PROTECTION OF DUNES. 598 
and the observations of Andresen in Jutland carry the number 
of these vegetables up to two hundred and thirty-four. 
Some of these plants, especially the Arwndo arenaria or 
arenosa, or Psamma or Psammophila arenaria—Klittetag, or 
Hjelme in Danish, helm in Dutch, Diinenhalm, Sandschilf, 
or Hiigelrohr in German, gourbet in French, and marram in 
English—are exclusively confined to sandy soils, and thrive well 
only in a saline atmosphere.* The arundo grows to the height 
of about twenty-four inches, but sends its strong roots with 
their many rootlets to a distance of forty or fifty feet. It has 
the peculiar property of flourishing best in the loosest soil, and 
a sand-shower seems to refresh it as the rain revives the thirsty 
plants of the common earth. Its roots bind together the dunes, 
and its leaves protect their surface. When the sand ceases 
to drift, the arundo dies, its decaying roots fertilizing the sand, 
and the decomposition of its leaves forming a layer of vege- 
table earth over it. Then follows a succession of other plants 
which gradually fit the sand-hills by growth and decay, for 
forest planting, for pasturage, and sometimes for ordinary agri- 
cultural use. 
But the protection and gradual transformation of the dunes 
is not the only service rendered by this valuable plant. Its 
leaves are nutritious food for sheep and cattle, its seeds for 
poultry ; + cordage and netting twine are manufactured from 
its fibres, it makes a good material for thatching, and its dried 
roots furnish excellent fuel. These useful qualities, unfortu- 
nately, are too often prejudicial to its growth. The peasants 
feed it down with their cattle, cut it for rope-making, or dig it 
up for fuel, and it has been found necessary to resort to severe 
legislation to prevent them from bringing ruin upon themselves 
* There is some confusion in the popular use of these names, and in the 
scientific designations of sand-plants, and they are possibly applied to different 
plants in different places. Some writers style the gourbet Calamagrostis ere- 
naria, and distinguish it from the Danish Klittetag or Hjelme. 
+ Bread, not indeed very palatable, has been made of the seeds of the 
arundo, but the quantity which can be gathered is not sufficient to form an 
important economical resource.—ANDRESEN, Om Klitformationen, p. 160. 
08 
