538 Summary of Agricultural Experiments, [oct., 



golds are only suitable for a better class soil than can be found in the 

 district. The soil of the College Farm, however, is by no means above the 

 average. 



Varieties of Mangolds (Essex Education Com., Field Expts., 1906). — 

 Three varieties were grown at three centres, and gave the following average 

 yields : — Yellow Globe, 27 tons ; Long Red, 25^ tons ; and Golden Tankard, 

 22| tons. 



The quality, whether valued on dry matter or sugar content, was 

 decidedly poor ; but this must be attributed to the season. Calculating the 

 dry matter and sugar per acre, the average yield of Long Red was 3 tons 

 dry matter and i ton 8 cwts. sugar ; of Yellow Globe, 2 tons 10 cwts. dry 

 matter and 1 ton 3 cwts. sugar ; and of Golden Tankard, 2 tons 10 cwts. dry 

 matter and 1 ton 2 cwts. sugar. It will be noticed that Yellow Globe, i 1 

 virtue of its superior yield, a little more than makes up for its deficiency i 1 

 quality with respect to Golden Tankard. 



Composition of Root Crops {Cambridge Univ. Dept. of Agric, Guide to 

 Expts., 1907). — Experiments are in progress with a view to the improvement 

 of root crops, and the results are given of (1) the composition and weight of 

 196 individual Golden Globe mangolds ; (2) the average yield and composi- 

 tion of some leading types of mangolds grown on the University Farm in 

 the five years 1902- 1906 ; (3) composition of types of mangolds grown in 

 1902, 1903, and 1904 at four stations in Norfolk ; (4) composition of three 

 leading types of mangolds grown in 1902-1905 at various centres ; (5) com- 

 position of French and German mangolds grown at the University Farm in 

 1905 ; (6) effect of manures on the composition of mangolds in 1905 ; 

 (7) percentage composition of four varieties of swedes grown at various 

 centres in 1903 and 1904 ; (8) composition of two varieties of swedes grown 

 at the University Farm from seed procured from various parts of England ; 

 (9) composition of white turnips and kohl-rabi grown in 1904. 



The method adopted with a view to the improvement of mangolds 

 involves two stages. First, all the best-known varieties are grown, and the 

 yield per acre ascertained ; samples are then taken and analysed with a view 

 of determining which variety is the most profitable — i.e., gives the most food 

 per acre. So far, Long Red has come to the front on soils which are dee 

 and good enough to grow it to perfection. For general purposes, on soil 

 not suited to the Long Red variety, the yellow fleshed Tankards or Globes 

 appear to be the best mangolds. 



Having ascertained the qualities of existing types, the second stage of, 

 the work of improvement begins, and a few roots, which are shown by analysis 

 to contain the largest percentage of food materials, are saved for growing 

 seed. Small plots of both mangolds and swedes were grown in 1904 from . 

 seed so selected, and a second selection was made from these. Seed was 

 grown from these selected roots, and a field crop obtained from this seed in 

 1906, the seed from each root being kept quite separate. Every individual 

 root of this crop has been sampled and analysed, and about 70 selected roots 

 are now being grown on for seed. 



Feeding Value of Mar golds (Cambridge Univ., Dept. of Agric, Guide to 

 Expts., 1907). — In connection with the possibility, referred to above, of 

 breeding improved strains of mangolds, containing less water than those 

 now cultivated, it is considered of importance to compare the information 

 derived from laboratory examination with the results obtained by the stock- 



