The beautiful Dicranum scoparium moss is unmistakable in its windswept appearance. The white or brown fuzzy tomentum obscuring the stem will help to secure its identity if one is in doubt. While looking at the tomentum of a female gametophyte with a sporophyte, you might notice something peculiar….
Roughly 20% of Dicranum species are pseudomonoicous whereby the male
plant is tiny and epiphytic on the rhizoids of the female plant.
You might notice a little tiny male plant hanging out on the side of the stem. Roughly 20% of Dicranum species are pseudomonoicous whereby the male plant is tiny and epiphytic on the rhizoids of the female plant. This male dwarfism is also called nannandry. What’s more, Dicranum scoparium takes it a bit further by also having the ability to have full sized male plants. Research suggests that this is an environmentally controlled situation.
Above left: white tomentum on the stem; Above Middle: A population with sporophytes…let’s see if any of them have a tiny male attached!; Above right: A female gametophyte with tiny epiphytic male plants. See close up below.
The blue arrows are pointing towards male plants on this female gametophyte. The pink arrows are pointing towards mature sporophytes.
Other known Dicranum species in Missouri that are pseudomonoicous are D. condensatum, D. polysetum, and D. spurium. Next time you see one with a sporophyte, check out the stems to see if you can find a little guy hanging out!
Do you need a moss field guide to Missouri and the Midwest? Check out my book here. https://mossesofmissouri.com/2025/04/29/the-art-of-connection/
Mosses of Missouri and Beyond 
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