This section is from the book "A Manual Of Weeds", by Ada E. Georgia. Also available from Amazon: A Manual Of Weeds.
Native. Perennial. Propagates by seeds and by rootstocks. Time of bloom: June to July. Seed-time: July to August. Range: Throughout North America. Habitat: Marshes, wet meadows, and pastures; muck farms. In the South, a pest in rice fields.
In any place where the soil is constantly moist some variety of this rush is likely to be found, and it holds its ground most sturdily. It grows in dense tufts or tussocks from stout branching root-stocks, the leafless stems one to three feet tall, erect but very soft and pliant, round, green, pithy, and about a twelfth of an inch in diameter. Flowers very numerous in dense, spreading cymose clusters which seem to burst from the sides of the stems, the long subtending bracts appearing like continued stems; each individual flower has also just below it a small, ovate, pointed bract; perianth six-pointed, green at first, but soon turning brown; stamens three, with anthers and filaments about the same length; style very short. Capsules bluntly oblong, three-celled, filled with fine brown seed, which is widely sown by the wind. (Fig. 40.)
Fig. 40.-Common or Soft Rush (Jun-cus effusus, var. Pylaei). X 1/4.
Drainage of the ground, and a season or two of thorough cultivation, are necessary in order to destroy the system of branching rootstocks. For small areas they may be grubbed out.