Garden Q&A.(Knight Ridder Newspapers)

Q. How do I get rid of this bright green weed with heart-shape leaves that comes up in spring, gets only a few inches high, has little yellow flowers, turns sickly yellow and dies pretty soon _ and is taking over?

Answer: If I could patent an environmentally reasonable way to get rid of lesser celandine _ truly get rid of _ I could buy three of everything in all the overpriced catalogs and have enough left over to acquire a small Caribbean island. Not only that, my garden would fairly sing with joy.

Lesser celandine (botanically Ranunculus ficaria, the bad boy of the buttercup family) is from Europe and is serious problem that threatens native wildflowers as well as home gardens.

Its reproductive capacities are boggling. The inadvertent arrival of one plant in your garden (say, in the soil of that gift astilbe from your neighbor) can result in a major problem in a few years. Each flower produces a host of seeds, but worse are the bulbils that form at the axils of the fleshy stems. When the foliage ripens and dies, typically in June, the bulbils are loosed, take root and produce near-mature plants the next year. Plus, the root system of the plants is a cluster of many tiny tubers; if disturbed in the course of gardening or weeding (just try!), they can be spread about, each producing a new plant.

Lesser celandine leafs out early _ I've spotted some already in Philadelphia. When established, it will form a lush solid green carpet that blocks all light to small, later-emerging plants _ and chokes them out.

Do not let yourself be fooled that since they mature and "disappear" in June, the problem is manageable. They are prodigiously multiplying and will swamp you the next spring.

That's the bad news. Here's some more. According to Jil M. Swearingen of the National Park Service in Washington, there are no known biological controls. Unless you have only a very small infestation that makes weeding a (theoretical) possibility, you will have to use a ...