PAPPUS - INFO
A pappus is a large mass of (usually white) hairs (or hairs atopped by a ring of finer hairs like an umbrella or parachute) that carry the seeds away by wind.
Some pappi are made of scales or are bristly and heavy, and do not blow away by wind, but instead just drop to the ground close to the plant which bears them, or are caught in animal fur to be transferred a distance from the plant. If this is the case, then it will say so by the words such as 'Pappus: short, bristly, not borne by wind'. Examples are the short bristly pappus on Beggarticks which has barbs to engage with animal fur or human clothing in order to be carried away. Many plants belonging to the Daisy & Dandelion Family (Asteraceae) possess pappi but by no means all.
Many pappi are just 'simple' being a bunch of hairs attached to a seed at the bottom. Others one single thicker hair attached to the seed, but the other end branches out like the skeleton of an umbrella (a 'compound' pappus). The Author believes that the official term is 'plume thistle' (which could be misleading). The ribs of the 'umbrella' may also either be un-branched, or feather-branched (a sort of compounded compound) for even greater wind-resistance, which helps carry heavier seeds by wind-power.
This month by month chart shows if the plant has a pappus, and if so, in which months the pappus is found. It should be noted, that in many instances, your Author has had to guess when the pappus opens and stays on the plant until finally being blown away, for this information is not generally reported.
The SEARCH page enables you to search for the presence of a pappus (using pappus?possible, or ticking the check-box). Of much less use, you can also search for if the Author thinks a pappus may be found in any particular month (using pappus?aug, for instance - but there is no check-box for searching by month, since it is less than useful; your Author has had to guess most of the data for the months when the pappus may be on show. And remember that the purpose of a pappus is to be blown away by the wind, and if it has been very windy and if they are ripe for departing from the parent plant, there will be fewer or none left.
Cotton-grasses such as Hare-'s-tail Cotton-grass, Willowherbs and some Willows are also plants possessing pappi; hairs attached to seeds for the main purpose of being borne by the wind. Willowherbs have the pappus enclosed within a long square-section cylinder which splits like a banana when ripe displaying the seeds with their long hairy parachutes.