191 1.] The Use of Manures in Forestry. 
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one of the following ways : — (1) planting of leguminosse, 
especially lupins and acacias, on sandy soil, and trefoil and 
grey alder on chalky soils ; (2) dressings with turf and other 
substances containing humus ; (3) covering the soil with lupin- 
haulm, potato tops, straw, leaves, and small twigs ; and 
(4) interplanting with a species having a heavy leaf fall, such 
as Pinus rigida and Pinus montana. Lupins, which in many 
cases have proved of great value, can be used in one of two 
forms, either as a crop before the trees are planted, or between 
the lines of trees. For the first purpose, the yellow lupin, 
and for the second the blue lupin, is best suited. When the 
whole area is cropped before planting trees, a dressing of 
about si cwt. to 6J cwt. of basic slag and if cwt. to .3J cwt. 
of kainit per acre should be used. In addition inoculation 
with nitragin may be recommended, although lupins gener- 
ally grow well, even on poor heath lands, and on soils which 
have not carried a leguminous crop. If the lupins develop 
poorly in the first year, they must be sown again the second 
year. It is necessary in every case to get a good crop of 
lupins before planting. The cost of raising a crop of lupins 
is said to be about £1 12s. per acre in Germany, but in 
Belgium an intermediate crop of rye or oats is taken in 
order to reduce the cost. The fact that phosphoric acid and 
nitrogen are removed by rye and oats is not sufficient to 
prevent an appreciable enrichment of the soil in these sub- 
stances. In Germany, experiments are being made to test 
the effect of substituting potatoes for rye as an intermediate 
crop. This method has the advantage that the soil is worked 
up in digging the potatoes, and the tops are left on the 
ground. 
A cheap system is to interplant with blue lupins. By this 
method the area is ploughed up in the late autumn in the 
usual way, and during the winter manured in the drills with 
basic slag and kainit. The pines are planted the next spring. 
In this way only 25 to 30 per cent, of the area is manured. 
In favourable seasons excellent results are obtained. On 
chalky heathland, the place of the lupin can best be taken by 
Trifolium hybridum, grown between the forest trees. 
There are also a number of trees which possess the property 
of utilising the free nitrogen of the air, and making it avail- 
