38 PASTURE STUDIES: SOME RESULTS. 
The sudden increase of the plant on Area 2 at 64 years was 
undoubtedly due to the application of Basic Slag (16), (13), but 
the effect of the Slag was not very lasting here, as at 84 years the 
plant was almost equally well developed on Area 3, which had not 
been slagged. On this latter area, however, the relatively high 
development of the plant may be due to the thorough cleaning of 
the land, but at 9} years it was only slightly more abundant on 
Area 2 than on Area 4 at 134 years, which had not been slagged, 
and on which the plant had not been sown, so that apparently the 
effect of the Slag on this plant was exhausted in three years. 
The plant was not recorded by either method of examination 
on Area 8, but it is known that weak plants were to be found in 
the former grass heath of Area 6. ‘‘ White or Dutch” seed was 
sown on Areas 6 and 7, but the plant had a P.c. fr. of only 8-4 on 
the former area at 44 years. Following a dressing of Basic Slag, 
however, it increased to 27-3 in the following year, and at 64 
years it still had a P.c., fr. 24-7. Its decrease was then as rapid as 
its previous increase, probably to a great extent owing to the 
exhaustion of the effect of the Slag, but partly also probably to the 
effect of the drought! The same quantity of seed was sown on 
Area 7, but this area was not examied by the P.c. fr. at 44 years. 
The Sp. fr. of the plant at that date was relatively low (sp. fr. = 60). 
and its P.c. fr. at 54 years, following a dressing of Basic Slag as on 
Area 6, at the corresponding date, was very much lower than on 
the latter area, so that here again apparently the effect of the 
seeds-mixture as a whole is seen. 
From these results it is seen that the amount of ‘“ White or 
Dutch” seed sown may bear no relationship to the development 
of the plant at 54 years, and that at 134 years at most, its inclusion 
has no apparent effect on some soils. Its development in the 
pasture appears to be very largely a matter of cultivation, manur- 
ing and treatment, but other results (9) show that “ Wild White 
Clover” seed may hasten the development of the plant very 
considerably in a pasture. 
1Jt has been found elsewhere that heavy grazing with sheep has no such 
effect on the plant. Cf. Stapledon on the effect of drought (15). 
