds, it is safe to move further into the weeds. Don’t start to clear a block of solid weeds until you have brought the good native vegetation right up to that area. Solid infestations of weeds can be worked on at the edges by forming peninsulas of weeds, small clearings less than six feet in diameter. Also, spot weeding, removing a single large weed plant next to a native plant in the middle of a solid weed infestation, will bring remarkable results by allowing the native plant to grow much faster. There is no reason to hurry this process; much more is gained by allowing the native plant to grow well before removing another adjacent weed.