Mesophyte

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Mesophytes are terrestrial plants which are adapted to neither a particularly dry nor particularly wet environment. An example of a mesophytic habitat would be a rural temperate meadow, which might contain Goldenrod, Clover, Oxeye Daisy, and Rosa multiflora.

[edit] Properties

Mesophytes generally require a more or less continuous water supply, and have only basic features for water conservation, such as a cuticle and stomata. They usually have larger, thinner leaves compared to xerophytes, sometimes with a greater number of stomata on the undersides of leaves. Because of their lack of particular xeromorphic adaptations, when they are exposed to extreme conditions they lose water rapidly, and are not tolerant of drought.

For example, in hot weather they may overheat and suffer from temperature stress. They have no specific adaptations to overcome this, but, if there is enough water in the soil to allow this, they can increase their rate of transpiration by opening their stomata, thus meaning some heat is removed by the evaporating water. In dry weather they may suffer from water stress (losing more water via transpiration than can be gained from the soil). Again they have no specific adaptations to overcome this, and can only respond by closing their stomata to prevent further dehydration. Their cells are thus likely to lose turgidity. This may cause the plants cells to become plasmolysed, prompting wilting. This does actually have some benefits as it reduces the surface area of the leaf exposed to the atmosphere, which reduces transpiration. Prolonged periods of dehydration, however, can lead to permanent wilting, cell plasmolysis, and subsequent death.