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SUBORDINATE VEGETATION. 
Suitable mixing of the large-growing species and genera may have a beneficial 
influence upon the health and vigour ot the trees, (c) An exuberant and mingled 
undergi owth will contribute to the wellbeing of the forest in a still greater degree, 
and may even entirely obviate the need for mixing the timber yielders. 
The choice of large-growing trees for mixing in any locality will be made easy 
by information given under the specific descriptions. The formation of an 
undergrowth will require intelligent direction and a little persistent effort. Our 
indigenous flora can give us pittosporums, coprosmas, and other shade bearing 
plants. Australian botanists will be able to name for us the most suitable of the 
acacias. Iree lucerne is already with us and can be propagated from locally grown 
seed. When seed of these various plants has been obtained, broadcast sowing will 
be the nearest approach to nature’s method for its distribution. These plants 
will cause no trouble in the felling of the trees. In the restocking of the ground 
they will serve as nurses for the more tender of the new tree plants. 
The theory here propounded of a mixed vegetation over the Eucalyptus forest 
floor may be challenged. In New South Wales, while forestry was under the 
eminently able direction of Mr. R. Dalrymple Hay, it was laid down as a first 
principle that the forest floor should be cleared of all debris and growths except 
seedlings and coppice shoots of the approved timber yielders. To form a judgment 
we must compare conditions. In N.S.W. the task of the forester is mainly that of 
reducing to order natural forests that have in many instances been damaged by 
the inroads of timber getters or by fire. Instead of clear felling and complete 
restocking, there is imposed the necessity for following up with perpetual 
regeneration and continuous selective felling. In New Zealand we are starting 
entirely new plantations and may treat them in any way that shall seem most 
convenient. We have also to consider the cooler and damper conditions under 
which many of our plantations will grow. 
THE PERIL OF BARE EARTH. 
To the writer of this book the question of undergrowth in the forest seems 
only like one aspect of a very much greater biological and economic problem. 
Geologists tell us that the land surfaces of the earth were formerly much higher 
and much more extended than at present. \ alleys and terraces and contours 
everywhere bear witness to ancient erosion. The tonnage of soil and silt cariied 
down from continents and islands to the ocean bed in any thousand years admits 
no calculation or estimate. And nature knows only one way to arrest erosion. 
That is to cover the surface of the land with vegetation. Naked eaith must yield 
to the bite of frost, the lashing of wind, and the swift rushing of water. Only 
vegetation can protect and save it. All plants contribute to this seivice. Mosses 
and ferns and herbs and grasses and trees all enrich and consei\e the soil suiface 
of the earth. A. great and complex forest is nature s supieme achievement in 
combating the eroding forces and in storing fertility. 
To man was committed the custody of this protective earth covering. The 
story of his trust is long and sad. In what we call the ancient world the death of 
forests hy the hand of man was followed by the death of cities and by the desolation 
of wide landscapes. We of to-day who count ourselves scientific are only half wise. 
