TREES FOR WATER CATCHMENT AREAS 141 
such are invariably attacked by the fungus. It is advisable 
also to raise larch seedlings in the home nursery; and thus 
avoid the chance of importing diseased plants from a distance. 
It is probable also that the choice of seed is of great 
importance, as bad seed produces feeble seedlings, which 
readily succumb to disease when planted out. The question 
of home-grown versus Swiss seed is not decided. The 
foreign seed shows, as a rule, higher germinating power, but 
this is probably due to more care having been taken in 
the gathering and cleaning of the seed. Scott-Elliot found 
Scottish seed to be lighter and smaller on an average than 
Swiss seed. If seed were gathered from the best Scottish 
trees, it might be as good or even surpass in quality the 
Swiss seed. One thing can be done, namely, to discard and 
burn all feeble seedlings, and only plant out strong, 
vigorous, and well-rooted plants. 
Selected plots of larch (Fig. 25) often show very heavy 
yields of timber. In the Galtee Mountains, Ireland, plots 
measured by Mr. Waddingham gave the following results 
(quarter-girth measurement) : 
S Aer Volume Average Annual 
“in Feet. Sage.» | Peso, |< eerie, 
600 34 3180 94 
700 44 3920 89 
480 53 4588 86 
400 53 4043 76 
400 55 4855 88 
1000 63 3861 61 
In the Forest of Dean, on good sandy loam at 700 feet, 
three plots of one acre each, 65 years old, gave yields 
of 4014, 4081, and 4893 cubic feet, being 61, 63, and 
76 cubic feet of annual increment per acre. At Madresfield 
a plantation 21 years old measured 2408 cubic feet, or an 
annual increment of 115 cubic feet per acre. 
A large grove of 24 acres at Walcot, Shropshire, which, 
judging from the rings, was 124 years old, had 86 
