36 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 



with Marram grass {Fsamma arenarid) and some Lyme grass 

 {Elymus arenaria)^ which have bound the sands well. The 

 Corsican pine was planted some 22 years ago along with several 

 hardwoods — (principally birch) — in alternating rows 3 feet apart, 

 and 3 feet between each plant. The hardwoods, however, have 

 now been totally suppressed. The Scots pine was planted pure, 

 at 3 feet apart, 19 years ago. These trees, when planted, 

 had no shelter of any kind ; the sand dunes at this particular 

 point being very low, and therefore there is nothing to break the 

 force of the wind which sweeps off the sea. The plantation, 

 however, is flourishing well in the pure sand, the number of 

 trees per acre being, approximately, 2300 Scots pine and 1896 

 Corsican pine. The canopy is complete, and the stems very 

 healthy. 



Further inland, at a distance of approximately one mile, there 

 are several small plantations, and these consist chiefly of 

 Corsican pine and Scots pine, which were planted some 40-50 

 years ago for the purpose of providing shelter to agricultural 

 crops against the cold, dry winds. These trees grew fairly well, 

 and on viewing the plantations, it can be seen that the Corsican 

 pine has surpassed its neighbour — the Scots — both in height 

 and volume of timber. Along the coast and landward of the 

 small plantation from which specimens were selected the area, 

 which stretches for several miles, is at present totally unpro- 

 ductive and quite unfit for agricultural purposes. But, as can be 

 seen from the results of the stem analysis investigation of both 

 Corsican and Scots pine given below, it will be possible in 

 time — it is to be hoped — to grow timber to a profitable size, 

 which will ultimately bring in a good return. 



Stem Analysis.— By this is meant the investigation of the 

 process of increment throughout the life of a tree. In this case, 

 two average stems of each species— Corsican and Scots pine, both 

 growing in the same compartment — were felled ; each divided 

 into a suitable number of cross-sections; the number of con- 

 centric rings was then counted ; and the diameter at the several 

 ages measured. These measurements were plotted. The heights 

 from the ground of the several cross-sections were marked on 

 a vertical line representing the axis of the stems, also the 

 heights the trees had attained at successive periods of their 

 lives (Plate IV. Figs, i and 2). Then the radii of the cross- 

 sections were marked on horizontal lines, and the points thus 



