![]() ![]() Genera in the Asteraceae with the word thistle often used in their common names include: Cirsium horridulum found in southeast Louisiana. The tiny seeds are a favourite of goldfinches and some other small birds. Thistledown, a method of seed dispersal by wind. Taxonomy Carduus nutans in the early morning light. Ī thistle is the floral emblem of Scotland and Lorraine, as well as the emblem of the Encyclopædia Britannica. However, plants outside this tribe are sometimes called thistles.īiennial thistles are particularly noteworthy for their high wildlife value, producing such things as copious floral resources for pollinators, nourishing seeds for birds like the goldfinch, foliage for butterfly larvae, and down for the lining of birds' nests. The term thistle is sometimes taken to mean precisely those plants in the tribe Cardueae (synonym: Cynareae), especially the genera Carduus, Cirsium, and Onopordum. Typically, species adapted to dry environments have greater spininess. For example, Cirsium heterophyllum has minimal spininess while Cirsium spinosissimum is the opposite. The comparative amount of spininess varies dramatically by species. The typically feathery pappus of a ripe thistle flower is known as thistle-down. Typically, an involucre with a clasping shape similar to a cup or urn subtends each of a thistle's flower heads. These prickles are an adaptation that protects the plant from being eaten by herbivores. ![]() Prickles can also occur all over the plant – on the stem and on the flat parts of the leaves. Thistle is the common name of a group of flowering plants characterised by leaves with sharp prickles on the margins, mostly in the family Asteraceae. Milk thistle flowerhead Cirsium arizonicum, showing arachnoid cobwebbiness on stems and leaves, with ants attending aphids that might be taking advantage of the shelter. Not to be confused with Teasel, also a tall prickly plant.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |