CONTRIBUTIONS FROM THE WISLEY LABORATORY. II 7 



manure at the rate of 20 tons to the acre and with sulphate of ammonia 

 and superphosphate, after which a crop of early potatos was taken. 

 In August mustard was sown and ploughed in in November. The 

 trees were planted ten feet apart each way in January 1912 in open 

 weather. They were as nearly as possible of a size at planting time 

 and were of the same age. There were five varieties and five trees 

 of each variety. After planting, turf was laid up to the stems of 

 two trees of each variety and so as to leave a circle of three feet of 

 bare soil about the stems of two others, the fifth tree in each case 

 being cultivated all round. Pigure 14 on page 116 shows the 

 arrangement of the plot. 



The soil about the trees in the 1st row has been continuously 

 cultivated ; the soil in the space about the trees in rows 2 and 3 has 

 been kept bare of grass and stirred at intervals. The grass has been 

 cut two or three times a year but not removed, so the soil has lost 

 nothing from the presence of the grass (except water and oxygen 

 taken by the grass roots). 



The tables on pages 118 and 119 show the amount of growth made 

 by the trees in each year since planting ; the first showing the total 

 length of the new shoots made each year, the second the diameter of 

 the stem at nine inches from the ground in each year (except 1917). 



It will be seen that the growth of the tiees with the space about 

 them has been consistently greater than that of the trees with grass 

 up to their stems * (indeed, in some cases the latter are smaller than 

 when they were planted — they have never made up the length of 

 stems removed when they were first pruned, and in one case the 

 tree is dead), and this has been exceeded in a marked measure by 

 the trees in cultivated ground, in every case in every year. The 

 crops borne tell the same tale, as the following table shows : 



Total Number of Fruits produced by each Tree 1912-1919. 



- 





In Grass. 



In 3 feet clear space. 



In cultivated 

 land. 





1 





2 



1 



2 



1 



Ribston Pippin . 

 Manks Codlin . 

 Newton Wonder 

 Beauty of Bath 

 Emperor Alexander . 



0 

 0 

 0 

 0 

 2 



O 



5 

 0 

 0 

 16 



O 

 6 

 0 



14 



66 



27 

 8 

 0 

 5 



28 



192 



297 



77 

 21 

 224 



As usual, there is a marked contrast between the colour of the 

 foliage of the trees in the cultivated ground and those with grass about 

 them, the latter being much more yellow in tinge ; the few fruits 

 produced on the latter trees have been on the whole smaller than 

 the many on the former. 



* One tree of Manks Codlin in grass is an exception to this, for it has ex- 

 ceeded in some cases since 1914 the growth of either of the trees with the 

 cultivated space around them. 



