In recent years, planting of alder has increased dramatically. Accurate information on area planted is difficult to source because the species usually features in the category 'other broadleaves' which now amount to around 20% of all planting.

In addition to alder, species featured under 'other broadleaves' include birch and, to a much lesser extent, sweet chestnut, cherry, lime and maple.

Data from nurseries would suggest that alder now forms more than half of 'other broadleaves'. It has more than doubled oak planting and now equals ash.

Alder has gained in popularity for a number of reasons. It is native, so qualifies as an approved species in the Native Woodland Scheme.

It will adapt to a far greater range of soil types and site conditions than oak and has replaced non-native but naturalised broadleaves such as sycamore and beech, species that are more vulnerable to grey squirrel damage.

Common or black alder (Alnus glutinosa) appears as Class 2 (commoner of the wood) in the Old Irish tree-list. Places such as Ferns or Fearna, Co Wexford, Glenfarne or Gleann-fearna, Co Leitrim are derived from its Irish name - fearno¨g.

However, the fact that alder qualifies for grant aid under the Native Woodland Scheme is an insufficient reason on its own to plant it in such large numbers. Alder, like many species, has its strengths and weaknesses as a forest tree.

It is a tree for the wetlands, where its ability to grow well, even on poorly drained sites, is regarded as its main strength.

It will out-perform most broadleaves on soils of moderate fertility but grows best in sheltered sites with moist fertile soils.

As explained in the excellent COFORD publication A Guide to Forest Tree Species Selection and Silviculture in Ireland by Horgan et al, it is a nitrogen-fixing tree: ''Nodules attached to its roots, containing bacteria (Frankie species), enable the tree to make direct use of atmospheric nitrogen. It is useful as a nurse for oak on heavy soils and for ash, where its role in fixing nitrogen is often beneficial.''

It is reasonably easy to establish which is why stocking rates (number of plants per hectare) have always been less than species such as oak and beech.

Alder stocking have been further reduced since January this year from 3,300 to 2,500/ha.

Compared with most broadleaves, it is a relatively short-lived species. Although there are some examples of long-lived alder in Ireland, these are exceptions.

It establishes easily and will achieve heights of up to 13m by year 15, but overall production over its rotation is not exceptionally high. According to the COFORD guide, productivity is unlikely to exceed 8m3 per annum and ''as it is such a short-lived species, it seldom grows to large sizes''. The guide maintains that typical rotation lengths are between 30 and 50 years. Alder seems to be resistant to serious pest and disease damage, although it occasionally suffers from Phytophthora cambivora root rot. It produces an attractive timber and the COFORD guide maintains that ''current demand for top quality logs greatly [exceeds] supply''.

Because of its increasing popularity, COFORD - the Programme of Competitive Forest Research and Development - has been examining the current supply and demand for seed and plants.

A working group has initiated a research project to develop a sustainable supply of new material for tree breeding and ultimately tree improvement.

So does alder deserve its new-found status as the most popular native species alongside ash in recent annual afforestation programmes?

Alder has a role to play, especially in the Native Woodland Scheme where soil and site conditions preclude oak and ash and the native conifer Scots pine.

On poor sites it is a safe bet. It provides few headaches at the establishment phase as it grows quickly, so vegetation control is minimised. However, if timber production is a major objective, tried and trusted coniferous species such as Sitka and Norway spruce on poor sites are far more attractive options.

These species provide superior yields and ready markets over similar rotations. Ash is a much better choice on moist reasonably fertile sheltered sites.

Despite its ability to produce excellent timber, the marketability of alder alongside other native timbers, in terms of future economies of scale and processing capability, are issues that have not been addressed satisfactorily in Ireland.

The forestry sector needs accurate data on the actual area being planted with alder to assess its potential.

However, if alder afforestation has reached 25% of broadleaf planting or 10% of all planting, as the best evidence seems to suggest, then it has acquired a status as a major tree species in Irish forestry, which it scarcely deserves.