ECONOMIC VALUE OF CERTAIN VEGETABLES. 
357 
plants, have subtracted the weight of the pods from the total crop 
weight. 
In estimating the unit of value I have devised this formula, which 
I am quite aware is open to criticism but which I think answers its 
purpose : 
Crop per acre X Energy value of 100 grammes in Calories. 
Time required for crop to reach maturity in weeks 
C x E 
or briefly 
E.g. in Potatos : 
Average crop per acre = 6 tons x Energy value 8375 
= 507-6 -r 
Time to reach maturity^ 20 weeks. 
= 25 Economic Units. 
Potato 
Beet . 
Parsnip 
Carrot 
Green Peas 
Dry Peas 
French Beans 
Broad Beans 
Onion 
Turnip 
Tons per 
acre * 
Weeks 
Time 
Calories 
6 
20 
§3-75 
8 
18 
41-9 
12-5 
26 
32-8 
12-5 
22 
34 
1 
21 
85-1 
i 
307-84 
4 
16 
39'8 
i-3 
18 
90 
7 
8 
10 
I3'5 
8 
10 
Potato . approximately 25 
Carrot 
• 19-3 
Beet Root 
. 18-6 
Parsnip . 
• 15*9 
French Beans . 
• 9*9 
Onion 
. 8-8 
Broad Beans 
• 6-5 
Green Peas (Podded). 
.. 4-2 
Dry Peas 
• 3*9 
Economic Units 
Order 
in List 
(I) 
(2) 
(3) 
(4) 
(5) 
(6) 
(7) 
(8) 
(9) 
Green vegetables have comparatively very little food value, but 
are valuable as ballast and for their contained salts. 
* On a low allotment yield basis. 
