Frond in the context of "Pinnate"

The Arecaceae (/ˌærəˈkeɪsi.iː, -ˌaɪ/) are a family of perennial, flowering plants in the monocot order Arecales. Their growth form can be climbers, shrubs, tree-like and stemless plants, all commonly known as palms. Those having a tree-like form are colloquially called palm trees. Currently, 181 genera with around 2,600 species are known, most of which are restricted to tropical and subtropical climates. Most palms are distinguished by their large, compound, evergreen leaves, known as fronds, arranged at the top of an unbranched stem, except for the Hyphaene genus, which has branched palms. However, palms exhibit an enormous diversity in physical characteristics and inhabit nearly every type of habitat within their range, from rainforests to deserts.

Palms are among the best known and most extensively cultivated plant families. They have been important to humans throughout much of history, especially in regions like the Middle East and North Africa. A wide range of common products and foods are derived from palms. In contemporary times, palms are also widely used in landscaping. In many historical cultures, because of their importance as food, palms were symbols for such ideas as victory, peace, and fertility.

The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (land plants with vascular tissues such as xylem and phloem) that reproduce via spores and have neither seeds nor flowers. They differ from non-vascular plants (mosses, hornworts and liverworts) by having specialized transport bundles that conduct water and nutrients from and to the roots, as well as life cycles in which the branched sporophyte is the dominant phase.

Ferns have complex leaves called megaphylls that are more complex than the microphylls of clubmosses. Most ferns are leptosporangiate ferns that produce coiled fiddleheads that uncoil and expand into fronds. The group includes about 10,560 known extant species. Ferns are defined here in the broad sense, being all of the Polypodiopsida, comprising both the leptosporangiate (Polypodiidae) and eusporangiate ferns, the latter group including horsetails, whisk ferns, marattioid ferns and ophioglossoid ferns.

Lemnoideae is a subfamily of flowering aquatic plants, known as duckweeds, water lentils, or water lenses. They float on or just beneath the surface of still or slow-moving bodies of fresh water and wetlands. Also known as bayroot, they arose from within the arum or aroid family (Araceae), so often are classified as the subfamily Lemnoideae within the family Araceae. Other classifications, particularly those created prior to the end of the twentieth century, place them as a separate family, Lemnaceae.

These plants have a simple structure, lacking an obvious stem or leaves. The greater part of each plant is a small organized "thallus" or "frond" structure only a few cells thick, often with air pockets (aerenchyma) that allow it to float on or just under the water surface. Depending on the species, each plant may have no root or may have one or more simple rootlets.

Tree ferns are arborescent (tree-like) ferns that grow with a trunk elevating the fronds above ground level, making them trees. Many extant tree ferns are members of the order Cyatheales, to which belong the families Cyatheaceae (scaly tree ferns), Dicksoniaceae, Metaxyaceae, and Cibotiaceae. It is estimated that Cyatheales originated in the early Jurassic, and is the third group of ferns known to have given rise to tree-like forms. The others are the extinct Tempskya of uncertain position, and Osmundales where the extinct Guaireaceae and some members of Osmundaceae also grew into trees. In addition there were the Psaroniaceae including Tietea in the Marattiales, which is the sister group to all the leptosporangiate ferns.

Other tree ferns include Leptopteris and Todea in the family Osmundaceae, which can achieve short trunks under a metre tall. Osmunda regalis is sometimes considered a tree fern. Fern species with short trunks in the genera Blechnum, Cystodium and Sadleria from the order Polypodiales and smaller members of Cyatheales like Calochlaena, Cnemedaria, Culcita, Lophosoria and Thyrsopteris are also considered tree ferns. The species Ctenitis sloanei (Florida tree fern) from Florida, Mexico, Bermuda and the Caribbean is sometimes called a tree fern. Like all ferns, tree ferns reproduce by means of spores formed on the undersides of the fronds.

Fiddleheads or fiddlehead greens are the furled fronds from a fledgling fern, harvested for use as a vegetable.

Left on the plant, each fiddlehead would unroll into a new frond (circinate vernation). As fiddleheads are harvested early in the season, before the frond has opened and reached its full height, they are cut fairly close to the ground.

Platycerium is a genus of about 18 fern species in the polypod family, Polypodiaceae. Ferns in this genus are widely known as staghorn or elkhorn ferns due to their uniquely shaped fronds. This genus is epiphytic and is native to tropical and temperate areas of South America, Africa, Southeast Asia, Australia, and New Guinea.