108 FORESTS, WOODS, AND TREES 
Ireland, extensive hill plantations and shelter belts might 
be made on the co-operative system if State aid in the shape 
of loans for planting were available. 
The recognition of the hill-pasture zone is easy if it is 
understood to include all the ground above the enclosed farm 
land and below the heather moorland. Its altitude is 
variable, ranging, for example, in the Dublin Mountains 
between 900 and 1250 feet and in the Northern Pennines 
between 1000 and 1250 feet. It is also very variable in 
composition, including woodland, scrub, grassland, brakes of 
bracken fern, and thickets of small whin (Ulex gallii) on 
siliceous soils. In the Pennines the natural wood is mainly 
oak or birch, the former small and scrubby above 1000 feet, 
the latter ascending to 1250 feet. The grassland consists 
mainly of mat-grass (WMardus stricta) and silver hair grass 
(Deschampsia flecwosa) on the drier soils, with sheep’s fescue 
(Festuca ovina) at the lower levels, while the wetter ground 
is dominated by purple moor-grass (Molinia caerulea). 
Bracken occurs over large areas in places, and its present 
upper altitude line corresponds very closely with the limit 
reached by the pre-existing forest. In fact, wherever 
bracken and small whin are present they are a sure sign 
that plantations may be tried with confidence. Dr. W. G. 
Smith says: “Bracken is an indication of a soil at least 
six or nine inches deep, moist yet well drained, and not peat, 
because only in these conditions can the underground stems 
of this fern survive; the conditions are therefore suitable 
for afforestation.” The small whin occurs only in patches 
in the Pennines, but is very abundant on the Malvern Hills 
and the Dublin Mountains. On limestone soils the zone of 
hill pasture has a different composition, the characteristic 
woods being ash, birch, and wych elm, while the grassland 
is a short grassy turf, largely composed of roots of sheep’s 
fescue. The characteristic grasses of non-limestone soil, 
Nardus, Deschampsia, and Molinia, are totally absent. 
Bracken, whin, and rushes, so common on siliceous soils, 
are of very rare occurrence, and perhaps are confined to 
leached soils or soils mixed with non-calcareous material. 
