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A xerophyte (from Ancient Greek ξηρός (xērós) 'dry' and φυτόν (phutón) 'plant') is a species of plant that has adaptations to survive in an environment with little liquid water. Examples of xerophytes include cacti, pineapple and some gymnosperm plants.
Marram grass has a rolled leaf that creates a localized environment of water vapour concentration within the leaf and helps to prevent water loss. The stomata sit in small pits within the curls of the structure, which makes them less likely to open and lose water. The folded leaves have hairs on the inside to slow or stop air movement, much ...
The young larvae eat the buds and either destroy developing leaves, or cause leaves to develop with many holes in them. This can severely stress the tree's food reserves, and the older larvae can eat nearly all the remaining leaves, defoliating them. [7] When trees are defoliated two or more years in a row, "extensive tree mortality" can result ...
The leaves have deeply furrowed upper surfaces and smooth undersides, and grow 1 to 3 feet (0.3 to 0.9 m) tall. The plant's inflorescence is a spike-like panicle that can reach 10 inches (25 cm) long; The spikelet is single-flowered, awnless. [4] The seed head appears in late July or August. [5]
Not all xerophytes are succulents, since there are other ways of adapting to a shortage of water, e.g., by developing small leaves which may roll up or having leathery rather than succulent leaves. [8] Nor are all succulents xerophytes, as plants such as Crassula helmsii are both succulent and aquatic. [9] The center rosette of Aloe polyphylla
When the seeds are about ripe, the fruit remain attached to the peduncles, but the stem of the umbel detaches, permitting the globes to roll about in the wind. The light, open, globular structures form very effective tumbleweed diaspores, dropping their seeds usually within a few days as the follicles fail under the wear of rolling.
Raunkiær's life-form scheme has subsequently been revised and modified by various authors, [6] [7] [8] but the main structure has survived. Raunkiær's life-form system may be useful in researching the transformations of biotas and the genesis of some groups of phytophagous animals.
The larvae feed on plants (often conifers), using silk to build webs or tents, or to roll leaves into tubes in which they feed, thus earning them the common names leaf-rolling sawflies or web-spinning sawflies. Some species are gregarious and the larvae live in large groups. Fossils of Pamphiliidae have been dated to the Jurassic period. [1]