This is by far the commonest Weissia you are likely to encounter, and it grows in a surprisingly wide range of habitats and on different soil types. Being a dehiscent Weissia species, it is rather frustrating for bryologists in the winter. Although the seta lengthens and capsules are often present by November, it is often not until the following March or April that lids finally drop.
Unfortunately, the peristome is an essential diagnostic character and plants cannot be identified with certainty until it is visible. The peristome is long-lived, but variable. Some plants have obvious peristome teeth, whilst in others they are rudimentary and can be easily missed with a hand-lens.
- Weissia controversa var. controversa – the nominate variety and by far the commonest, with extremely catholic taste in habitats;
- Weissia controversa var. crispata – quite a distinctive variety, with a stout reddish nerve and leaves often tinged brown. Of the three varieties, this is the most strongly calcicolous and is indicative of unimproved chalk and limestone grassland. Weissia brachycarpa also has quite a stout reddish nerve but is easily distinguished from var. crispata once the lids have fallen by its small mouth and epiphragm;
- Weissia controversa var. densifolia – var. controversa can also be common on the metalliferous soils where this rare variety is found, but var. densifolia is generally a taller plant with a shorter seta, so it is reasonably distinctive.