Fall Leaf

Autumn

Autumn, also known as fall in North American English, is one of the four temperate seasons on Earth. Outside the tropics, autumn marks the transition from summer to winter, beginning in September or March. Autumn is the season when the duration of daytime becomes noticeably shorter and the temperature cools considerably. Day length decreases and night length increases as the season progresses until the winter solstice in December and June. One of its main features in temperate climates is the striking change in colour of the leaves of deciduous trees as they prepare to shed.

Leaf

A leaf is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, flower, and fruit collectively form the shoot system. In most leaves, the primary photosynthetic tissue is the palisade mesophyll and is located on the upper side of the blade or lamina of the leaf, but in some species, including the mature foliage of Eucalyptus, palisade mesophyll is present on both sides and the leaves are said to be isobilateral. The leaf is an integral part of the stem system, and most leaves are flattened and have distinct upper (adaxial) and lower (abaxial) surfaces that differ in color, hairiness, the number of stomata, the amount and structure of epicuticular wax, and other features. Leaves are mostly green in color due to the presence of a compound called chlorophyll, which is essential for photosynthesis as it absorbs light energy from the Sun. A leaf with lighter-colored or white patches or edges is called a variegated leaf.

fall

Verb

1. To be moved downwards.

Noun

1. The act of moving to a lower position under the effect of gravity.
2. A reduction in quantity, pitch, etc.

leaf

Noun

1. The usually green and flat organ that represents the most prominent feature of most vegetative plants.
2. A foliage leaf or any of the many and often considerably different structures it can specialise into.

Verb

1. To produce leaves; put forth foliage.
2. To divide (a vegetable) into separate leaves.