Some invasive plants take over because they're filling an otherwise unoccupied niche.
Phragmites is one of them.
As a shade-intolerant plant that requires nutrient rich soil, phragmites often proliferates in places that were historically freshwater forested wetlands (and adjacent to tidal estuaries influenced by freshwater flows). It often grows in once we have removed canopy cover and bring in fill.
Once this plant takes over, it chokes out native flora and ecological succession from wet meadow to forest effectively ceases.
Here, we removed a stand of phrag by hand and replaced it with plants including bayberry, red cedar, red maple, and beach plum.
Although follow-up visits are likely necessary, the additional plants should grow and fill in the space left by the phrag, and help to reduce its prevalence long term.
*Heads up*, phrag often grows in areas regulated by federal, state, and local law, so you often need a permit to remove it yourself.