BBC Gardeners' World

Leaf

The photosynthetic organ of a plant, which is attached to the stem or axis. It performs the functions of transpiration and carbon assimilation, as well as food manufacture.

Leaf blade

See Blade.

Leaf curl

A fungal disease of peach, almond and nectarine trees, which causes an increase in cell growth, resulting in thick, puckered and curled leaves. These will then change colour from green to yellow and dark red.

Leaf cutter

Of the bee family, similar to the honey bee. Distinguished by the orange hairs on its underside and the powerful jaws with which it shears off pieces of leaf. May cause damage to the leaves of roses, laburnums, lilacs, etc, during the egg-laying season, which runs from June to July.

Leaf miner

A grub, the larva of small flies and some moths, which tunnels into the leaves of plants. Damage to the leaves takes the form of a pattern of semi-transparent lines or pale, blistered patches.

Leaf-mould

Composted fallen leaves, or the detritus of partially decayed leaves found under trees.

Leaf spot

Symptom of a variety of viral diseases that attack the leaves of many plants, but particularly roses. The spots can be of various colours. Afflicted plants will need to be treated with a fungicide.

Leaflet

A new or young leaf.

Leatherjacket

A maggot, the larva of the cranefly or daddy-longlegs, which attacks the roots of many plants, including flowers, vegetables and pot plants. May also attack lawns, causing dead patches of grass to appear.

Legume

1) A pod. A dry open fruit containing one or more seeds, such as the pea or bean.

2) A member of the family Leguminosae.