In the spirit of the season, the following trees of Ireland have been grouped together, for the supernatural or superstitious aspects of the names, however tenuous the connection.

Wych elm
Ulmus glabra
Leamhán sléibhe
Native (D) (3 4)

The wych elm (or Irish elm) is a large tree with spreading branches. It has been commonly planted in most areas but is rare as a native, except in remoter parts of the north-west and west where pockets of trees unaffected by disease still occur.Leaves are large (ten to twelve centimetres long), undivided and roughly toothed along their edge, broadly oval and pointed with very asymmetrical bases and rough upper surfaces.

Broom
Cytisus scoparius
Giolcach sléiobhe
Native (E) (5-6)

The broom grows as a shrub up to about two metres tall, has large, bright, lemon-yellow pea-like flowers and green branchlets. Its leaves are divided into three oval leaflets and arranged alternately on the five-angled shoots. However, the leaves are soon lost as the branchlets mature. Its flowers are about two centimetres long and its seed capsules are black, with brown hairs along the edges, and 2.5 to four centimetres in length.

It occurs in dry heathy places, open woods, on dry banks and roadsides and is widespread throughout Ireland but rarely common. It occurs through Europe, growing on light lime-free soils only. The broom obtained its name from the former use of its branches for making brushes . A rare prostrate form with silky leaves is found on a few coastal cliffs and is worth looking out for. A wide range of European species and cultivated varieties are grown in Irish gardens.

Hazel
Corylus avellatta
Coll
Native (D) (2-3)

One of the most widespread woodland plants in Ireland is the hazel. It is typically a bushy multi-stemmed shrub between one to six metres tall in oak and ash woods but may rarely become a small tree. It was widely used for coppice to provide slender sticks for many purposes: fences, fuel, hurdles, hoops for barrels (before these were replaced by metal bands). Their nuts are excellent to eat, although there is no commercial production of them in Ireland that I know of. The hazel has always been a special tree in Ireland, used to ward off spil spirits and fairies. A hazelnut carried in the pocket was said to keep away lumbago and rheumatism.

Hazel leaves are alternately arranged, rather wrinkled, about ten centimetres long, oval to almost round with a pointed tip and jaggedly double-toothed edge, light green and softly hairy. The twigs are also hairy and covered with reddish, slightly sticky (glandular) hairs. Male catkins are about eight centimetres long, bright yellow and hanging down like lambs' tails but in clusters of up to four. The female catkins are much smaller, like tiny buds five millimetres long from which the bright red styles protrude. The fruits ripen as brown hard-shelled nuts about 1.5 centimetres long contained with a shaggy leaf-like cup.

Hazel occurs commonly throughout Ireland in hedgerows and woodlands and sometimes as dense thickets where it can be the dominant species, such as in the hazel scrubs of the Burren in Co. Clare.